CD_SCSIUserOp (changes)
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CDFSDriver
» SWI Calls
» CD_SCSIUserOp
CD_SCSIUserOp
(SWI &4126B)
| Entry | |
|---|---|
| R0 | Data Transfer (Value of Bits 24 – 25) |
| R1 | Length of |
| R2 | → |
| R3 | → buffer for data transfer |
| R4 | Length of transfer |
| R5 | Timeout in centi-seconds (0 = default) |
| R7 | Pointer to |
| Exit | |
|---|---|
| R3 | Updated |
| R4 | Updated |
| R5 | Preserved |
| R6 | Preserved |
| R7 | Preserved |
| R8 | Preserved |
| R9 | Preserved |
Flags
NZC = corrupted
If V set R0-R2 are as for SWI SCSI_Op?
or R0 → error not in SCSI range and R1,R2 corrupt
else R0-R2 = preserved
Data Transfer Values
| Bit Value | Meaning |
|---|---|
| 0 | No transfer |
| 1 | Read |
| 2 | Write |
| 3 | Reserved |
Use
When you want to issue a SCSI command to a drive, you should use this call, rather than SCSI_Op?. This will ensure that drives which aren’t part of the SCSI stack (e.g. ATAPI drives) will receive the command.
Notes
CD_SCSIUserOp must not be called in the background (for compatibility with ATAPI drives).
See also
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