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SEGA Confidential

CONTENTS
System Program User's Manual .......................... 1
SMPC I/F User's Manual ..................................... 7
CD Communication Interface User's Manual ..... 21

System Library

User's Guide

Doc. # ST-162-062094

SEGA Confidential

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ST-162-062094

System Library User's Guide

SEGA Confidential

REFERENCES

In translating/creating this document, certain technical words and/or phrases were interpreted
with the assistance of the technical literature listed below.

KenKyusha New Japanese-English Dictionary
1974 Edition

Nelson's Japanese-English Character Dictionary
2nd revised version

Microsoft Computer Dictionary

Japanese-English Computer Terms Dictionary
Nichigai Associates

4th version

SEGA Confidential

(This page is blank in the original Japanese document.)

SEGA Confidential

Table of Contents

SYSTEM PROGRAM USER'S MANUAL ............................................. 1

1.0

GUIDE .............................................................................................. 1
1.1

Explanation ............................................................................ 1

2.0

REFERENCE .................................................................................... 3
2.1

List of Functions .................................................................... 3

2.2

Function Specifications......................................................... 3

SMPC I/F USER'S MANUAL ................................................................. 7

1.0

GUIDE .............................................................................................. 7
1.1

Objective ................................................................................. 7

1.2

Overview ................................................................................ 7

1.3

System Management System ............................................... 7

1.4

Peripheral Control System ................................................... 8

2.0

REFERENCE .................................................................................. 11
2.1

Data Specification List ........................................................ 11

2.2

Data Specifications .............................................................. 11

2.3

List of Function Specifications .......................................... 15

2.4

Function Specifications....................................................... 16

CD COMMUNICATION INTERFACE USER'S MANUAL ............. 21

1.0

OVERVIEW .................................................................................... 21
1.1

Library Configuration ........................................................ 21

1.2

System Configuration ......................................................... 22

1.3

Functions and Characteristics ........................................... 23

2.0

BASIC FACTS ................................................................................ 24
2.1

Terminology and Symbols ................................................. 24

2.2

Disk Layout .......................................................................... 26

3.0

COMMUNICATION WITH THE CD BLOCK ......................... 27
3.1

Communication Register ................................................... 27

3.2

Communication Method .................................................... 29

3.3

Response ............................................................................... 31

3.4

Data Transfer ........................................................................ 32

iii

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4.0

CD DRIVE ......................................................................... 33
4.1

CD Drive Status Change ....................................... 33

4.2

CD Drive Operation............................................... 37

4.3

Subcodes .................................................................. 39

5.0

CD BLOCK CONFIGURATION .................................... 41
5.1

Data Flow ................................................................ 41

5.2

Stream Process Mechanism................................... 42

5.3

Selector Configuration........................................... 43

5.4

Sector Data Format................................................. 48

5.5

CD Block Initialization .......................................... 49

6.0

CD BLOCK FILE SYSTEM .............................................. 50
6.1

File Management in CD-ROM (ISO9660) ........... 50

6.2

CD Block File System Functions .......................... 51

7.0

DATA SPECIFICATIONS................................................ 55
7.1

Data List................................................................... 55

7.2

Data Detailed .......................................................... 56

8.0

FUNCTION SPECIFICATIONS ..................................... 73
8.1

List of Functions ..................................................... 74

8.2

Function Details...................................................... 76

Index .......................................................................................... 104

SEGA Confidential

Pages 1-20 of this document have been

archived. The revised pages of the

"System Program User's Manual" and

the "SMPC I/F User's Manual" can be

found in ST-162-R1-092994 entitled

"SATURN System Library User's

Guide ver.1.0".

SEGA Confidential

System Library User's Guide

CD Communication Interface User's Manual

1.0 OVERVIEW

This document is a collection of CD block functions and CD communication inter-
face external specifications. Functions of CD blocks are classified in Table 1.1 below.

Table 1.1 Classification of CD Block Functions

CD block functions can be used by a common software interface through the CD
communication interface.

1.1 Library Configuration

The library configuration of CD relationships is shown in Figure 1.1.

Application

Branch Animation Play Library

MPEG Library
(MPG)

Stream System
Library (STM)

File System
Library (GFS)

CD Communication Interface (CDC)

................................................................................

CD Block

SIMM, SCSI

Software

Hardware

Figure 1.1 Library Structure of CD Relationships

Classification

Description

CD Part

Communication format, CD drive related, CD buffer
related

CD block file system related

MPEG Part

MPEG Related

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1.2 System Configuration

The system configuration of CD relationships is shown in Figure 1.2.

Host Program (File system, Application, etc.)

CD Communication Interface

Function Call

Return

(DMA, etc., Data Transfer Module)

Communication

with CD Block

Command

Response

Write data

Fetch data

Hardware Interface

CD Drive

[Command Input/Output Register]

[Data Transfer Register]

CD Block Program (Host Communication Interface, BIOS, etc.)

Communication with CD Drive

B
L

In interfacing with the CD block, the main system is called the host.
Moreover, The CD block is one subsystem.

Figure 1.2 System Structure of CD Relationships

1) Communication with the CD Block

The host and CD block communicate (command/response, data transfer) using
registers on the hardware interface. A command issued from the host to the CD
block is called a CD block command; however, this is normally shortened to
command.

2) CD Drive

The CD block periodically communicates with the CD drive controlling the CD
drive with respect to commands from the host. The CD drive accommodates the
CD-ROM XA standard and multi-session. It is able to switch between the stan-
dard speed as well as double the standard speed. (Standard speed is automati-
cally set when playing CD-DA.)

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System Library User's Guide

1.3 Functions and Characteristics

Numbers "1" to "3" below are functions of the CD communication interface, and "4"
to "7" are CD block functions.

1. CD Block Communication Functions

(a)

Communicates between the host and CD block and is the C Language
interface function set.

(b) Issues commands to the CD block and receives the response.
(c)

Corresponds one to one with the CD block command.

2. Data Transfer Auxiliary Functions

Supports auxiliary functions concerning data transfer such as data transfer
setup and termination as well as data transfer register address acquisition.
Data that is fetched and written in the CD block is sent through the CD block
data transfer register. The transfer itself is not through the CD communication
interface but is through the DMA data transfer module. (Software transfer, SH-2
DMA, and SCU DMA can be done through the CPU.)

3. Register Access Function

Supports functions that access the CD block register.

4. CD Drive Function

Playing music (CD-DA) and sector read (CD-ROM) are handled by a common
command such as CD play. Stop and pause CD play are seek commands.
Resume CD play (cancel pause) is executed by the CD play command.

5. Subcode R ~ W Decode Function

Subcode R ~ W is decoded when playing CD-DA. There is a pack buffer of 23
pack segments for storing decoded pack data.

6. Stream Select Function

CD-ROM XA standard sectors and the stream of every type of device (host,
MPEG, etc.) are processed uniformly.

(a)

There are 200 sectors (about 460 Kbytes) of CD buffer for storing
streams.

(b) There are 24 independent selectors for selecting (separating, storing,

fetching) streams.

7. CD Block File System Function (ISO9660)

Directory information is held in the CD block so that files that conform to the
ISO9660 standard can be easily accessed.

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2.0 BASIC FACTS

2.1 Terminology and Symbols

Definition of T

erms

Terms used are defined in Table 2.1 below.

Table 2.1 Definition of T

erms

Term

Meaning

Sector

Basic units of data handled by a CD block (2352 bytes fixed). The
sector size and configuration follows the CD-ROM format.

Stream

Distinguished by sector headers and subheaders. Flow of logically
continuous data.

CD Buffer

Buffer within the CD block that stores sector data.

CD Buffer Size

Size of CD buffer sector units.

Buffer Partition

Segments CD buffer into multiple logical partitions. (Can be

considered logical elements getting and storing streams.)

Buffer Partition Size

Size of buffer partition sector units.

Sector Location

Sector locations within buffer partition (location of sector units).

Takes the value of 0 to (buffer partition size -1). Sectors of the
buffer partition key-in the sector location and accesses.

Filter

Logical element that separates streams by set conditions.

Selector

Composed from the filter and buffer partition, logical element that
selects streams. The selector enables the construction of a stream
select circuit.

Device

Logical apparatus that causes and absorbs streams such as a CD-
ROM and MPEG. The stream select process is enabled by
connecting a device to the circuit mentioned above.

Connector

Terminal for connecting a filter, buffer partition, or device.

Frame Address (FAD)

Continually adds numbers in frame units with the absolute time

00:00:00 on the CD as 0. Corresponds 1 to 1 with absolute time.

The CD block accesses the frame address as a key and not
absolute time. (both CD-ROM, CD-DA)

Logic Sector No. (LSN)

Continually adds numbers in sector (frame) units with the absolute
time 00:02:00 on the CD as 0. Logic sector number = frame
address - 150 (2 seconds). Used for information within the
directory code (ISO9660).

File Information

Directory record information maintained for accessing files. There

are the file lead FAD, file size, unit size, gap size, file number, and
attributes.

File Identifier

Directly sequence number for identifying files. Takes a value of 0
to (directory record number -1).

0: Own directory, 1: Parent directory.

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System Library User's Guide

List of Symbols and Codes

Symbols and codes used are defined in Table 2.1 below.

Table 2.2 List of Symbols and Codes

Numeric Notation

B is added to the end of a binary number. (Ex: 5 is 101B.)
H is added to the end of a hexadecimal number. (Ex: 255 is FFH.)
A hexadecimal number in a C language program is noted by C language specifica-
tion (0x).

Handling BCD

BCD should not be used in parameters. Numbers recorded as BCD on a CD track
number, for instance, are all converted to binary values.

C Language Identifier

Use identifiers that begin with CD or Cd in the CD communication interface.

Symbol or Code

Meaning

Description

Adr

address

BCD

binary coded decimal

binary decimal number

bn.bufno

buffer no.

buffer partition number

bufnum

buffer numbers

total number of buffer partitions

coding information

channel no.

channel number

Ctrl

control

dst

destination

copy and move destination

fad

frame address

fasnum

fad sector numbers

frame address sector numbers

fid

file identifier

fln, filtno

filter no.

filter number

file no.

file number

LSB

least significant bit

MSB

most significant bit

ply

play parameter

play parameters

pos

position parameter

position parameters

submode

sct

sector

ses

session information

sesno

session no.

session number

snum

sector numbers

(when

specifying

sector range of partition)

sp. spos

sector position

(when

specifying

sector range of partition)

src

source

copy / move source

stat

CD status information

subh

subheader condition

subheader condition for filter

TNO

track no.

track number (music number)

toc

TOC information

txwnum

transfer word numbers

(data transfer size in word units)

X, idx

index

index number

word

units 2 bytes (16 bits) in length

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2.2 Disk Layout

Track Layout

Figure 2.1 shows the relationship of the track configuration with the access key that
indicates the position on the disk.

Information Area

Program Area

Q Code

Control

TON

Index

Time

Absolute Time

ATime

Header

(minute, second, frame)

Logic Sector

(LSN)

Frame Address

(FAD)

Lead in

Area

Data

Audio

Lead Out

Area

Audio

2 sec.

01~

TOC Information

FAD=0 Track start FAD

Track start FAD

Figure 2.1 Relationship of T

rack Configuration and

Access Key

Multi Session Layout

TNO

Absolute Time

ATime

Header

(minute, second, frame

Logic Sector Number

(LSN)

Frame Address

(FAD)

TOC Information

Track start FAD

Session start FAD

Track start FAD

Session start FAD

Track start FAD

Session start FAD . . ..Index is 00

Session Information

2 sec.

Session 3

Session 2

Session 1

03 AA 00

AA 00

Figure 2.2 Multi Session Layout

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System Library User's Guide

3.0

COMMUNICATION WITH THE CD BLOCK

3.1 Communication Register

Table 3.1 shows the CD block and communication registers and corresponding
access functions.

Table 3.1 Communication Registers

* All access widths are 16 bits (1 word)

See below for more information about the communication register.

In the figure, a reserve bit is shown by " - " The reserve bit must be specified with a
0. The bit configuration is 15 for the most significant bit and 0 for the least signifi-
cant bit.

Data Transfer Register (DATATRNS)

When transferring data, this register inputs and outputs data between the host and
CD block. The inner part of the register is FIFO.

Register Name

R/W

Description

Access Function

DATATRNS

R/W

Data Transfer Register

CDC_GetDataPtr

HIRQREQ

R/W

Interrupt Factor Register

CDC_GetHirqReq,

CDC_ClrHirqReq

HIRQMSK

R/W

Interrupt Mask Register

CDC_GetHirqMsk,

CDC_SetHirqMsk

MPEGRGB

MPEG Register (RGB data)

CDC_GetMpegPtr

R/W

DATATRNS

R/W

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Interrupt Factor Register (HIRQREQ)

This is the interrupt factor register from the CD block to the host.

CMOK (bit 0) : Issueable command 1 = command can be issued (response set complete)
DRDY (bit 1) : Data transfer ready 1 = data transfer setup is complete.
CSCT (bit 2)

: 1 sector stored

1 = 1 CD-ROM sector is stored or discarded in partition

BFUL (bit 3)

: CD buffer full

1 = CD buffer is full

PEND (bit 4) : CD play end

1 = CD play has ended (current FAD is outside play range)

DCHG (bit 5) : Disk exchange

1 = Disk has been exchanged (tray has been opened)

ESEL (bit 6)

: Selector set end

1 = soft reset, stop execution of selector set

EHST (bit 7)

: Host I/O end

1 = stop execution of host input/output

ECPY (bit 8)

: Copy end

1 = stop execution of copy and move between buffer

partition
EFLS (bit 9)

: File system end

1 = stop execution of CD block file system

SCDQ (bit10) : Subcode Q

1 = subcode Q renewal complete

(CD drive communication timing)

bit 11 ~ bit 13

MPEG related interrupt factor (see MPEG part for the meaning of each bit)

(a) Bit write can only be done at 0 (clear), not at 1.
(b) The IRQ output to the host is OR output of all factors.

