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(6/27/95- 002)
NOTE: A reader's comment/correction form is provided with this
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SEGA Confidential


TM
1994 SEGA. All Rights Reserved.
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
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READER CORRECTION/COMMENT SHEET
Chpt.
pg. #
Correction
Corrections:
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If you should come across any incorrect or outdated information while reading through the attached
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Where to send your corrections:
ST-162-062094
System Library User's Guide
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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.
1.
KenKyusha New Japanese-English Dictionary
1974 Edition
2.
Nelson's Japanese-English Character Dictionary
2nd revised version
3.
Microsoft Computer Dictionary
4.
Japanese-English Computer Terms Dictionary
Nichigai Associates
4th version
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(This page is blank in the original Japanese document.)
ii
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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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iv
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
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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".
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System Library User's Guide
21
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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22
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
HO
S
T
CD
B
L
O
C
K
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
23
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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24
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
25
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
address
BCD
binary coded decimal
binary decimal number
bn.bufno
buffer no.
buffer partition number
bufnum
buffer numbers
total number of buffer partitions
CI
coding information
coding information
CN
channel no.
channel number
Ctrl
control
control
dst
destination
copy and move destination
fad
frame address
frame address
fasnum
fad sector numbers
frame address sector numbers
fid
file identifier
file identifier
fln, filtno
filter no.
filter number
FN
file no.
file number
LSB
least significant bit
least significant bit
MSB
most significant bit
most significant bit
ply
play parameter
play parameters
pos
position parameter
position parameters
SM
submode
submode
sct
sector
sector
ses
session information
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
CD status information
subh
subheader condition
subheader condition for filter
TNO
track no.
track number (music number)
toc
TOC information
TOC information
txwnum
transfer word numbers
(data transfer size in word units)
X, idx
index
index number
word
word
units 2 bytes (16 bits) in length
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26
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
00
Data
01
Data
02
Audio
03
Lead Out
Area
Audio
AA
01
00
2 sec.
00
2 sec.
01
01~
TOC Information
FAD=0 Track start FAD
Track start FAD
01
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.
2 sec.
2 sec.
Session 3
Session 2
Session 1
00
01
02
03 AA 00
04
05
06
AA 00
AA
07
08
09
Figure 2.2 Multi Session Layout
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System Library User's Guide
27
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
R
MPEG Register (RGB data)
CDC_GetMpegPtr
Register Name
R/W
15
14
13
12
11
10
9
8
DATATRNS
R/W
7
6
5
4
3
2
1
0
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28
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.
(c) Names the command end flag of each bit ESEL, EHST, ECPY, EFLS.
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)
Register Name
R/W
15
14
13
12
11
10
9
8
HIRQREQ
R/W
--
--
SCDQ
EFLS
ECPY
7
6
5
4
3
2
1
0
EHST
ESEL
DCHG
PEND
BFUL
CSCT
DRDY
CMOK
Register Name
R/W
15
14
13
12
11
10
9
8
HIRQMSK
R/W
--
--
SCDQ
EFLS
ECPY
7
6
5
4
3
2
1
0
EHST
ESEL
DCHG
PEND
BFUL
CSCT
DRDY
CMOK
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System Library User's Guide
29
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.
Register Name
R/W
15
14
13
12
11
10
9
8
MPEGRGB
R
7
6
5
4
3
2
1
0
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30
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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31
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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32
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
33
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
<STANDBY>
Drive stop status
<PLAY>
CD play in progress
<SEEK>
Seeking
<SCAN>
Scanning
<OPEN>
Tray is open
<NODISC>
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
No
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
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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
No
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.
<STANDBY>
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36
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.
