Read Sub-Channel
- 105 -
2.27
Read Sub-Channel (42h)
Operation Code is (42h).
MSF
If “1”, the CD-ROM address field of the returned sub-channel data is in MSF format. The
returned M,S and F fields are specified in hex. If “0”, the CD-ROM address field of the
returned sub-channel data is in logical address format.
Sub Q
The Sub Q bit set to one requests the target return the Q sub-Channel data. Set to zero
requests that no sub-channel data will be returned.
Sub Channel Data Format
The Sub Channel Data Format Field specifies the returned Sub Channel Data. The format
codes are listed below.
Track Number
The track number field specifies the track number from which the ISRC Code is
transferred. This field must have the value between 01h and 63h (99 bcd), and is valid only
when the Sub Channel Data Format field is 03h. In this case, the target returns the ISRC
Code of the track if it is detected. In other cases (i.e. Sub Channel Data Format Field not
equal to 03h), the drive will return Check Condition status if the Track Number Field is not
equal to 00h. The sense key and additional sense code are set to ILLEGAL
REQUEST/INVALID FIELD in CDB.
Allocation Length
The READ SUB-CHANNEL command requests that the target return the requested sub-channel
data of the current block plus the status of an audio play operation.
Format Code
Sub-Channel Data Block
00h
:
Q Sub-code Data
01h
:
CD-ROM Current Position
02h
:
Media Catalog Number (UPC/Bar Code)
03h
:
Track International Standard Recording Code (ISRC)
04h-FFh
:
Reserved
The returned sub-channel data consists of a four-byte header followed by a sub-channel data
block. The header contains the audio status byte and the sub-channel data length field. If the
Sub-Q bit in byte 2 of the CDB is zero, the target will not return the sub-channel data block. In
this case the sub-channel data length is 0.
Содержание DR-706S
Страница 2: ...CD ROM SCSI 2 Command Set R e f e r e n c e M a n u a l V e r s i o n 3 1 OB U0077C ...
Страница 36: ...Inquiry 23 this page has been left intentionally blank ...
Страница 71: ...CD ROM SCSI 2 COMMAND REFERENCE MANUAL VERSION 3 1 OB U0077C 58 this page has been left intentionally blank ...
Страница 106: ...Read CD ROM Capacity 93 this page has been left intentionally blank ...
Страница 124: ...Read Sub Channel 111 this page has been left intentionally blank ...
Страница 130: ...Read TOC 117 this page has been left intentionally blank ...
Страница 140: ...Request Sense 127 this page has been left intentionally blank ...
Страница 158: ...Stop Play Scan 145 2 40 Stop Play Scan 4Eh The STOP PLAY SCAN CD ROM Command stops playback of CD ROM audio commands ...
Страница 164: ...Verify 12 151 2 43 Verify 12 AFh Operation code is AFh See VERIFY 10 for complete description of this command ...
Страница 172: ...Read CD DA 159 this page has been left intentionally blank ...