Clears corresponding factor bits during interrupt process.

Reports the end of execution of commands belonging to each flag.

Interrupt Mask Register (HIRQMSK)

This register is for masking interrupt from the CD block to the host.

(a) Bit content is the same as the HIRQREQ register.

(1 = interrupt enable, 0 = same mask)

(b) This occurs if interrupt is masked (corresponding bit = 0) when interrupt occurs.

· not reflected in IRQ output.
· reflected in the HIRQREQ register. (Polling process possible)

R/W

HIRQREQ

R/W

SCDQ

EFLS

ECPY

EHST

ESEL

DCHG

PEND

BFUL

CSCT

DRDY

CMOK

R/W

HIRQMSK

R/W

SCDQ

EFLS

ECPY

EHST

ESEL

DCHG

PEND

BFUL

CSCT

DRDY

CMOK

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System Library User's Guide

MPEG Register (MPEGRGB)

This register is for transferring in the RGB format MPEG frame buffer image data
that is in the RGB format to the host.

bit 0 ~ bit 15 : RGB data (See MPEG part for the meaning of each bit.)

3.2 Communication Method

Communication Time

All interrupts are prohibited during the response time of command/response. Re-
sponse time may be delayed when commands are continuously issued.

Communication Error

A communication time out error occurs when the CD block does not respond (com-
mand is not returned) within the prescribed time after a command is issued.

Command Issue Provisions

Command issue must obey the following provisions.
(a) A maximum of 30 commands can be issued within 6.7 ms.
(b) A maximum of 60 commands can be issued within 16.7 ms.
(c) When acquiring a subcode, a maximum of 34 commands can be issued within

13.3 ms. (subcode R~W is 16 commands + subcode Q is 1 command)

(d) Commands belonging to the same command end flag wait for execution to

end and are issued.

<Program Guide>
The polling process by continuously issuing commands is prohibited.
Regular response and the interrupt factor register are used in the polling of condi-
tion changes. Use of timing through the CSCT and SCDQ flags, and VSYNC issues
commands.

R/W

MPEGRGB

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Command End Flag

The end of execution of each command listed below is posted.

Table 3.2 Commands belonging to the Command End Flag

(a)

The ESEL flag also posts the end of soft reset execution.

(b) The EFLS flag is 1 when opening the tray and when stopping file access.

Command End Flag Process in CD Communication Interface

When commands belonging to the command end flag are issued, the CD communi-
cation interface function does the following.
(a)

Checks the command end flag, and if 0, does not issue a command.

(b) If 1, the command end flag is cleared to 0 and a command is issued.

The command end flag is processed when the following commands are issued.
· Soft reset

Clears ESEL flag to 0 (no check)

· Gets actual data size

Checks ESEL flag (not cleared to 0)

· Gets frame address find results

Checks ESEL flag (not cleared to 0)

· Stop file access

Clears EFLS flag to 0 (no check)

F l a g

Command

ESEL

· Set CD device connection source

Set filter frame address range

· Set filter subheader conditions

· Set filter mode

· Set filter connection destination

· Reset selector

· Calculate actual data size

· Execute frame address find

· Set sector length

EHST

· Fetch sector data

· Cancel sector data

· Cancel sector data fetch

· Write sector data

ECPY

· Copy sector data

· Move sector data

EFLS

· Move directory

· Save file information

· Read file

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System Library User's Guide

3.3 Response

Response Contents

Response is composed of a 1 byte status and 7 byte report. The status are common
but the report depends on the command. This most basic of reports is the CD report.

Status

The following information returns to status.

· REJECT (improper command)

Command itself is invalid due to
mistake in command format.

· WAIT (hold execute)

Cannot be executed under current
conditions, therefore command can
not be received.

· Data transfer request

Shows that data transfer is necessary.

· Periodic response

Shows whether a periodic response or
response to a command.

· CD drive condition

Shows the logical condition of the
CD drive seen from the host.

(a) Response during REJECT is invalid.
(b) Status during WAIT and CD report are effective but other reports are ineffective.

Periodic Response

Periodic response is a response that returns with the communication timing of the
CD block with the CD drive. The host can obtain information (status and CD report)
without issuing a command. It is periodically updated by the communication cycle
with the CD drive. (Same as the SCDQ flag update timing.)

Periodic response update cycle

At standard playing speed

At double playing speed
When not playing

: 13.3 ms
: 6.7 ms
: 16.7 ms

Update is not done during command/response. After response is read by com-
mand, it is updated according to the next CD drive communication timing.

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3.4 Data Transfer

Data Transfer Procedure

When using commands to transfer data, the host must do the data transfer process
after the command/response. This procedure is listed below.

(a) The command needed for transferring data is executed (data fetch/write).
(b) Data transfer setup wait is executed. (Wait until the DRDY flag is 1).
(c) Data is input and output through the data transfer register (DATATRNS).

Get Data transfer register pointer is executed when getting the address.

(d) Data transfer end is executed when the necessary data is transferred.

Data Transfer End

When there is a data transfer request by status, end data transfer must be executed
even when no data is actually transferred. This is not necessary for REJECT and
WAIT. When an error occurs with the data transfer setup wait, the application does
not need to execute data transfer end. Execution is automatically done within the
setup wait function.

Data Transfer Errors

Table 3.3 shows errors that occur while waiting for the setup of data transfer.

Table 3.3 Data Transfer Errors

Data Transfer Error

Description

Data transfer time out

CD block does not complete data transfer

setup within the prescribed time.

(DRDY flag remains at 0 and does not change
to 1)

Write sectors cannot be secured

Empty sectors could not be reserved by writing
sector data.

(With the DRDY flag at 0 the EHST flag is 1.)

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System Library User's Guide

4.0

CD DRIVE

4.1 CD Drive Status Change

CD Drive Status

Table 4.1 CD Drive Status

Types of Drive Commands

Table 4.2 shows the types of commands (drive commands) that change the CD drive
status.

Table 4.2 Types of Drive Commands

(a) When doing a soft reset, CD block initialization does not operate as a drive

command.

(b) Drive commands other than tray open can be done concurrently with the tray

close command.

Issuing Drive Commands

(a) Drive command response must return the <BUSY> status as long as there is

no REJECT.

(b) As a rule, command issued afterwards are issued by priority.

Status

Explanation

<BUSY>

Status change in progress

<PAUSE>

Temporarily stopped

Drive stop status

<PLAY>

CD play in progress

<SEEK>

Seeking

<SCAN>

Scanning

<OPEN>

Tray is open

There is no disc

<RETRY>

Read retry in progress

<ERROR>

Read data error occurred

<FATAL>

Fatal error occurred (hard reset required)

Drive Commands

Corresponding Functions

Initialize CD block

CDC_CdInit

Open tray

CDC_CdOpen

Play

CDC_CdPlay

Seek

CDC_CdSeek

Pause

CDC_CdSeekd

Stop

CDC_CdSeek

Scan

CDC_CdScan

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4.1.1

Illustrations of CD Drive Status Change

1) Status Change Illustration of a Normal System.

Figure 4.1 illustrates the status change of a CD drive in a normal system.

OPEN

NODISC

STANDBY

PAUSE

SEEK

SCAN

PLAY

START

Scan command

Seek Command

Play Command

Automatic

Standby Time Elapsed

Stop Command

CD Block Initialize Command
Pause Command

All Drive Command

Opened

Tray is closed

Disc

Yes

TOC Read

Tray Open Command
Manual Open

Hard Reset

Tray Close Command
Manual Close

Figure 4.1 Illustration of CD Drive Status Change (Normal System)

(a) <PAUSE> occurs two seconds after TOC read at frame 0 (FAD=150=96H).
(b) The <BUSY> status indicates that a status change is in progress (on arrow line).
(c) The tray close command specifies drive commands other than tray open. The

status corresponding to every command changes after the tray is closed.

Example:

Play command in the <OPEN> status changes to the <PLAY> status after the
tray is closed.

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System Library User's Guide

2) Status Change Illustration of an Error System.

Figure 4.2 illustrates the status change of a CD drive in an error system.
Statuses are explained in Table 4.3.

OPEN

NODISC

STANDBY

PAUSE

SEEK

SCAN

START

Automatic

Standby Time Elapsed

Stop Command

CD Block Initialize Command
Pause Command

All Drive Command

Opened

Tray is closed

Disc

Yes

TOC Read

Tray Open Command
Manual Open

Hard Reset

Tray Close Command
Manual Close

RETRY

ERROR

FATAL

PLAY

Each Command

Fatal Error

Retry

Retry Succeeded

Read Data Error

Each Command

Retry Failed

Figure 4.2 Illustration of CD Drive Status Change (Error System)

Table 4.3 Error Relationship Status

Internal conditions indicate equal conditions as CD block internal operations.

Status

Explanation

Internal Status

<RETRY>

<PLAY> if retry succeeds and <ERROR> if retry fails.

<SEEK>

<ERROR>

Status does not change until the next drive command
is issued.

<PAUSE>

<FATAL>

Stops the disc motor rotation. Hard reset is required.

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4.1.2

Table of CD Drive Status Changes

Table 4.4 lists status changes of the CD drive. For example, if the pause command is
issued during <PLAY>, <PAUSE> will be displayed.

Table 4.4 Table of CD Drive Status Changes

indicates no change.

1) Commands issued in the <BUSY> status.

Commands issued in the <BUSY> status can be received but there is noguarantee
of immediate execution. For example, While the tray is being opened or closed, a
command is not executed until that operation is over. (However, the tray open
command is executed immediately.)

2) Tray Open/Close.

(a) As a rule, the tray open command is executed immediately in any mode.
(b) The tray open/close command when not using the automatic open/close

format is <BUSY> until executed manually.

status after the tray close process.

(d) When the tray is closed, <NODISC> occurs if TOC read cannot be done.

(Even if there is a disc).

3) Status Routings.

(a) Everything goes though the <BUSY> status when done by command.
(b) In some cases the routing is by way of <SEEK> when changing to the

<PLAY> and <SCAN> statuses.

4) In the case of Multi Sessions.

(a) Reads the final session of TOC.
(b) After TOC is read, the <PAUSE> status is at the 0 frame, 2 seconds

from the start position of the final session.

Operation

Commands

& Status

Automatic

Initialize

Tray Open

Play

Seek

Pause

Stop

Scan

<BUSY>

changes

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<PAUSE>

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<PLAY>

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<SEEK>

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<OPEN>

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<OPEN>

<OPEN>

<RETRY>

changes

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<ERROR>

<PAUSE>

<OPEN>

<PLAY>

<SEEK>

<PAUSE>

<SCAN>

<FATAL>

undefined

undefine

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System Library User's Guide

4.2 CD Drive Operation

<PLAY> Status Frame Address

The frame address (currently FAD) posted while a CD is playing indicates the sector
during the read process. The current FAD sector is not stored in the CD buffer and
cannot be retrieved. The host can access up to one sector before the current FAD. (In
the case of a CD-ROM).

FAD-1

Current FAD

Store in CD buffer During Read process

(retrievable)

(not retrievable)

Figure 4.3 Sectors that the current FAD indicates

When play has ended, FAD = play end position + 1. (The read out area is indicated
when the play end position concludes at the end of the disc.)

Change from <PLA

Y> Status and Sector Storage

When changing from <PLAY> to a different status, whether the sector during the
read process can be store is undefined. If changing to any status other than <BUSY>
the sector that should be stored is defined. When the pause command is issued in
the <PLAY> status and the status changes from <PLAY> to <PAUSE>, the storage
sector + 1 FAD is posted the same as with 1).

Play Range and Frame

Address

By changing play end, seek, and the play range, <PAUSE> occurs when FAD is
outside the play range and the PEND flag of the interrupt factor register becomes 1.
When FAD is outside the play range, the <PAUSE> status cannot be canceled (restart
play). Canceling <PAUSE> when FAD is within the play range changes the status to
<PLAY>.

CD Play Repeat Process

Both the repeat post frequency (0H~EH) and maximum indication frequency
(0H~FH) are shown by 4 bits. After the frame of the play end position is played
(FAD = play end position + 1), the following process is performed.

(a)

If the repeat frequency is less than maximum repeat frequency, CD play will be
repeated (return to the start position and continue playing). If the repeat
frequency is <EH(14 times)> at that time, the repeat frequency is increased by 1.

(b) If the repeat frequency is greater than or equal to the maximum repeat

frequency, CD play will not repeat (play end position + 1 and pause).

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If the play range or maximum repeat frequency changes, the repeat frequency clears
to 0. Neither the repeat frequency nor play range rely on the tray open/close or the
seek operation while play is in progress.

Seek the Home Position (Stop)

The following operations are done by seeking the home position.
(a)

The disc motor rotation stops and pickup is moved to the standby position
inside the circumference.

(b) The CD drive status changes to <STANDBY> and report is an invalid value

(FFH line).

(c)

When the status changes from <STANDBY> in the home position to <PAUSE>,
seek moves to the start of the disc.

(d) The play range, maximum repeat frequency, and repeat notification frequency

which have been saved cannot be changed.

Pickup Position in the <ST

ANDBY> status

· Moving from the <PAUSE> status:

Current position (report also remains
unchanged).

· When seeking the home position:

Standby position inside the circumference
(report is an invalid value).

CD Read in a Full CD Buffer

If the CD buffer becomes full, a <PAUSE> will occur and the BFUL flag of the inter-
rupt factor register becomes 1. When there is space in the CD buffer, play automati-
cally starts where it left off.

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System Library User's Guide

4.3 Subcodes

Subcode Update and SCDQ Flag

The subcode Q is updated for each frame (one sector). The SCDQ flag becomes one
every time subcode Q is updated (same as update timing of periodic response).
Subcode R~W can update four packs (one packet) with one frame and be stored in
the pack buffer. There is a 23 pack (short of six packets) segment in the CD block.