(c) Commands in the <OPEN> status (except for tray open) change to each
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>
<STANDBY>
<SCAN>
<PAUSE>
<STANDBY>
<PAUSE>
<OPEN>
<PLAY>
<SEEK>
<PAUSE>
<STANDBY>
<SCAN>
<STANDBY>
--
<PAUSE>
<OPEN>
<PLAY>
<SEEK>
<PAUSE>
<STANDBY>
<SCAN>
<PLAY>
<PAUSE>
<PAUSE>
<OPEN>
<PLAY>
<SEEK>
<PAUSE>
<STANDBY>
<SCAN>
<SEEK>
<PAUSE>
<PAUSE>
<OPEN>
<PLAY>
<SEEK>
<PAUSE>
<STANDBY>
<SCAN>
<SCAN>
<PAUSE>
<PAUSE>
<OPEN>
<PLAY>
<SEEK>
<PAUSE>
<STANDBY>
<SCAN>
<OPEN>
--
<PAUSE>
<OPEN>
<PLAY>
<SEEK>
<PAUSE>
<STANDBY>
<SCAN>
<NODISC>
--
<OPEN>
<OPEN>
<OPEN> <OPEN>
<OPEN>
<OPEN>
<OPEN>
<RETRY>
changes
<PAUSE>
<OPEN>
<PLAY>
<SEEK>
<PAUSE>
<STANDBY>
<SCAN>
<ERROR>
--
<PAUSE>
<OPEN>
<PLAY>
<SEEK>
<PAUSE>
<STANDBY>
<SCAN>
<FATAL>
--
undefined
undefined
undefined
undefined
undefined
undefined
undefine
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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
39
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
0
SCDQ Flag
Pack Data Aquisition
(Subcode R
~
W)
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
Get
Put
Write
Read
Read
Write
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
Register
VDP2
Figure 5.1 CD Block Entire Data Flow
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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
Yes
Yes
No
No
No
Stream
Clear
Figure 5.4 Type of Stream Select Process
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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
2
1
0
N
1
-1
2
1
0
N
p
-1
2
1
0
N
23
-1
2
1
0
Sector postion
Last partition
First partition
Buffer partition size (sector units) Np
1
P
2 3
Buffer partition number
0
Np: buffer partition size, P: buffer partition number,
Np
CD buffer size
23
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
B
A or B
Figure 5.7 Selector Connection by OR Conditions
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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
O
X
X
True Output
X
X
False Output
O
X
X
Partition Output
O
X
O
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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.
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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.
(c) Storing user data within a buffer partition, except data from a CD device, is
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
User Data
EDC/ECC
EDC,
etc.
Header
Header
Header
Sub
header
Sub
header
Sector
synch
Sector
synch
Sector
synch
12
4
2048
288 bytes
12
4
2048
280 bytes
8
12
4
2324
4 bytes
8
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
FN
CN
SM
CI
FN
CN
SM
CI
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.
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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.
f1
f2
f3
f3
f1
f2
Root directory
Sub directory
Root directory
Self
Parent=Self
Sub directory
Parent
Sub directory
Sub directory
Parent
Directory code
Directory block
(Directory file)
File
Pass table
Volume Identifier
1
2
3
~
~
n
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
2
1
0
~
~
~
~
Self
Parent
~
~
~
~
2
1
0
File Information Table
Move directory
(Hold file information in directory move destination)
2
1
0
3
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)
i
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)
<on the CD-ROM>
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
(c) Filter and connected buffer partition
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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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
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
No
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
0
Indicates that logic value is false
TRUE
1
Indicates that logic value is true
OFF
0
Indicates switch is off (false)
ON
1
Indicates switch is on (true)
3) Additional
Constant Name
V a l u e
Description
NULL
((void *)0)
NULL pointer
56
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
SP
2
1
0
Buffer Partitions
CDC_SNUM_END
CDC_SPOS_END
Designated Sector Location SP
Stream
Filter
3) Other
Title
Data
Data Name
No
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
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7.2.3
TOC and Session Information
1) TOC Information
Track 1 Information
0
1
2
n
98
99
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
2
3
<Track Location Information>
Track start frame address
byte 0
1
Ctrl Adr
Tracks not existing on TOC is FFFFFFFFH
2
3
<Read Out Information>
Read out start frame address
0
1
Ctrl Adr
Indicates final session value for multi sessions
2
3
0
1
Ctrl Adr
Ctrl Adr
<First/Last Track Information>
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
0
1
2
3
byte
0
1
2
3
<Total Session Information>
<Session Location Information>
Total Session Information
Session 1 Information
Session 2 Information
Session 98 Information
Session 99 Information
Session n Information
4 Bytes
0
1
2
n
98
99
~
~
~
~
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
No
Data Specification
TOC and Session Information
3.0
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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
X
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
No
Data Specification
Status and Report (1/2)
4.0
Value
Status
Explanation
00H
<BUSY>
Status currently changing
01H
<PAUSE>
Currently paused
02H
<STANDBY>
Standby (drive in suspended
status)
03H
<PLAY>
Playing CD
04H
<SEEK>
Seeking
05H
<SCAN>
Scanning
06H
<OPEN>
Tray is opened
07H
<NODISC>
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)
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3) CD Report
FAD
Flg
Rep
Cnt
Ctrl
Adr
TNO
X
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)
X
: 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
No
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 / FFH
O / FFH
O / FFH
O / FFFFFFH
<PAUSE>
O
O
O
O
O
<STANDBY>
value at pause
value at pause
value at pause
value at pause
value at pause
(when seek home)
FFH
FFH
FFH
FFH
FFFFFFH
<PLAY>
O
O
O
O
O
<SEEK>
O
target position
target position
target position
target position
<SCAN>
O
O
O
O
O
<OPEN>
FFH
FFH
FFH
FFH
FFFFFFH
<NODISC>
FFH
FFH
FFH
FFH
FFFFFFH
<RETRY>
O
O
O
O
O
<ERROR>
FFH
FFH
FFH
FFH
FFFFFFH
<FATAL>
undefined
undefined
undefined
undefined
undefined
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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>.
