Read TOC

2.28Read TOC (43h)

Operation Code is (43h).

The READ TOC command requests the target transfers data from the table of contents to the initiator.

This command has been modified from the SCSI-2 READ TOC command with the addition of the Format field to support multi-session discs.

Format field

Definition

00b

Same as SCSI-2. The Start Track Field specifies the starting track number

 

for which the data will be returned. For multi-session discs, this command

 

will return the TOC data for all sessions.

01b

This format returns the first session number, last session number and the

 

starting address of the last session. The Start Track field is reserved and

 

should be set to zero.

10b

All Sub-Channel Q code information.(DRM-602X only)

11b

Reserved.

The Start Track field specifies the starting track number for which the data shall be returned. If this value is zero, the table of contents data shall begin with the first track on the medium. The data is returned in contiguous ascending track number order.

If the Start Track field is not valid for the currently installed medium, the command shall be terminated with Check Condition status. The sense key shall be set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.

IMPLEMENTORS NOTE: The maximum TOC data length possible on currently available CD- ROM media is 804 bytes, or 100 TOC track descriptors.

The TOC data block contains a four byte header followed by zero or more TOC track descriptors.

The TOC data length specifies the length in bytes of the following TOC data that is available to be transferred during the DATA IN phase. The TOC data length value does not include the TOC data length field itself.

The first track number field indicates the first track number in the table of contents. The last track number field indicates the last track number in the table of contents before the lead-out track number.

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