<Standard Speed when playing CD-DA>

13.3 ms

Subcode Q Update

01 23

89 A B

45 67

C DE F

5 6 7 8

1 2 3 4

SCDQ Flag

Pack Data Aquisition

(Subcode R

Pack Data Update

(Subcode R

W Decode Completion)

The SCDQ flag clears the host to 0. The CD block is only 1. Subcode R~W begins the
decode process when data fetch starts and if 8 packs have been collected.

Figure 4.4 Subcode Update and SCDQ Flag T

iming

Subcode Get Timing

The host issues the Get command by a timing with the SCDQ flag at 1 and gets
subcode Q and R~W data. (Polling is prevented by continuously issuing commands.)

Getting Subcode Q

The Get command can be executed any time regardless of the CD drive status. But
when in the <OPEN> status, ineffective values may return depending on the CD
drive status.

Getting Subcode R~W

Pack data reissues the Get command and gets data until the pack buffer is empty.
However, exceeding 16 packs within the time of one frame (13.3 ms) is not allowed.
WAIT is returned if the pack buffer is empty and pack data disappears.

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Subcode R~W Decode

(a)

Decode start and end
Decode On/Off are set by the initialize command of the CD block.
To start decoding, set decode to ON then execute CD-DA play.

(b) Decode Start Timing

Start decode during <PLAY>.
Data actually begins to be retrieved two frames before <PLAY>.

(c)

Pack Buffer Clear Timing
Clear is done when decode begins.
The pack buffer content is saved even when doing seek and pause.

(d) Decode Conditions

Decode is done only when playing CD-DA.
Decode is not done in other cases (while scanning or playing the CD- ROM
area)

Subcode R~W Error

(a)

Over Run Error
If a pack is not fetched in time, the pack buffer is overwritten and an over run
error occurs. After data transfer has ended, the get pointer advances to the
extent that the pack is without an overrun error. The host must finish transfer-
ring data within the decode time of 1 pack (3.2 ms).

(b) Pack Data Error

Pack data checks CRC and corrects the data if an error is detected. A pack data
error occurs if the data cannot be corrected.

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5.0

CD BLOCK CONFIGURATION

The characteristics and logical configuration of the CD block as seen from the host is
shown below.

Data Format

The basic unit of the stream handled by the CD buffer is a fixed size (2352 bytes)
sector no matter what the device is.

Stream Select Circuit

The functions that separate and store streams are attained by a filter and buffer
partition design. These functions are considered to be logical elements (selector).
The circuit that selects the necessary streams is constructed by combining selectors.

Device

The CD and MPEG are considered to be logical devices that produce and absorb
streams. The flow of a stream is controlled by connecting a device to the stream
select circuit.

5.1 Data Flow

Figure 5.1 shows the entire data flow for a CD block.

Decode

RGB888

RGB555

Display

Get

Put

Write

Read

Write

CD Read

[CD Play]

Copy, Move

CD Block

Host

CD-ROM

MPEG Buffer

MPEG Decoder

MPEG Frame

Buffer

CD Buffer
(Buffer
Partition)

Host

MPEG Register

(RGB)

Data Transfer

VDP2

Figure 5.1 CD Block Entire Data Flow

System Library User's Guide

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5.2 Stream Process Mechanism

Figure 5.2 shows the overall configuration of the CD block from the viewpoint of
stream flow.
.

There are 24 selectors numbered 0 to 23.

Figure 5.2 CD Block Overall Configuration

[What each part does]
(a) Device:

Produces and absorbs streams (stream inflow and outflow device.)

(b) Selector: Composed of a filter and buffer partition, used for selecting streams.
(c) Filter:

Separates streams by set conditions (conforms to Yes/No conditions.)

(d) Buffer Partition:

Stores streams, releases or cancels data through outside
requests.

There are connectors for connecting every device to a selector. The device and selector
input/output connectors are 1 to 1. Connections can be made between selectors as well.

Connections flow regularly in streams by connecting connectors that don't pass
through partitions and stop when entering a partition. Sectors that are output from
an output connector that is not connected will be canceled.

Devices must be connected through a selector. A device output connector can only
connect to a filter input connector, and a device input connector can only connect to a
partition output connector.

Stream outflow device

Stream inflow device

Device output connector

Device input connector

Filter input connector

False output connector

Partition output connector

Copy / Move

Filter

Buffer partition

CD-ROM

Host

MPEG buffer

MPEG frame buffer

Host

MPEG decoder (A)

MPEG decoder (V)

MPEG buffer

MPEG frame buffer

Selector

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5.3 Selector Configuration

The selector process function does not rely on the parts connection destination or
device. It separates and stores the input stream and only outputs by request. Figure
5.3 shows the selector configuration.

Filter input connector

True output

connector

Partition input

connector

Partition output

connector

Buffer partition

Filter

False output

connector

Figure 5.3 Selector Configuration (Initial condition)

In the initial condition of the selector, the filter and partition with the same number
are connected through the true output connector and partition input connector.
Other connectors are not connected.

5.3.1

Filter

Conditions (FAD range, subheader) of the sector that should pass are set in the filter.
Sectors that match with the conditions are output to the true output connector and
stored in buffer partition of the connection destination. All other sectors are output
to false output connectors.

False output connectors can be connected to other filter input connectors and
achieve in secession similar selection processes. Sectors output from unconnected
output connectors will be deleted.

Decide conditions Store

Yes

Stream

Clear

Figure 5.4 Type of Stream Select Process

System Library User's Guide

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5.3.2

Buffer Partition

1) Buffer Partition Configuration

The CD buffer is divided into several buffer partitions. Figure 5.5 shows the
configuration of a buffer partition.

No -1

-1

Sector postion

Last partition

First partition

Buffer partition size (sector units) Np

2 3

Buffer partition number

Np: buffer partition size, P: buffer partition number,

CD buffer size

p=20

Contents of each partition are not fixed; data can be stored as long as there is space in the
whole CD buffer.

Figure 5.5 Buffer Partition Configuration

2) Storing Sectors to the Buffer Partition

Sectors entered in partitions are stored in the last partition. The last sector
position of the partition is equal to the buffer partition size minus 1.

3) Discharging and Canceling Sectors from the Buffer Partition

Two ways to discharge sectors from partitions are to keep the sectors at the
partition discharge source or clear the sectors (clear only can also be selected.)
For example, get to the host corresponds to "Get" and "Get and Clear."
Flowing in and out between selectors corresponds to "Copy" and "Move."

4) CD 1 Sector Interrupt and Store Destination

One sector interrupt in CD read occurs in each sector at the time the sector is
stored in the partition. The CD block stores the partition number of the store
destination. The store destination partition number of the sector read last can
be retrieved from the host.

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5.3.3

Connectors

1) Connection from Buffer Partition to Filter (Sector Data Copy/Move)

The partition output connector is connected to the filter input connector and the
flow of sector data allows sector data to be copied and moved. The connection
and flow I/O process are executed by executing one command.

Because only the selected number of sectors
flow, loop does no continue indefinitely.

(a) Copy/Move for different selector (b) Copy/Move for self

Figure 5.6 Copy/Move Sector Data

2) Selector Connections by OR Condition (multi to one connection)

True output connectors of several filters can be connected to the same partition
input connector. This enables a sector to be stored in whichever of several
conditions it coincides with.
(OR condition: logical add).

A or B

Figure 5.7 Selector Connection by OR Conditions

System Library User's Guide

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3) Types of Connectors and Connection Destination

Table 5.1 Types of Connectors and Connection Destination

O :

connectable (1 to 1),

only 1 output connector can connect
to 1 input connector.

connectable (multi to 1),

several output connectors can
connect to the same input connector.
(OR condition)

X :

not connectable

Whether to do a simple process of connecting (disconnecting) by one command
or a complex process collecting connections and flow in/out processes depends
on each device. The CD-ROM and MPEG decoder are single processes. Others
(host, copy/move, etc.) are complex processes.

Output/Input

Filter Input

Partition Input

Device Input

Device Output

True Output

False Output

Partition Output

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5.3.4

Selector Precautions

1) Error in the Stream Process

Except with the CD device, error in the stream process occurs in the following
cases.

Connection separates during operation.

CD buffer becomes full while reading or writing to the buffer partition.

2) Selector Set Effective Timing

FAD with selector settings made effective while a CD is playing is within
one FAD from response of the selector set command. The host considers the
margin and issues the set command before 10 or more sectors of the target FAD.
When the selector setting has ended, the ESEL flag of theinterrupt factor register
becomes 1.

3) Sector Data when Changing Connections

When the CD is being read, data is not omitted even if the connection changes
during the sector data sequence. In short, the flow of data is guaranteed when
temporarily interrupted while switching connections.

4) General Access to the Buffer Partition (general command specifying sector

position and sector range)
Returns to WAIT when the specified sector range doesn't exist like the data
number within the partition is exceeded. Always returns to WAIT when the
data number within the partition is 0.

5) Clear Discharge from Buffer Partition

When a sector is cleared and discharged from a partition, all data of the selected
sector range is cleared (get and clear or move sector data) even if the process
stops because of an error etc.

System Library User's Guide

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5.4

Sector Data Format

1) Basic Format

Sector data format basically conforms to the CD-ROM XA sector format.

2) Handling Sub header and User Data (2048 bytes)

(a) Sub header except for Mode 2 (mode part within header is 02H) is handled

as 0.

(b) There is user data immediately after the header only for Mode 1 (mode part

within header is 01H). Otherwise, user data is considered to exist in the
same position as mode 2 form 1.

the same as mode 2 form 1. The first 24 bytes is 0, and data after the user
data is undefined.

User Data

EDC/ECC, etc.

User Data

EDC/ECC

EDC,
etc.

Header

Sub
header

Sector
synch

2048

288 bytes

2048

280 bytes

2324

4 bytes

2340 bytes

2336 bytes

2352 bytes

CD-ROM

Mode 1

CD-ROM XA

Mode 2

Form 1

CD-ROM XA

Mode 2

Form 2

FN: File Number
CN: Channel Number

SM: Sub Mode
CI: Coding Information

MIN SEC

FRAME MODE

4 bytes repeat

1 byte

Figure 5.8 CD-ROM XA Sector Format

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5.5 CD Block Initialization

TOC/Session Information

Initialized when the tray is opened, and information is in a non-input condition.
Reads TOC when tray is closed (unrelated to the reset of software.)

File Information

Initialized if tray is opened or software is reset, and information is in a non-input
condition. The host explicitly commands the reading of file information.

Host Information

Initialized if software is reset (unrelated to opening the tray.)

[Host Information] . . . . . . mostly host set information and buffer data

Initialization information (CD block initialization parameters)

Play information (play range, maximum number of repeats, current repeat
notification number)

Selector information (filter, buffer partition, etc., host setting for selector)

Data within buffer, buffer partition size, space size

Actual data size retained, setting of sector length

Data transfer control register (initializing ends transfer of data)

MPEG related information

If the CD block is initialized without resetting the software, information in the TOC/
Session and Host is not initialized.

System Library User's Guide

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6.0 CD BLOCK FILE SYSTEM

6.1 File Management in CD-ROM (ISO9660)

The CD block file system supports a logic format that conforms to ISO9660.

Root directory

Sub directory

Root directory

Self

Parent=Self

Sub directory

Parent

Sub directory

Parent

Directory code

Directory block
(Directory file)

File

Pass table

Volume Identifier

Pass table code

Directory number

Pass table size
Pass table address
Root directory code
of Root directory

Directory block address
Parent directory number
Directory name

File lead sector address
File size
File name
System information for mode 2
(file number, form information)

Volume identifier :

Arranged from CD 00:02:16 (FAD = 166 = A6H)

Pass table :

A collection of pass table records. Pass table size and
address are recorded in the volume identifier.

Pass table record :

Corresponds to one directory (root, sub)
Record position is the directory number (1 ~ n)
Directory information is listed in the directory book.

Directory block :

A collection of directory records. A directory block is
considered to be one file. (directory file)

Directory record :

Corresponds to one file (includes directory).

Figure 6.1 File Management Data Configuration in CD-ROM (ISO9660)

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6.2 CD Block File System Functions

The CD block file system (referred to "file system" hereafter) has the following
functions.

1) Moves directories and holds file information

Moves to the specified directory and holds in the CD block file information
within that directory.

2) Gets file information

Transfers held file information in response to a request from the host.

3) Reads files

Reads file sector data originating from held file information to the CD buffer.
The host is able to extract read sector data by data transfer.

4) Stop Accessing Files

CD play stops by moving a directory, holding file information, and reading a
file. If file access is stopped, the CD block pauses the CD drive.

Root directory

Parent=Self

File 1

Self

Parent

Self

Parent

File Information Table

Move directory

(Hold file information in directory move destination)

255

File i

File i + 1

File j

File i+n-1

. . .

File i

File i + 1

File j

File i+n-1

. . .

File j

Reading file

Buffer partition

Holds file
information

Directory record sequence number

File identifier (fid)

1+i

i+n -1

. . . . File information of the current directory self

fid = j

Held file information number (n)

Held identifier of first file (i)

Directory block (for directory record)

Figure 6.2 CD Block File System Configuration

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6.2.1

File Information Holder Method

The CD block provides 256 file information tables that hold file information for
accessing. The first two parts in this table always holds current directory (self) and
parent directory information. Up to 254 parts of ordinary file information can be
held. (The number cannot be designated.)

1) Directory Move

If a directory is moved, the directory record is read, and file information is
extracted and held in a table. The range that is held is from the start of the
directory block.

2) Holding File Information (specifying the hold range)

Specifies a file identifier and can hold file information from any position
within the current directory. In this case also, self and parent information is
held in the first two parts of the table.

6.2.2

File Access Procedure

1) Moving to the Root Directory

In using the file system, first move to the root directory and create a file informa-
tion table. This is the same when file information is cleared when starting up or
changing disks. Neither a table can be created nor the file system used if the
disk is not in the ISO9660 format. (REJECT occurs if getting the holding file
information range.)

