CD_EnquireTrack (changes)
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CDFSDriver
» SWI Calls
» CD_EnquireTrack
CD_EnquireTrack
(SWI &4124E)
| Entry | |
|---|---|
| R0 | 0 to return track range, or a valid track number |
| R1 | Pointer to 5 byte track block |
| R7 | Pointer to |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Preserved |
| R7 | Preserved |
5 Byte Track Block
If R0 = 0 on entry, the track range is returned in the block as follows:
| Offset | Contents |
|---|---|
| 0 | First track on CD (1-99) |
| 1 | Last track on CD (1-99) |
| 2 – 4 | Corrupted |
If R0 is a valid track number on entry, then information about that track is returned in the block:
| Offset | Contents |
|---|---|
| 0 | Logical block address of track start (ie Mode 0 address) |
| 4 | Audio control bits specifying the type of information the track holds: |
| Bit | Meaning | |
|---|---|---|
| 0 | 0 = audio, 1 = data | |
| 1 | 0 = 4 channel sound, 1 = 2 channel sound | |
| 2-7 | Reserved |
Use
The purpose of this call is to return track range, or info on a specified track.
Notes
Track numbers do not necessarily start at 1.
See also
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