(c) The value immediately before <ERROR> is retained. If changing to the
<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.
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7.2.5
Subcode Information
1) Subcode Q Information
(a) When Adr = 1
Ctrl
Adr
TNO
X
byte 1 2 3 4 5 6 7 8 9 10
00
CRC
P_FAD
Q_FAD
Ctrl Adr : CONTROL/ADR byte
TNO
: Track No. (binary value not BCD)
X
: 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
Pack
Pack
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
24 bytes
24 bytes
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
No
Data Specification
Subcode Information
5.0
TNO
X
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
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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
No
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
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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
No
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
No
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
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Title
Data
Data Name
No
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
65
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;
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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
No
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)
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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
No
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
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2) Play Parameters
CdcPly *ply
68
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)
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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
1
Track designation
tno 1, x1
tno 2, x2
2
Frame address
designation
fad
fasnum
note: 1
3
Play from first of disc
CDC_PTYPE_DFL
tno 2, x2
fasnum
4
Play until end of disc
tno 1, x1
fad
CDC_PTYPE_DFL
5
End position does not
change. (only the start
position changes)
tno 1, x1
fad
CDC_PTYPE_NOCHG
note: 2
6
Start position does not
change. (only the end
position changes)
CDC_PTYPE_NOCHG
tno 2, x2
fasnum
note: 2
7
Play is retried from the
current position without
changing the play range
and play mode.
CDC_PTYPE_NOCHG
CDC_PTYPE_NOCHG
CDC_PM_NOC
HG is
designated
in
the Play mode.
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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
No
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
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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)
RT
(Real Time Sector)
EOF (End
Of
File)
1: Record end sector
1: Video
sector
1: Audio
sector
1: Data
sector
1: Trigger
ON
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
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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
6
5
4
3
2
1
0
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
No
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
No
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
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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]
No
Function Specification CD Play
CDC_CdPlay
2.1
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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
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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
Register Access
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)
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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:
hw
: 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:
C
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
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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
6
5
4
3
2
1
0
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
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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
6
5
4
3
2
1
0
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
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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)
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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
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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
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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:
1.
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
*/
2.
Track/Index Designation
CDC_POS_PTYPE (&pos)
=
CDC_PTYPE_TNO;
CDC_POS_TNO (&pos)
=
tno;
/* track number
*/
CDC_POS_IDX (&pos);
=
x;
/* index number
*/
3.
CD Play Stop (Default vlaue designation: Seek home position)...... Stop
CDC_POS_PTYPE (&pos) = CDC_PTYPE_DFL;
4.
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
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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)
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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
6
5
4
3
2
1
0
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
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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
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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
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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
6
5
4
3
2
1
0
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
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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
6
5
4
3
2
1
0
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
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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
6
5
4
3
2
1
0
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
bn
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
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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
0
: Buffer partition number is ignored
1) Reset Flag
bit 7
6
5
4
3
2
1
0
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
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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
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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
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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
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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
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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
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98
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
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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.
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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.
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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:
Register pointer
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:
Register 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:
register value
Function:
Gets the interrupt mask register (HIRQMSK) value.
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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:
register pointer
Function:
Gets MPEG register (MPEGRGB) pointer.