2) Holding File Information

The file system can access only files inside the file information table. When
accessing a file, the file information must be held beforehand. When moving
directories, the target directory must be held.

3) Reading Files

File identifier and offset (sector units) are selected and the file read. The read
destination selector is selected by the filter number.

4) Getting Sector Data

Files read to the buffer partition transfer and fetch data by fetching sector data.
Data can be fetched while reading ,and there is no waiting for read to end.
Pause occurs if the CD buffer becomes full while reading files. If a space can be
created, pause is canceled and the remaining files read.

5) Ending File Read

When file read has ended, the EFLS flag of the interrupt factor register becomes
"1". Executing the file access stop command stops file read. (Accessing a file is
done in the same by moving a directory and holding file information.)

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6.2.3

File System Precautions

1) Work Selector Designation

When reading file information from the CD-ROM, the CD block requires a work
selector. One selector can be designated to move a directory and hold file
information. At least one empty sector is required at this time. The selector
used is canceled after the process ends.

2) Selector Settings

When accessing to a file, the file system does the following settings for the
selector.

(a) Connection conditions of indicated filter

filter input connector

: connects with a CD device.

true output connector

: connects with buffer partition with the same

number.

false output connector : cuts off other selectors.

(b) Filter conditions

Table 6.1 Set Filter Condition

The buffer partition sectors are cleared before files are accessed.

3) CD Play Range and Drive Command

When accessing a file, the play range becomes the default value (disk first to
last). The drive command (CD play, pause, etc.) is executed unchanged even
with the file system in operation. Be aware that operation of the file system
can be obstructed. Auto pause/cancel-pause operate normally when the buffer
is full.

4) File Access End and Stop

When file access ends or is stopped, the EFLS flag becomes 1. File access also
stops if the tray is open. (But before the <OPEN> status, EFLS = 1.) While
directory move and file information hold are being executed, the file information
table is destroyed if file access stops.

Action

Filter Condition

Move Directory

Sets filter frame address range (FAD range)

Hold File Information

Makes effective the frame address range of the filter mode

Read Files

Sets filter frame address range.

Sets the file number of the filter subheader conditions

Makes effective the filter mode FAD range and file number selection

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5) Multi Session

In multi session cases, the file system refers to the volume descriptor of the last
session.

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System Library User's Guide

7.0

DATA SPECIFICATIONS

This chapter lists the constants, data types, access macros, etc. used by the CD com-
munication interface.

· Format

In the figures, the reserved regions are shown by the "" mark. A 0 must be
specified in the reserve regions.

7.1

Data List

Table 7.1 is the CD communication interface data list.

Table 7.1

Data List

Data

Name

Number

Basic data

1.0

Constants

2.0

TOC information & Session information

3.0

Status and Report

4.0

Subcode information

5.0

Data Types

6.0

CD communication function return code

CdcRet

6.1

CD status information

CdcStat

6.2

Hardware information

CdcHw

6.3

CD position parameters

CdcPos

6.4

CD play parameters

CdcPly

6.5

Sub header conditions

CdcSubh

6.6

Sector information

CdcSct

6.7

File information

CdcFile

6.8

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7.2

Data Detailed

7.2.1

Basic Data

Title

Data

Data Name

Data Specification

Basic Data

1.0

1) Basic Data Types

Type Name

Description

Uint 8

1 byte integer without code

Sint 8

1 byte integer with code

Uint 16

2 byte integer without code

Sint 16

2 byte integer with code

Uint 32

4 byte integer without code

Sint 32

4 byte integer with code

Boo 1

logical type 4 byte integer (assumes logic constant as
value)

2) Logic Constants

Used as a logic (Boo 1) value.

Constant Name

V a l u e

Description

FALSE

Indicates that logic value is false

TRUE

Indicates that logic value is true

OFF

Indicates switch is off (false)

Indicates switch is on (true)

3) Additional

Constant Name

V a l u e

Description

NULL

((void *)0)

NULL pointer

Used as a logic (Bool) value.

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7.2.2

Constants

1) Bit Names of interrupt factor register relationship

(HIRQREQ, HIRQMSK).

2) Special designation of buffer partition sector range

(sector location and sector number).

Effective with functions that correspond to the buffer partitions below.

CDC_CalActSiz,

CDC_ExeFadSearch,

CDC_GetSctInfo,

CDC_GetSctData,

CDC_DelSctData,

CDC_GetdelSctData,

CDC_CopySctData,

CDC_MoveSctData

N-1

Buffer Partitions

CDC_SNUM_END

CDC_SPOS_END

Designated Sector Location SP

Stream

Filter

3) Other

Title

Data

Data Name

Data Specification

Constants

2.0

Constant Name

Description

CDC_HIRQ_CMOK

Enable commands to be issued

CDC_HIRQ_DRDY

Prepare data transfer

CDC_HIRQ_CSCT

Store 1 sector

CDC_HIRQ_BFUL

CD buffer is full

CDC_HIRQ_PEND

CD play end

CDC_HIRQ_DCHG

Disk change

CDC_HIRQ_ESEL

End Selector set

CDC_HIRQ_EHST

End host input/output

CDC_HIRQ_ECPY

End copy

CDC_HIRQ_EFLS

End file system

CDC_HIRQ_SCDQ

Subcode Q

Constant Name

Description

CDC_SPOS_END

Indicates sector location of last partition
Same as (sector no. in partition - 1) designated

CDC_SNUM_END

Sector number from designated sector location SP

to last partition.
Same as designated (sector no. in partition - SP)

Constant Name

Description

CDC_NUL_SEL

Special value of selector no. (filter number, buffer
partition number)

CDC_NUL_FID

Special value of file identifier

System Library User's Guide

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7.2.3

TOC and Session Information

1) TOC Information

Track 1 Information

100

101

4 Bytes

Track 3 Information

Track 2 Information

Track n + 1 Information

Track 99 Information

First Track Information (A0)

Last Track Information (A1)

Read Out Information (A2)

Location
information
of every track
(99 tracks)

4 byte unit offsets

Track start frame address

byte 0

Ctrl Adr

Tracks not existing on TOC is FFFFFFFFH

Read out start frame address

Ctrl Adr

Indicates final session value for multi sessions

Ctrl Adr

First track

number

Last track

number

PSEC

PFRAME

PSEC

PFRAME

POINT=A0 Value

POINT=A1 Value

byte

First/Last track numbers are PMIN binary values

2) Session Information

byte

Total Session Information

Session 1 Information

Session 2 Information

Session 98 Information

Session 99 Information

Session n Information

4 Bytes

Session Number

Session

Total No.

TNO (track no.) is a binary value
Non-existing sessions are FFFFFFFFH
(when session number exceeds session total)

Equal to TOC read out start FAD in single
sessions

Start TNO

within

session

Session start frame address

External read out start frame
address

Title

Data

Data Name

Data Specification

TOC and Session Information

3.0

SEGA Confidential

7.2.4

Status and Report

1) Response Format

Command response is in the format below. Whether CD report returns as a
report depends on the command. Periodic response absolutely returns CD
report.

Status

Report

FAD

Flg

Rep

Cnt

Ctrl

Adr

TNO

CD Report

byte 0 1 2 3 4 5 6 7

Combined status and CD reports are called CD status information.

2) Status

A status of FFH indicates REJECT (abnormal command)
The status code is valid when WAIT (bit 7 = 1). Other bits (bit 4 to bit 6) are 0.

Title

Data

Data Name

Data Specification

Status and Report (1/2)

4.0

Value

Status

Explanation

00H

<BUSY>

Status currently changing

01H

<PAUSE>

Currently paused

02H

Standby (drive in suspended
status)

03H

<PLAY>

Playing CD

04H

<SEEK>

Seeking

05H

<SCAN>

Scanning

06H

<OPEN>

Tray is opened

07H

No disc

08H

<RETRY>

Currently retrying read

09H

<ERROR>

Read data error occurred

0AH

<FATAL>

Fatal error occurred

bit 7 6 5 4 3 2 1 0

Status code (CD drive status)

1: Periodic Response
1: Data Transfer Request
1: WAIT (execute reserve)

0: Command Responce
0: Not the same
0: ACK (command normal recieve)

System Library User's Guide

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3) CD Report

FAD

Flg

Rep

Cnt

Ctrl

Adr

TNO

CD Report

byte

1 2 3 4 5 6 7

FLG : 4 bit flag

bit 7 6 5 4

1 : CD-ROM 0 : CD-DA (or when seeking or scanning)

Rep Cnt : 4 bit repeat frequency. Notification range 0H ~ EH (0 ~ 14 times)
Ctrl Adr : CONTROL/ADR byte of subcode Q
TNO

: Track number of subcode Q (binary value, not BCD)

: Index number of subcode Q (binary value, not BCD)

FAD

: Frame address (in header information when CD-ROM,

otherwise, based on subcode Q)

4) CD Report content in every status

CD Report is invalid for REJECT and valid for WAIT.
CD drive status and CD report contents are shown below. The FFH rows mean
invalid values.

O: Current value. Seek Home: seek (stop) against home position.
When the standby time expires and the status changes from <PAUSE> to
<STANDBY>, the value when paused is saved.

Title

Data

Data Name

Data Specification

Status and Report (2/2)

4.0

Status

CD flag/repeat

Control/ADR

Track No.

Index No.

Frame address

<BUSY>

O / FFH

O / FFFFFFH

<PAUSE>

value at pause

(when seek home)

FFH

FFFFFFH

<PLAY>

<SEEK>

target position

<SCAN>

<OPEN>

FFH

FFFFFFH

FFH

FFFFFFH

<RETRY>

<ERROR>

FFH

FFFFFFH

<FATAL>

undefined

SEGA Confidential

5) When CD report content is an ineffective value

(a) The value immediately before the repeat frequency is saved. If changing to

a different status, returns to the retaind value.

(b) Moves to the start (FAD = 150) of the disk if the status changes from Seek

Home to <PAUSE>.

<PAUSE> status, returns to the retained value.

(d) Midway during the <BUSY> status, the ineffective value returns in some

cases when changing to a different status.

System Library User's Guide

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7.2.5

Subcode Information

1) Subcode Q Information

(a) When Adr = 1

Ctrl

Adr

TNO

byte 1 2 3 4 5 6 7 8 9 10

CRC

P_FAD

Q_FAD

Ctrl Adr : CONTROL/ADR byte
TNO

: Track No. (binary value not BCD)

: Index No. (binary value not BCD)

P_FAD

: Time within track (frame address format with track lead at 0)

Q_FAD

: Absolute time (frame address format with 00:00:00 at 0)

The content in each status is the same as for the CD report.
Values in read in and read out are shown in the table below.
(Can be acquired by multi-session)

Read in of the first session is Q_FAD = 000000H.
(Normally cannot be acquired).
(b) In other cases: the subcode Q value unchanged (10 bytes except CRC)

2) Subcode R~W Information

Pack

Packet (corresponds
to1 frame = 1 sector)
96 bytes

unused (padded by 0)

bit 7 6 5 4 3 2 1 0

R S T U V W

24 bytes

Subcode R~W is decoded in 1 pack units (24 bytes = 12 words).
The CD block has an internal pack buffer of 23 packs (short of 6 packets).

Title

Data

Data Name

Data Specification

Subcode Information

5.0

TNO

P_FAD

01H ~ 63H (1 ~ 99)

01H ~ 63H

Elapsed FAD within track

AAH (Read Out)

01H ~ 63H

Elapsed FAD within track

00H (Read In)

01H ~ 63H, A0H, A1H, A2H

000000H

SEGA Confidential

7.2.6

Data Type

1) Return Code

CdcRet ret . . . . . . Be sure ret is not the pointer.

3) Status

The retaining status of the CD communication interface is substituted in the
return code status together with all functions. Response status returnswhen
response is acquired by acquiring periodic response or issuing commands.
The holding status returns unchanged when a response cannot be acquired by
not issuing a command or error.

Title

Data

Data Name

Data Specification

CD Communication Function Return

Code

CdcRet

6.1

Access Macro

T y p e

Explanation

CDC_RET_ERR (ret)

Sint 16

Error Code

CDC_RET_STATUS (ret)

Uint 8

Status

2) Error Code

Constant Name

Explanation

CDC_ERR_OK

Normal (process continuation)

CDC_ERR_CMDBUSY

Command end flag is not 1

CDC_ERR_CMDNG

CMOK flag is not 1 when command is

issued

CDC_ERR_TMOUT

Time out (wait for response, wait for data
transfer ready)

CDC_ERR_PUT

Data transfer read wait by sector data
write. Could not reserve empty sectors.

CDC_ERR_REJECT

REJECT for command response

CDC_ERR_WAIT

WAIT for command response

CDC_ERR_TRNS

Abnormal data transfer size

CDC_ERR_PERI

Not a periodic response

CDC_ERR_PTYPE

Abnormal play, seek position type

System Library User's Guide

SEGA Confidential

Combine the CD block status and CD report to create CD status information.

1) CD Status Information

CdcStat *stat

2) CD Report CD flag and Repeat Count

bit 7 6 5 4 3 2 1 0

Repeat number (0H ~ EH: repeat 14 times)

1: CD-ROM 0: CD-DA (or when seeking or scanning

1) Hardware Information

CdcHw *hw

2) Hardware Flag

bit 7 6 5 4 3 2 1 0

1 : MPEG exists 0: not the same
1 : Hardware error occurs 0: Normal

Title

Data

Data Name

Data Specification

CD Status Information

CdcStat

6.2

Access Macro

Type

Explanation

CDC_STAT_STATUS (stat)

Uint 8

Status

CDC_STAT_FLGREP (stat)

Uint 8

CD report CD flag and repeat no.

CDC_STAT_CTLADR (stat)

Uint 8

CD report CONTROL/ADR byte

CDC_STAT_TNO (stat)

Uint 8

CD report track no. (binary value)

CDC_STAT_IDX (stat)

Uint 8

CD report index no. (binary value)

CDC_STAT_FAD (stat)

Sint 32

CD report frame address

Title

Data

Data Name

Data Specification

Hardware Information

CdcHw

6.3

Access Macro

Type

Explanation

CDC_HW_HFLAG (hw)

Uint 8

Hardware flag

CDC_HW_VER (hw)

Uint 8

CD block version information

CDC_HW_MPVER (hw)

Uint 8

MPEG version information

CDC_HW_DRV (hw)

Uint 8

CD drive information

CDC_HW_REV (hw)

Uint 8

CD block revision information

SEGA Confidential

Title

Data

Data Name

Data Specification

CD Position Parameters (1/2)

CdcPos

6.4

Access Macro

Type

Explanation

CDC_POS_PTYPE (pos)

Sint 32

Position type

CDC_POS_FAD (pos)

Sint 32

Frame address, FAD sector no.

CDC_POS_TNO (pos)

Uint 8

Track number

CDC_POS_IDX (pos)

Uint 8

Index number

System Library User's Guide

Constant Name

Explanation

CDC_PTYPE_DFL

Designates default values

For CD play : indicates disk start and end.
For seek: indicates home position.

CDC_PTYPE_FAD

Designates frame address

CDC_PTYPE_TNO

Designates track/index

CDC_PTYPE_NOCHG

Designates no change (no change in set values)

Designates the CD range of play (start and end positions) and is used in designating
the seek position.

1) Position Type

Default value, frame address, track/index, and no change can be designated at
position parameters. The constants (position type) below are used to select the
parameter.

Beginning of disc: FAD = 150(96H) position (2 seconds, 0 frame with absolute time)
End of disc:

FAD = readout start frame address (TOC information) - 1 position.

2) Position Paramters

CdcPos *pos

3) Setting Method

(a)

Designating

the default value

CdcPos pos;
CDC_POS_PTYPE (&pos)

= CDC_PTYPE_DFL;

(b)

Designating

the frame address

CDC_POS_PTYPE (&pos)

= CDC_PTYPE_FAD;

CDC_POS_FAD (&pos)

= fad;

/* frame address */

The end position is

designated

by sector number (FAD sector

number) from the starting FAD
(c)

Designating

the Track/Index

CDC_POS_PTYPE (&pos)

= CDC_PTYPE_TNO;

CDC_POS_TNO (&pos)

= tno;

/* track number */

CDC_POS_IDX (&pos)

= x;

/* index number */

(d)

Designating

No Change

CDC_POS_PTYPE (&pos)

= CDC_PTYPE_NOCHG;

SEGA Confidential

4) Execptions to Frame Address

The frame address is explained by the conditions below.

Relationship of start and end positions:

End FAD = Start FAD + FAD sector number - 1
(The held contents of the play range are the Start FAD and End FAD.)

5) Execptions to Track/Index

The track/index is explained by the conditions below.

TNO: track number, X: index number

X = 0 means designation of the track only. (track start/last index)
TNO = X = 0 is the default value of the position parameter.
(Start position: start of disc, End position: end of disc, Seek postion: home
postion)

6) Exceptions to the Play Range

The play range is retained if the end postion is smaller than the start position,
but the CD will not play. (For designating both frame address and track/index)

7) Meanings of Special Designations

Specifies seek position default value:

used as a stop command.
(seeks home position)

Specifies seek position no change:

used as a pause command.

Specifies play range no change:

used with pause cancel (retry CD play).

Title

Data

Data Name

Data Specification

CD Position Parameters (2/2)

CdcPos

6.4

Condition

Start and Seek Positions

End Position

FAD < disc start

FAD = disc start (150)

FAD = 150+FAD sector no. - 1

(when starting FAD <150)

FAD > disc end

FAD = disc end + 1
(equal to read out)

FAD = disc end

Condition

Start and Seek

Positions

End Position

TNO = 0 (track default
value)

TNO = disc start track

TNO = disc last track

X = 0 (index default
value)

X =1

X = 99(63H)

TNO < disc start track

TNO = disc start track

X = 1 (same as X = 0)

TNO = disc start track
X = 99 (same as X = 0 )

TNO > disc end track

TNO = disc end track

X = 1 (same as X = 0)

TNO = disc end track
X = 99 (same as X = 0 )

X does not exist

(from the next track)

(until track ends)

SEGA Confidential

Used to designate the play range and play mode when playing a CD.

1) Play Mode

When playing a CD, the maximum repeat count of the play segment and the
existence of pickup movement (play position) to the start position are
designated. The designation range of the maximum repeat count is 4 bits.
The default value is 0.

Title

Data

Data Name

Data Specification

CD Play Parameters

CdcPly

6.5

Value

Explanation

00H

No repeat (plays only one time)

01H ~ 0EH Repeat designation count (repeat 1 ~ 14

times)

0FH

Infinite repetitions

7FH

Does not change maximum repeat count

Constant Name

Explanation

CDC_PM_DFL

Play mode default value (no repeat, moves pickup)

CDC_PM_REP_NOCHG

No change in maximum repeat count

CDC_PM_PIC_NOMOV

Does not move pickup to start position
(<PAUSE> status when current position is outside play range)

CDC_PM_NOCHG

Play mode does not change (can change play range only)
Equal to (CDC_PM_REP_NOCHG : CDC_PM_PIC_NOMOV)

bit 7 6 5 4 3 2 1 0

Maximum Repeat Count

1: Does not move pickup to start position 0: Same movement

System Library User's Guide

SEGA Confidential

2) Play Parameters

CdcPly *ply

Access Macro

Type

Explanation

CDC_PLY_START (ply)

CdcPos

Play start position parameters

CDC_PLY_STYPE (ply)

Sint 32

Start position type

CDC_PLY_SFAD (ply)

Sint 32

Start position frame address

CDC_PLY_STNO (ply)

Uint 8

Start position track number

CDC_PLY_SIDX (ply)

Uint 8

Start position index number

CDC_PLY_END (ply)

CdcPos

Play end position parameters

CDC_PLY_ETYPE (ply)

Sint 32

End position type

CDC_PLY_EFAS (ply)

Sint 32

End position frame address sector
number

CDC_PLY_ETNO (ply)

Uint 8

End position track number

CDC_PLY_EIDX (ply)

Uint 8

End position index number

CDC_PLY_PMODE(ply)

Uint 8

Play mode (repeat designation,
pickup movement)

SEGA Confidential

3) Method for setting play parameters

Play parameters designate the play range and play mode. Play range is
designated by a combination of the position parameters of the start and end
positions.

(a) Track designation and frame address designation cannot be combined in the

play range. In such cases, REJECT is returned. All other play range combi-
nations are possible.

(b) All play range and play mode combinations are possible.
(c) The play range and maximum repeat count is held within the CD block and

are effective until reset.

(d) Default value: start of disc to end of disc, no repeat, moves pickup.

Examples of settings are shown below.

<KEY>

fad: frame address

fasnum: frame address sector number

tno 1: start track number

tno 2: end track number

x1: start index number

x2: end index number

Note 1:

fad + fasnum -1 is retained as the end postion.

Note 2:

Track and frame address designation cannot be combined even if there is no change on
the one hand.

4) Execptions to the Play Range

No play if the end postion is less than the start position. Becomes <PAUSE>
status same as play range exterior. The play range is held and the play mode is
also effective. (Pickup moves to the start position.)

N o . Play Method

Start Position

End Position

Comments

Track designation

tno 1, x1

tno 2, x2

Frame address
designation

fad

fasnum

note: 1

Play from first of disc

CDC_PTYPE_DFL

tno 2, x2

fasnum

Play until end of disc

tno 1, x1

fad

CDC_PTYPE_DFL

End position does not
change. (only the start
position changes)

tno 1, x1

fad

CDC_PTYPE_NOCHG

note: 2

Start position does not
change. (only the end
position changes)

CDC_PTYPE_NOCHG

tno 2, x2

fasnum

note: 2

Play is retried from the
current position without
changing the play range
and play mode.

CDC_PTYPE_NOCHG

CDC_PM_NOC

HG is

designated

the Play mode.

System Library User's Guide

SEGA Confidential

Used when setting/getting sub header conditions for a filter.

1) Sub header Conditions

dcSubh *subh

Mask pattern

Comparison object bit pattern.

Comparision Value

Comparison value of the bit designated
by the mask pattern.

Whether the submode and coding information is equal to the comparison value is
decided after the logical product of their repective mask patterns are taken.

Condition equation

(sm & SMMSK) == SMVAL

(ci & CIMSK) == CIVAL

Title

Data

Data Name

Data Specification

Sub header Conditions

CdcSubh

6.6

Access Macro

Type

Explanation

CDC_SUBH_FN (subh)

Uint 8

File Number

CDC_SUBH_CN (subh)

Uint 8

Channel Number

CDC_SUBH_SMMSK (subh)

Uint 8

Sub mode mask pattern

CDC_SUBH_SMVAL (subh)

Uint 8

Sub mode comparison value

CDC_SUBH_CIMSK (subh)

Uint 8

Coding information mask pattern

CDC_SUBH_CIVAL (subh)

Uint 8

Coding information comparison value

SEGA Confidential

2) Sub Mode

bit 7 6 5 4 3 2 1 0

(Same as CD-ROM XA sub mode byte)

EOR

(End OF Record)

V (Video)

A (Audio)

D (Data)

T (Trigger)

F (Form)

(Real Time Sector)

EOF (End

File)

1: Record end sector

1: Video

sector

1: Audio

sector

1: Data

sector

1: Trigger

1: Form 2, 0: Form 1

1: Real time sector

1: File end sector

Constant Name

Type

Explanation

CDC_SM_EOR

01H

Record end sector

CDC_SM_VIDEO

02H

Video sector

CDC_SM_AUDIO

04H

Audio sector

CDC_SM_DATA

08H

Data sector

CDC_SM_TRIG

10H

Trigger bit

CDC_SM_FORM

20H

Form bit (0: Form 1, 1: Form 2)

CDC_SM_RT

40H

Real time sector

CDC_SM_EOF

80H

File end sector

System Library User's Guide

SEGA Confidential

1) Sector Information

CdcSct *sct

1) File Information

CdcFile *file

*
When there is no directory record system information, the file
number becomes 0.

2) File Attributes

bit 7

1 : Yes directory

0 : no directory (note 1)

1 : Form 1 sector included

0 : not included

1 : Form 2 sector included

0 : not included

1 : Interleave sector included

0 : non-interleave

1 : CD-DA file

0 : CD-ROM file

1 : Yes d irectory file

0 : no directory file

Valid at CD-ROM

XA standard

Note 2

Note 1:

bit 1 is a directory bit of the file flag within the directory record and valid when there
is no system information (discriminant gives bit 7 priority)

Note 2:

bits 3 to 7 is attribute information conforming to CD-ROM XA standards, and bits 3 to
7 are 0 when there is no system information.

Title

Data

Data Name

Data Specification

Sector Information

CdcSct

6.7

Access Macro

T y p e

Explanation

CDC_SCT_FAD (sct)

Sint 32

Frame address

CDC_SCT_FN (sct)

Uint 8

File Number

CDC_SCT_CN (sct)

Uint 8

Channel Number

CDC_SCT_SM (sct)

Uint 8

Sub mode

CDC_SCT_CI (sct)

Uint 8

Coding information

Title

Data

Data Name

Data Specification

File Information

CdcFile

6.8

Access Macro

Type

Explanation

CDC_FILE_FAD (file)

Sint 32

File start frame address

CDC_FILE_SIZE (file)

Sint 32

File size (byte number)

CDC_FILE_UNIT (file)

Uint 8

File unit size

CDC_FILE_GAP (file)

Uint 8

Gap size

CDC_FILE_FN (file)

Uint 8

File number *

CDC_FILE_ATR (file)

Uint 8

File attributes

SEGA Confidential

8.0 Function Specifications

Function specifications of the CD Communication Interface are described.

1) Format

Reserved areas with the figure are indicated by a "" mark. Reserved areas
must be designated with a 0.

2) Initial Values of Parameters

Initial values of parameters held in the CD block are equal to the default
values designated by the host as long as they are not specially specified.

3) CD Status Information (Status and CD Report) Hold

The CD communication interface holds status and CD reports when a CD
block command is issued. Information is not held by a periodic response.
The intial value of all holding contents is 0. The functions that change the
holding status/CD report are listed below by symbol.

[SR] :

changes status and CD report

[S-]

changes status only

[--] : no

changes (no command issued)

Nothing changes when there is an error (When the error code is not CDC_ERR_OK).

4) Data Transfer Inside Functions

Among the information get functions, data transfered by the function interior
enters the function name as Tget. The method of data transfer is software
transfer by the CPU.

Example: Get TOC information (CDC_TgetToc)

These functions call the following functions internally.
· Data transfer waiting for start

(CDC_DataReady)

· Data transfer end

(CDC_DataEnd)

Title

Data

Function Name [SR]

Function Specification CD Play

CDC_CdPlay

2.1

System Library User's Guide

SEGA Confidential

8.1 List of Functions

Table 8.1 is a list of functions of the CD communication interface.

Table 8.1 List of CD Communication Interface Functions (1)

Function

Name

Number

CD Block Common

1.0

Get current CD status information

CDC_GetCurStat

1.1

Get previous CD status information

CDC_GetLastStat

1.2

Get periodic CD status information

CDC_GetPeriStat

1.3

Get hardware information

CDC_GetHwInfo

1.4

Get TOC information

CDC_TgetToc

1.5

Get session information

CDC_GetSes

1.6

Initialize CD block

CDC_CdInit

1.7

Open tray

CDC_CdOpen

1.8

Data transfer ready

CDC_DataReady

1.9

Data transfer end

CDC_DataEnd

1.10

CD Drive

2.0

CD play

CDC_CdPlay

2.1

Seek play position

CDC_CdSeek

2.2

Scan

CDC_CdScan

2.3

Subcode

3.0

Get subcode Q

CDC_TgetScdQch

3.1

Get Subcode R ~ W

CDC_TgetScdRwch

3.2

CD-ROM Device

4.0

Set connection point of CD device

CDC_CdSetCon

4.1

Get connection point of CD device

CDC_CdGetCon

4.2

Get buffer partition of last read sector

CDC_CdGetLastBuf

4.3

Selector

5.0

Set filter frame address range

CDC_SetFiltRange

5.1

Get filter frame address range

CDC_GetFiltRange

5.2

Set filter subheader conditions

CDC_SetFiltSubh

5.3

Get filter subheader conditions

CDC_GetFiltSubh

5.4

Set filter mode

CDC_SetFiltMode

5.5

Get filter mode

CDC_GetFiltMode

5.6

Set filter connection point

CDC_SetFiltCon

5.7

Get filter connection point

CDC_GetFiltCon

5.8

Reset selector (filter, partition)

CDC_ResetSelector

5.9

SEGA Confidential

Function

Name

Number

Buffer Information

6.0

Get CD buffer size

CDC_GetBufSiz

6.1

Get buffer partition sector number

CDC_GetSctNum

6.2

Calculate actual data size

CDC_CalActSiz

6.3

Get actual data size

CDC_GetActSiz

6.4

Get sector information

CDC_GetSctInfo

6.5

Execute frame address search

CDC_ExeFadSearch

6.6

Get frame address search results

CDC_GetFadSearch

6.7

Buffer Input/Output

7.0

Set sector length

CDC_SetSctLen

7.1

Get sector data

CDC_GetSctData

7.2

Delete sector data

CDC_DelSctData

7.3

Get and delete sector data

CDC_GetdelSctData

7.4

Write sector data

CDC_PutSctData

7.5

Copy sector data

CDC_CopySctData

7.6

Move sector data

CDC_MoveSctData

7.7

Get sector data copy/move error

CDC_GetCopyErr

7.8

CD Block File System

8.0

Change directory

CDC_ChgDir

8.1

Hold file information

CDC_ReadDir

8.2

Get holding file information range

CDC_GetFileScope

8.3

Get holding file information

CDC_TgetFileInfo

8.4

Read file

CDC_ReadFile

8.5

Stop file access

CDC_AbortFile

8.6

9.0

Get data transfer register pointer

CDC_GetDataPtr

9.1

Get interrupt factor register value

CDC_GetHirqReq

9.2

Clear interrupt factor register

CDC_ClrHirqReq

9.3

Get interrupt mask register value

CDC_GetHirqMsk

9.4

Set interrupt mask register

CDC_SetHirqMsk

9.5

Get MPEG register pointer

CDC_GetMpegPtr

9.6

Table 8.1 List of CD Communication Interface Functions (2)

System Library User's Guide

SEGA Confidential

8.2 Function Details

8.2.1

CD Block Common

Format:

CdcRet CDC_GetCurStat

(CdcStat *stat)

Input:

None

Output:

stat

: CD status information

Function value:

Returns the return code

Function:

Issues the get command of CD status information for the
CD block and gets current CD status information (status
and CD report).

Format:

CdcRet CDC_GetLastStat

(CdcStat *stat)

Input:

None

Output:

stat

: CD status information

Function value:

Returns the return code.

Function:

Gets CD status information for the previous CD block command.

Remarks:

If the CD communication interface issues a CD block
command, the status and CD report of that response is held.
This function returns the value being held.

Format:

CdcRet CDC_GetPeriStat

(CdcStat *stat)

Input:

None

Output:

stat

: CD status information

Function value:

Returns the return code.

Function:

Gets CD status information through periodic response.

Remarks:

Since the command for CD block is not issued, the load is
small and the polling process is possible.

Title

Function

Function Name

[SR] No.

Function
Specifications

Get current CD status information

CDC_GetCurStat

1.1

Title

Function

Function Name

[ -- ]

No.

Function
Specifications

Get previous CD status information

CDC_GetLastStat

1.2

Title

Function

Function Name

[ -- ]

No.

Function
Specifications

Get periodic CD status information

CDC_GetPeriStat

1.3

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Format:

CdcRet CDC_GetHwInfo

(CdcHw *hw)

Input:

None

Output:

: hardware information

Function value:

Returns the return code.

Function:

Gets CD block hardware information.

Format:

CdcRet CDC_TgetToc

(Uint32 *toc)

Input:

None

Output:

toc

: TOC information (204 words)

Function value:

Returns the return code.

Function:

Gets all TOC information (102 peices, 408 bytes)
Waits in the <OPEN> status and <NODISC> status

Example:

Uint 32 toc [102];

/* reserves TOC information store region */

ret = CDC_TgetToc(toc); /* get TOC information

Format:

dcRet CDC_GetSes

(Sint32 sesno, Uint32 *ses)

Input:

sesno : session number (0 ~ 99)

Output:

ses

: session information (2 words)

Function value:

Returns the return code.

Function:

Gets session information (4 bytes) of the designed session.
Waits in the <OPEN> status and <NODISC> status.

Title

Function

Function Name

[S- ]

No.

Function
Specifications

Get hardware information

CDC_GetHwInfo

1.4

Title

Function

Function Name

[S- ]

No.

Function
Specifications

Get TOC information

CDC_TgetToc

1.5

Title

Function

Function Name

[S- ]

No.

Function
Specifications

Get session information

CDC_GetSes

1.6

System Library User's Guide

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Format:

CdcRet CDC_CdInit

(Sint32 iflag, Sint32 stnby, Sint32 ecc,
Sint32 retry)

Input:

iflag

: initializing flag

(insignificant 8 bits are effective)

stnby : standby time

(insignificant 8 bits are effective)

ecc

: ECC frequency

(insignificant 8 bits are effective)

retry

: retry frequency

(insignificant 8 bits are effective)

Output:

none

Function value:

Returns the return code.

Function:

Initial setting of CD block.

1) Initializing flag

Designates each type of setting flag (8 bits) to the CD block.
When software is reset, all other initialized parameters are ignored and this
becomes the initial value.

bit 7

Initial value : 00H

1 : Reset CD block software

0 : not the same

1 : Decode of RW subcode

0 : not the same

1 : Doesn't confirm Mode 2 subheader 0 : the same
1 : Retry Form 2 read

0 : not the same

1 : CD-ROM data read standard speed 0 : 2X standard speed
1 : No change

0 : Change

(a)

Interrupt factor register ESEL flag becomes 1 when reset of software ends.

(b) Recognition of the Mode 2 subheader is used only in the correcting process

during CD-ROM decode. The selector always recognizes the subheader.
(decides conditions of the filter, selector length, etc.)

(c)

Data is output even if there is an error when Form 2 read is not retried.

(d) CD-ROM data read speed switches when changing to the <PAUSE> status.

When the CD-DA area is played, it automatically plays at standard speed.
The prior speed returns if the CD-ROM area is entered.

2) Standby Time

Designates the transition time from <PAUSE> to <STANDBY>.
Changes to <STANDBY> when the standby time of <PAUSE> expires.

Title

Function

Function Name

[SR]

No.

Function
Specifications

Initialize CDblock (1/2)

CDC_CdInit

1.7

Set Value

Description

0000H

180 seconds ......initial value

0001H ~ FFFEH

Transition time (in seconds)

FFFFH

No change in settings

SEGA Confidential

3) ECC Frequency

Designates the number of repetitions of the ECC process (PQ once each) during
CD-ROM decode.

4) Retry Frequency

Designates the number of retries of the same sector if an error occurs during
CD-ROM decode.

bit 7

Frequency indicated by insignificant 4 bits.

1 : Data output even if error occurs

0 : Stops output

1 : Infinite number of retrys

0 : Definte number

Frequency (0 ~ 15 times)

5) Tray Open/Close

Closes the Tray when in the <OPEN> status.

When automatic format (front loading) : CD block automatically closes tray.

When manual format (top loading) : <BUSY> status until closed by manual.

Tray open when in the <NODISC> status. (See Tray Open)
Tray open and close operates the same for CD play, seek play position, and scan.

Remarks:

All command issues are prohibited while the software is being reset.

Title

Function

Function Name

[SR]

No.

Function
Specifications

Initialize CD block (2/2)

CDC_CdInit

1.7

Set Value

Description

00H

ECC is processed a maximum of only 1 time in real time .....
initial value.

01H ~ 05H

When an error exists after the ECC process, maximum number
of repetitions (total of 2 to 6 times).

80H

No ECC process

FFH

No change in settings

Set Value

Description

00H

Without retrying, stops data output (becomes <ERROR>) .....
initial value.

01H ~ 0FH ( )

Retries designated number of times, data output stops if there

is an error (becomes <ERROR>).

40H

Data is output without retrying

41H ~ 4FH ( )

Retries designated number of times, data is output even if
there is an error.

80H

Infinite number of retries

FFH

No change in settings

System Library User's Guide

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Format:

CdcRet CDC_CdOpen (void)

Input:

none

Output:

none

Function value:

Returns the return code.

Function:

Stops the CD drive and opens the tray

When automatic format (front loading) : CD block automatically
opens tray.

When manual format (top loading) : <BUSY> status until opened
by manual.

Remarks:

When the tray is opened, DCHG of the interrupt factor register
and EFLS flag become 1. The timing is before the <OPEN>status.
(Same for when opening manually.)

Format:

CdcRet CDC_DataReady (Sint32 dtype)

Input:

dtype

: transfer ready type

Output:

none

Function value:

Returns the return code.

Function:

Waits until data transfer ready is enabled. Data can be transfered
after ready is finished. If data is transfered, data transfer end must be
executed.

1) Transfer Ready Type

2) Transfer Ready Process

Waits until DRDY of the interrupt factor register becomes 1, and clears 0 if it
becomes 1. If empty sectors can not be reserved when writing, the EHST flag of
the interrupt factor register becomes 1. In this case, CDC_ERR_PUT error is
returned.

Remarks:

When an error is caused by ready, there is no need to execute data
transfer end. It

will be automatically executed inside the ready function.

Title

Function

Function Name

[SR]

No.

Function
Specifications

Open tray

CDC_CdOpen

1.8

Title

Function

Function Name

[S-]

No.

Function
Specifications

Data transfer ready

CDC_DataReady

1.9

Value

Description

CDC_DRDY_GET

Designated when getting data. (CD block

host)

CDC_DRDY_PUT

Designated when writing data. (host

CD block)

SEGA Confidential

Format:

CdcRet CDC_DataEnd (Sint32 *cdwnum)

Input:

none

Output:

cdwnum

: CD block transfer word number

Function value:

Returns the return code.

Function:

Instructs the end of data transfer for the CD block. Data transfer
can be stopped while in process.

1) CD Block Transfer Word Number

Returns the word number of effective data transfered by the CD block.The
normal word number can not be exceeded (entire number of words that should
be transfered).

2) Relationship of Transfer Word Number

Data transfer conditions can be checked by comparing the host transfer word
number (word number transfered by the host until data transfer end is
executed) and the CD block transfer word number.

Transfer interrupt :

Stops data transfer while in progress.

Transfer all

: All data is transfered.

Excess transfer

: Normal word number is exceeded and

transfered (Excess part is transfered as
dummy data).

Title

Function

Function Name

[S-]

No.

Function
Specifications

Data transfer end

CDC_DataEnd

1.10

Constant Name

Description

CDC_DEND_ERR

Error occurred by data transfer

Data transfer end is executed even though it isn't time for
transfer.

Transfer Conditions

Host Transfer Word Number

CD Block Transfer Word Number (cdwnum)

(Host Word Number)

When gettng (CD

host)

When writing (host

CD)

Transfer interrupt

host word no. < normal word no.

cdwnum > host word number

cdwnum = host word number

Transfer all

host word no. = normal word no.

cdwnum = normal word number = host word number

Excess transfer

host word no. > normal word no.

cdwnum = normal word number < host word number

System Library User's Guide

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8.2.2

CD Drive

For tray open/close in the <OPEN> and <NODISC> statuses see Initialize CD block.

Format:

CdcRet CDC_CdPlay (CdcPly *ply)

Input:

ply

: play parameters

Output:

none

Function value:

Returns the return code.

Function:

Plays CDs according to the designated play parameters.
Plays music in the CD-DA area. Reads sector data in the
CD-ROM area.

Remarks:

In playing CD-DA, mute is canceled 4 frames prior to the start
position to prevent the start of a song from being cut off.

Example:

(1) Frame Address Designation

CdcPly ply;

/* definition of play parameter variable */

CDC_PLY_STYPE (&ply)

= CDC_PTYPE_FAD;

CDC_PLY_SFAD (&ply)

= fad;

/* start frame address

CDC_PLY_ETYPE (&ply)

= CDC_PTYPE_FAD;

CDC_PLY_EFAS (&ply)

= fasnum;

/* frame address sector number

CDC_PLY_PMODE (&ply) = pmode;

/* play mode

ret = CDC_CdPlay (&ply);

/* play start

(2) Track/Index Designation

CDC_PLY_STYPE (&ply)

= CDC_PTYPE_TNO;

CDC_PLY_STNO (&ply)

= tno1;

/* start track number

CDC_PLY_SIDX (&ply)

= x1;

/* start index number

CDC_PLY_ETYPE (&ply)

= CDC_PTYPE TNO;

CDC_PLY_ETNO (&ply)

= tno2;

/* end track number

CDC _PLY_EIDX (&ply)

= x2;

/* end index number

CDC _PLY_PMODE (&ply) = pmode;

/* play mode

(3) Default Value Designation

CDC_PLY_STYPE (&ply)

= CDC_PTYPE_DFL; /* start position is first of disc

CDC_PLY_ETYPE (&ply)

= CDC_PTYPE_DFL; /* end position is end of disc

CDC_PLY_PMODE (&ply) = CDC_PM_DFL;

/* no repeat, move pickup

(4) CD Play Restart (unchanged selection: play from current position)

.... cancel pause

CDC_PLY_STYPE (&ply)

= CDC_PTYPE_NOCHG;

CDC_PLY_ETYPE (&ply)

= CDC_PTYPE_NOCHG;

CDC_PLY_PMODE (&ply) = CDC_PM_NOCHG;

Title

Function

Function Name

[SR]

No.

Function
Specifications

CD play

CDC_CdPlay

2.1

SEGA Confidential

Format:

CdcRet CDC_CdSeek

(CdcPos *pos)

Input:

pos

: position parameters

Output:

none

Function value:

Returns the return code.

Function:

Moves (seeks) the play position (pickup) according to the designated
position parameters.

Example:

Frame Address Designation

CdcPos pos;

/* definition of position parameter variable */

CDC_POS_PTYPE (&pos) =CDC_PTYPE_FAD;

CDC_POS_FAD (&pos )= fad;

/* frame address

ret = CDC_CdSeek (&pos);

/* seek start

Track/Index Designation

CDC_POS_PTYPE (&pos)

CDC_PTYPE_TNO;

CDC_POS_TNO (&pos)

tno;

/* track number

CDC_POS_IDX (&pos);

/* index number

CD Play Stop (Default vlaue designation: Seek home position)...... Stop

CDC_POS_PTYPE (&pos) = CDC_PTYPE_DFL;

Pause CD Play (No changed selection: seek current position) ......Pause

CDC_POS_PTYPE (&pos) = CDC_PTYPE_NOCHG;

Title

Function

Function Name

[SR]

No.

Function
Specifications

Seek play position

CDC_CdSeek

2.2

System Library User's Guide

SEGA Confidential

Format:

CdcRet CDC_CdScan

(Sint32 scandir)

Input:

scandir

: Scan direction

Output:

none

Function value:

Returns the return code.

Function:

Scans the CD.
Scanning continues until a CD drive command (CD play, seek, etc.) is
issued. Scan is canceled and a pause occurs if the play range is
exceeded. The pause position at that time is undefined.

1) Scan Direction

2) Sound Output

If scanning from the <PLAY> status, -12 dB sounds are output in the CD-
DA region. Sound is muted if scanning in the CD-ROM area or in the <PAUSE>
status. If the scan direction in near the play range boundary is reversed, the
sound may not be output.

Remarks:

When the CD-ROM area is scanned, sector data will not be read.

Title

Function

Function Name

[SR]

No.

Function
Specifications

Scan

CDC_CdScan

2.3

Constant Name

Description

CDC_SCAN_FWD

Fast forward scan (forward direction)

CDC_SCAN_RVS

Fast reverse scan (reverse direction)

SEGA Confidential

8.2.3

Subcode

Format:

CdcRet CDC_TgetScdQch

(Uint16 *qcode)

Input:

none

Output:

qcode

: Subcode Q information (5 words)

Function value:

Returns the return code.

Function:

Gets subcode Q channel information
(10 bytes other than CRC)

Format:

CdcRet CDC_TgetScdRwch

(Uint16 *rwcode, Sint32 *scdflag)

Input:

none

Output:

rwcode

: Subcode R ~ W information (12 words)

scdflag

: Subcode flag (effective bits are insignificant)

Function value:

Returns the return code.

Function:

Gets subcode R~W channel information (1 pack of 24 bytes).

(1) Subcode Flag

Shows error conditions of retrieved subcode R ~ W information (pack
data).

bit 7

1 : Pack data error

0 : Normal

1 : Overrun error

0 : Normal

Remarks:

Pack data can not exceed retrieval of 16 packs in one time frame
(13.3 ms). Returns to WAIT if the pack buffer is empty and there is
no pack data.

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get subcode Q

CDC_TgetScdQch

3.1

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get subcode R ~ W

CDC_TgetScdRwch

3.2

System Library User's Guide

SEGA Confidential

8.2.4

CD-ROM Device

Format:

CdcRet CDC_CdSetCon

(Sint32 filtno)

Input:

filtno

Connection destination filter number

(CDC_NUL_SEL : display non-connection)

Output:

none

Function value:

Returns the return code.

Function:

Sets the connection destination (filter) of the CD device.
Connection is separated if CDC_NUL_SEL is selected.

Format:

CdcRet CDC_CdGetCon

(Sint32 *filtno)

Input:

none

Output:

filtno

Connection destination filter number

(CDC_NUL_SEL : displays non-connection)

Function value:

Returns the return code.

Function:

Gets the connection destination (filter) of the CD device.
Returns CDC_NUL_SEL if there is no connection.

Format:

CdcRet CDC_CdGetLastBuf

(Sint32 *bufno)

Input:

none

Output:

bufno

Storage destination buffer partition number

(CDC_NUL_SEL : displays non-storage)

Function value:

Returns the return code.

Function:

Gets the buffer partition number of the storage destination of the
sector last read from the CD.

Title

Function

Function Name

[SR]

No.

Function
Specifications

Set connection destination of CD device

CDC_CdSetCon

4.1

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get connection destination of CD device

CDC_CdGetCon

4.2

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get buffer partition of last read sector

CDC_CdGetLastBuf

4.3

SEGA Confidential

8.2.5

Selector

See selector reset for the initial value of the selector set parameters.

Format:

CdcRet CDC_SetFiltRange

(Sint32 filtno, Sint32 fad,

Sint32 fasnum)

Input:

filtno

: filter number

fad

: starting frame address

fasnum

: frame address sector number

(0: effective FAD range does not exist)

Output:

none

Function value:

Returns the return code.

Function:

Sets the frame address range for the filter. When fasnum = 0, all
sectors are output to false output connectors if the FAD range of
the filter mode is effective.

Format:

CdcRet CDC_GetFiltRange

(Sint32 filtno, Sint32 *fad,

Sint32 *fasnum)

Input:

filtno

: filter number

Output:

fad

: starting frame address

fasnum

: frame address sector number

Function value:

Returns the return code.

Function:

Gets the frame address range for the filter.

Format:

CdcRet CDC_SetFiltSubh

(Sint32 filtno, CdcSubh *subh)

Input:

filtno

: filter number

subh

: subheader conditions

Output:

none

Function value:

Returns the return code.

Function:

Sets subheader conditions for the filter.

Format:

CdcRet CDC_GetFiltSubh

(Sint32 filtno, CdcSubh *subh)

Input:

filtno

: filter number

Output:

subh

: subheader conditions

Function value:

Returns the return code.

Function:

Gets subheader conditions for the filter.

Title

Function

Function Name

[SR]

No.

Function Specs Set filter frame address range

CDC_SetFiltRange

5.1

Title

Function

Function Name

[S-]

No.

Function Specs Get filter frame address range

CDC_GetFiltRange

5.2

Title

Function

Function Name

[SR]

No.

Function Specs Set filter subheader conditions

CDC_SetFiltSubh

5.3

Title

Function

Function Name

[S-]

No.

Function Specs Get filter subheader conditions

CDC_GetFiltSubh

5.4

System Library User's Guide

SEGA Confidential

Format:

CdcRet CDC_SetFiltMode

(Sint32 filtno, Sint32 fmode)

Input:

filtno

: filter number

fmode

: filter mode (insignificant 8 bits are effective)

Output:

none

Function value:

Returns the return code.

Function:

Sets the filter mode for the filter.

1) Filter mode

bit 7

1 : Select file number (FN)
0 : not the same
1 : Select channel number (CN)
0 : not the same
1 : Select submode (SM)
0 : not the same
1 : Select coding information (CI)
0 : not the same
1 : Reverse subheader conditions
0 : not the same reversal

1 : Select frame address range
0 : not the same

1 : Initialize filter conditions (return to intial values)
0 : not the same initialization

2) Reverse Subheader Conditions

If subheader conditions are reversed, the output destination will be the opposite
of what is normal for subheader conditions. In short, sectors that correspond to
subheader conditions are output to false output connectors, and sectors that do
not correspond to subheader conditions are output to true output connectors
(conditions below.)

Output to true output connector:

filter FAD range coincides and
subheader conditions do not coincide.

Output to false output connector: filter FAD range does not coincide

or subheader conditions coincide.

3) Initialing Filter Conditions

When filter conditions are initialized, other bit selections are ignored and the
initial values below are set.

Frame address range

: Starting FAD = 0, FAD sector number = 0

Subheader conditions : FN, CN, SMMSK, SMVAL, CIMSK, CIVAL are all 0

Filter mode

: All bits = 0

Title

Function

Function Name

[SR]

No.

Function Specs Set filter mode

CDC_SetFiltMode

5.5

SEGA Confidential

Format:

CdcRet CDC_GetFiltMode

(Sint32 filtno, Sint32 *fmode)

Input:

filtno

: filter number

Output:

fmode

: filter mode (insignificant 8 bits are effective)

Function value:

Returns the return code.

Function:

Gets the filter mode for the filter.

Filter mode

bit 7

1 : Select file number (FN)
0 : not the same
1 : Select channel number (CN)
0 : not the same
1 : Select submode (SM)
0 : not the same
1 : Select coding information (CI)
0 : not the same

1 : Select frame address range
0 : not the same

1 : Reverse subheader conditions
0 : not the same reversal

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get filter mode

CDC_GetFiltMode

5.6

System Library User's Guide

SEGA Confidential

Format:

CdcRet CDC_SetFiltCon

(Sint32 filtno, Sint32 cflag, Sint32 bufno, Sint32 flnout)

Input:

filtno

: filter number

cflag

: filter connection flag (insignificant 8 bits are effective)

bufno

: buffer partition no.of true output connector connection

destination (CDC_NUL_SEL : disconnected)

flnout

: filter number of false output connector connection

destination (CDC_NUL_SEL : disconnected)

Output:

none

Function value:

Returns the return code.

Function:

Sets the connection destination below for the filter. Connections are
disconnected if CDC_NUL_SEL is specified.

true output connector and buffer partition input connector

false output connector and other filter input connectors

Filter Connection Flag

bit 7

True output connector set flag
0 : No change in connection conditions
1 : Change the same (connect/disconnect to
buffer

partition)

False output connector set flag
0 : No change in connection conditions
1 : Change the same (connect/disconnect to filter)

filter fin

true output connector

flnout

false output connector

Format:

CdcRet CDC_GetFiltCon

(Sint32 filtno, Sint32 *bufno, Sint32 flnout)

Input:

filtno

: filter number

Output:

bufno

: buffer partition no. of true output connector connection

destination (CDC_NUL_SEL : not connected)

flnout

: filter number of false output connector connection

destination (CDC_NUL_SEL : not connected)

Function value:

Returns the return code.

Function:

Gets the filter connection destination. When not connected returns
CDC_NUL_SEL.

Title

Function

Function Name

[SR]

No.

Function Specs Set filter connection destination

CDC_SetFiltCon

5.7

Title

Function

Function Name

[S-]

No.

Function Specs Get filter connection destination

CDC_GetFiltCon

5.8

SEGA Confidential

Format:

CdcRet CDC_ResetSelector

(Sint32 rflag, Sint32 bufno)

Input:

rflag

: reset flag (insignificant 8 bits are effective)

bufno

: buffer partition number

Output:

none

Function value:

Returns the return code.

Function:

Initializes selector set conditions according to the reset flag value.

When reset flag = 0

: All specified buffer partition data is cleared

When reset flag

: Buffer partition number is ignored

1) Reset Flag

bit 7

1 : Initializes data of all buffer partitions
0 : not the same initialization

1 : Initializes all partition output connectors
0 : not the same initialization

1 : Initializes all filter conditions
0 : not the same initialization
1 : Initializes all filter input connectors
0 : not the same initialization
1 : Initializes true output connector of all filters
0 : not the same initialization
1 : Initializes false output connector of all filters
0 : not the same initialization

2) Initial Values
The following initial values are set for all selectors by initialization.

Buffer partition data

: All cleared (all data within the CD buffer is

cleared)

Partition output connector

: Status: All unconnected

Filter conditions

: Similar to initialization by "set filter mode"

Filter input connector

: Status: All unconnected

True output connector

: buffer partition and same number companion

filters are connected

False output connector

: Status: All unconnected

Title

Function

Function Name

[SR]

No.

Function Specs Resert selector (filter, partition)

CDC_ResetSelector

5.9

System Library User's Guide

SEGA Confidential

8.2.6

Buffer Information

Format:

CdcRet CDC_GetBufSiz

(Sint32 *totalsiz, Sint32 *bufnum, Sint32 *freesiz)

Input:

none

Output:

totalsiz

: total buffer size (sector units, 200 sectors = C8H)

bufnum

: total buffer partition number (24 partitions = 18H)

freesiz

: empty buffer size (sector units)

Function value:

Returns the return code.

Function:

Gets the Cd buffer total size and buffer partition number (both are
fixed values), also the current space size. The selector number (or
filter number) is equal to the total buffer partiton number.

Remarks:

Even if the space size is 0, the buffer does not need to be full since
there are sectors being used by the system.

Format:

CdcRet CDC_GetSctNum

(Sint32 bufno, Sint32 *snum)

Input:

bufno

: buffer partition number

Output:

snum

: sector number within buffer partition

(buffer partition size)

Function value:

Returns the return code.

Function:

Gets current sector number (buffer partition size) of buffer partition.

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get buffer partiton sector number

CDC_GetSctNum

6.2

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get CD buffer size

CDC_GetBufSiz

6.1

SEGA Confidential

Format:

CdcRet CDC_CalActSiz

(Sint32 bufno, Sint32 spos, Sint32 snum)

Input:

bufno

: buffer partition number

spos

: sector postion (CDC_SPOS_END : shows the

partition's last sector)

snum

: sector number (CDC_SNUM_END : shows the

sector number from spos to the last partition)

Output:

none

Function value:

Returns the return code.

Function:

Calculates the actual data size (word number when fetched to host) of
the buffer partition designated sector range, and holds that result.
Executes the setting of the sector length to set the length of 1 sector.

Remarks:

Connectors already connected to the partition output are disconnected.
Executes "get actual data size" to get the calculation result of the actual
data size.

Format:

CdcRet CDC_GetActSiz

(Sint32 *actwsiz)

Input:

none

Output:

actwsiz

: actual data size (word units)

Function value:

Returns the return code.

Function:

Gets the actual data size (initial value of 0) held by the CD block.

Format:

CdcRet CDC_GetSctInfo

(Sint32 bufno, Sint32 spos, CdcSct *sct)

Input:

bufno : buffer partition number
spos

: sector position (CDC_SPOS_END : shows the

partition's last sector)

Output:

sct

: sector information

Function value:

Returns the return code.

Function:

Gets header information (FAD) and subheader information of buffer
partition designated sectors.

Title

Function

Function Name

[SR]

No.

Function
Specifications

Calculation of actual data size

CDC_CalActSiz

6.3

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get actual data size

CDC_GetActSiz

6.4

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get sector information

CDC_GetSctInfo

6.5

System Library User's Guide

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Format:

CdcRet CDC_ExeFadSearch

(Sint32 bufno, Sint32 spos, Sint32 fad)

Input:

bufno : buffer partition number
spos

: sector position (CDC_SPOS_END : shows the

partition's last sector)

fad

: frame address

Output:

none

Function value:

Returns the return code.

Function:

Starting at the designated sector position in the buffer partition, with
the frame address as the key, the sector is retrieved and the result
retained.

1) Direction of retrieval

Retrieves in the direction of the buffer partition (from the
smaller to larger sector position.)

2) Retrieval result

Contents to be held as retrieval results include the buffer
partition number, retrieved sector position, and the frame
address of that sector.

3) Retrieval conditions

When a FAD that coincides does not exist, the nearest
sector not exceeding the designated FAD is used. Therefore,
retrieval resultant FAD is the greatest FAD that satisfies FAD

designated FAD. When there is no sector that satisfies this condi-
tion or when retrieval can not be done because of an error, the
sector position of the retrieval results is CDC_SOPS_END.

Remarks:

Connector that is already connected to the partition output is
disconnected. The retrieval result executes to get the frame address
retrieval result.

Format:

CdcRet CDC_GetFadSearch

(Sint32 *bufno, Sint32 *spos, Sint32 *fad)

Input:

none

Output:

bufno : buffer partition number
spos

: sector position (CDC_SPOS_END : no applicable

sector shown)

fad

: frame address

Function value:

Returns the return code.

Function:

Gets frame address search results (initial values all 0) held by the CD
block.

Title

Function

Function Name

[S-]

No.

Function Specs Get frame address search results

CDC_GetFadSearch

6.7

Title

Function

Function Name

[SR]

No.

Function Specs Execute frame address search

CDC_ExeFadSearch

6.6

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8.2.7

Buffer Input/Output

Each buffer input/output function (get sector data, delete, write, copy, move) in-
cludes the connector connection process. In other words, by issuing 1 command, the
device and selector connections and flow in and out complex processes are done.
Connectors connected to the partition output connector are disconnected.

Format:

CdcRet CDC_SetSctLen

(Sint32 getslen, Sint32 putslen)

Input:

getslen

sector length when fetching

putslen

sector length when writing

Output:

none

Function value:

Returns the return code.

Function:

Sets the length of one sector in the next cases.

Gets sector data (CD buffer to host)

Writes sector data (host to CD buffer)

Sector Length

Remarks:

The set "sector length when fetching" is also reflected in "Calculation
of actual data size."

Title

Function

Function Name

[SR]

No.

Function
Specifications

Set sector length

CDC_SetSctLen

7.1

Constant Name

Description

CDC_SLEN_2048

2048 bytes (user data) ....... initial value
when fetched, 2324 bytes if mode 2 form 2

CDC_SLEN_2336

2336 bytes (up to subheader)

CDC_SLEN_2340

2340 bytes (up to header)

CDC_SLEN_2352

2352 bytes (entire sector)

CDC_SLEN_NOCHG

No change

System Library User's Guide

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Format:

CdcRet CDC_GetSctData

(Sint32 bufno, Sint32 spos, Sint 32 snum)

Input:

bufno :

buffer partition number

spos

sector position (CDC_SPOS_END : shows the
partition's last sector)

snum :

sector number (CDC_SNUM_END : shows the sector
number from spos to the last partition)

Output:

none

Function value:

Returns the return code.

Function:

Gets sector data from the designated sector range of the buffer partition.

Remarks:

After executing the function, data must be transferred and fetched.

Format:

CdcRet CDC_DelSctData

(Sint32 bufno, Sint32 spos, Sint 32 snum)

Input:

bufno :

buffer partition number

spos

sector position (CDC_SPOS_END : shows the
partition's last sector)

snum :

sector number (CDC_SNUM_END : shows the
sector number from spos to the last partition)

Output:

none

Function value:

Returns the return code.

Function:

Deletes sector data of the designated sector range of the buffer partition.

Remarks:

Sector positions after data is deleted advance in order.

Format:

CdcRet CDC_GetdelSctData

(Sint32 bufno, Sint32 spos, Sint 32 snum)

Input:

bufno :

buffer partition number

spos

sector position (CDC_SPOS_END : shows the
partition's last sector)

snum

sector number (CDC_SNUM_END : shows the
sector number from spos to the last partition)

Output:

none

Function value:

Returns the return code.

Function:

Gets data from the designaed sector range of the buffer partition.
Sector data of the designated sector range is deleted from the buffer
partition.

Remarks:

After the function is executed, data must be transferred and fetched.
Even if all data is transferred without being fetched, all data of the
designated sector range is deleted.

Title

Function

Function Name

[SR]

No.

Function Specs Get sector data

CDC_GetSctData

7.2

Title

Function

Function Name

[SR]

No.

Function Specs Delete sector data

CDC_DelSctData

7.3

Title

Function

Function Name

[SR]

No.

Function Specs Get and delete sector data

CDC_GetdelSctData

7.4

SEGA Confidential

Title

Function

Function Name

[S- ]

No.

Function Specs Write sector data

CDC_PutSctData

7.5

Format:

CdcRet CDC_PutSctData

(Sint32 filtno, Sint32 snum)

Input:

filtno

filter number

snum

sector number

Output:

none

Function value:

Returns the return code.

Function:

Writes sector data to the designated filter.

Remarks:

Data must be transferred and written after the function is executed.
Data of the designated sector number is written even if data transfer
is interrupted. Values except for transferred data are not fixed.

Format:

CdcRet CDC_CopySctData

(Sint32 srcbn, Sint32 spos, Sint32 snum, Sint32 dstfln)

Input:

srcbn

copy source buffer partition number

spos

sector postion (CDC_SPOS_END : shows the
partition's last sector)

snum

sector number (CDC_SNUM_END : shows the
sector number from spos to the last partition)

dstfln

copy destination filter number

Output:

none

Function value:

Returns the return code.

Function:

Copies sector data from designated sector range of the buffer
partition. (Copies in between selectors.)

Format:

CdcRet CDC_MoveSctData

(Sint32 srcbn, Sint32 spos, Sint32 snum, Sint32 dstfln)

Input:

srcbn

move source buffer partition number

spos

sector postion (CDC_SPOS_END : shows the
partition's last sector)

snum

sector number (CDC_SNUM_END : shows the
sector number from spos to the last partition)

dstfln

copy destination filter number

Output:

none

Function value:

Returns the return code.

Function:

Moves sector data from designated sector range of the buffer
partition. (Moves in between selectors.)

Title

Function

Function Name

[SR]

No.

Function Specs Copy sector data

CDC_CopySctData

7.6

Title

Function

Function Name

[SR]

No.

Function Specs Move sector data

CDC_MoveSctData

7.7

System Library User's Guide

SEGA Confidential

Title

Function

Function Name

[SR]

No.

Function
Specifications

Get sector data copy/move error

CDC_GetCopyErr

7.8

Format:

CdcRet CDC_GetCopyErr

(Sint32 *cpyerr)

Input:

none

Output:

cpyerr : copy/move error information

Function value:

Returns the return code.

Function:

Gets sector data copy/move error information.

Copy/Move Error Information

Constant Name

Description

CDC_COPY_OK

Normal end ...... initial value

CDC_COPY_NG

Error is caused

Selector is disconnected during copy/move

No more space in buffer

CDC_COPY_BUSY

Copy/Move process is in progress

SEGA Confidential

8 . 2 . 8

CD Block File System

Title

Function

Function Name

[SR]

No.

Function
Specifications

Change directory

CDC_ChgDir

8.1

Format:

CdcRet CDC_ChgDir

(Sint32 filtno, Sint32 fid)

Input:

filtno

: filter number

fid

: file identifier of the directory file

(CDC_NUL_FID : root directory)

Output:

none

Function value:

Returns the return code.

Function:

Moves the current directory to the directory shown by the
designated file identifier. Moves to the root directory if
CDC_NUL_FID is specified in the file identifier.
When moved, it reads directory record, and retains a maximum of
254 files worth of data from the start (256 files if including parent
and own). Returns REJECT when directory is not designated by
the file identifier.

Remarks:

The CD block file system uses the selector in the operation. The
operation selector designates through the filter number.

Title

Function

Function Name

[SR]

No.

Function
Specifications

Hold file information

CDC_ReadDir

8.2

Format:

CdcRet CDC_ReadDir

(Sint32 filtno, Sint32 fid)

Input:

filtno

: filter number

fid

: file identifier

Output:

none

Function value:

Returns the return code.

Function:

Reads the directory record of the current directory and holds up
to 254 pieces of file information after the designated file identifier
(own and parent are always retained).

Remarks:

The CD block file system uses the selector in the operation. The
operation selector designates through the filter number.

SEGA Confidential

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get holding file information range

CDC_GetFileScope

8.3

Format:

CdcRet CDC_GetFileScope

(Sint32 *fid, Sint32 *infnum)

Input:

none

Output:

fid

: first file identifier being held

infnum

: number of file information being held

Function value:

Returns the return code.

Function:

Returns the file information range held by the current CD block.

Remarks:

Since the self and parent directories are always held, they are not
included in the file information number.

Title

Function

Function Name

[S-]

No.

Function
Specifications

Get holding file information

CDC_TgetFileInfo

8.4

Format:

CdcRet CDC_TgetFileInfo

(Sint32 fid, CdcFile *file)

Input:

fid

: file identifier (CDC_NUL_FID : shows entire file

information)

Output:

file

: file information

Function value:

Returns the return code.

Function:

Obtains file information (12 bytes) of the indicated file
identifier. Obtains all file information (up to 254 pieces) held in
the CD block if CDC_NUL_FID is designated in the file
identifier.

Example:

CdcFile file;

/* Reserves information storage area of 1 file*/

ret = CDC_TgetFileInfo (fid, &file) ;

CdcFile file[256];

/* Reserves information storage area of all files */

ret = CDC_TgetFileInfo (CDC_NUL_FID, file) ;

Title

Function

Function Name

[SR]

No.

Function
Specifications

Read file

CDC_ReadFile

8.5

Format:

CdcRet CDC_ReadFile

(Sint32 filtno, Sint32 fid, Sint32 offset)

Input:

filtno : filter number
fid

: file identifier

offset : logical offset from first of file (sector units)

Output:

none

Function value:

Returns the return code.

Function:

Reads the designated file. The read destination selector is
designated by the filter number.

SEGA Confidential

Title

Function

Function Name

[SR]

No.

Function
Specifications

Stop file access

CDC_AbortFile

8.6

Format:

CdcRet CDC_AbortFile

(void)

Input:

none

Output:

none

Function value:

Returns the return code.

Function:

Stops file access by each function (directory move, file
information hold, and file read) of the CD block file system.
Pauses the CD drive, and the EFLS flag of the interrupt factor
register becomes 1.

Remarks:

Even if file access is stopped, the buffer partition is not cleared
and the selector is not initialized. File information being held is
destroyed if directory-move and file-information-hold are
stopped. File access is also stopped when the tray is opened.

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8 . 2 . 9

Register Access

Title

Function

Function Name

[ -- ]

No.

Function Specs Get data transfer register pointer

CDC_GetDataPtr

9.1

Format:

Uint16 *CDC_GetDataPtr

(void)

Input:

none

Output:

none

Function value:

Function:

Gets the data transfer register (DATATRNS) pointer.

Title

Function

Function Name

[ -- ]

No.

Function Specs Get interrupt factor register value

CDC_GetHirqReq

9.2

Format:

Uint16 CDC_GetHirqReq

(void)

Input:

none

Output:

none

Function value:

Function:

Gets the interrupt factor register (HIRQREQ) value.

Title

Function

Function Name

[ -- ]

No.

Function Specs Clear interrupt factor register

CDC_ClrHirqReq

9.3

Format:

void CDC_ClrHirqReq

(Uint16 bitpat)

Input:

bitpat : cleared bit pattern (bit to clear is 0, other bits are 1)

Output:

none

Function value:

none

Function:

Clears the interrupt factor by the designated bit pattern.
(Only 0 is written.)

Remarks:

Since the CD communication interface uses the interrupt factor
register CMOK flag, clearing by the application program is
prohibited.

Title

Function

Function Name

[ -- ]

No.

Function Specs Get interrupt mask register value

CDC_GetHirqMsk

9.4

Format:

Uint 16 CDC_GetHirqMsk

(void)

Input:

none

Output:

none

Function value:

Function:

Gets the interrupt mask register (HIRQMSK) value.

SEGA Confidential

Title

Function

Function Name

[ -- ]

No.

Function
Specifications

Set interrupt mask register

CDC_SetHirqMsk

9.5

Format:

void CDC_SetHirqMsk

(Uint 16 bitpat)

Input:

bitpat : mask bit pattern (bit to mask is 0, other bits are 1)

Output:

none

Function value:

none

Function:

Masks interrupt factor by designated bit pattern.

Title

Function

Function Name

[ -- ]

No.

Function
Specifications

Get MPEG register pointer

CDC_GetMpegPtr

9.6

Format:

Uint 16 *CDC_GetMpegPtr

(void)

Input:

none

Output:

none

Function value:

Function:

Gets MPEG register (MPEGRGB) pointer.