Difference between revisions of "OSWORD &FE"
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On entry: | On entry: | ||
| − | XY?0 | + | XY?0 = &10 (send block length) |
| − | XY?1 | + | XY?1 = &03 (receive block length) |
| − | XY! | + | The rest of the block is a SCSI command block as per OSWORD &72 |
| + | XY?2 = returned result, 0=ok | ||
| + | XY!3 = data address | ||
| + | XY?7 = command | ||
| + | XY?8 = drive number in b5-b7, sector b16-b20 in b0-b4 | ||
| + | XY?9 = sector number b8-b15 | ||
| + | XY?10 = sector number b0-b7 | ||
| + | XY?11 = number of sectors or 0 | ||
| + | XY?12 = 0 | ||
| + | XY!13 = data length if X%?9=0 | ||
| − | This is loaded by the Z80 Tube v2 client code from $.CPM.X or $.CPM.Y | + | This is loaded by the Z80 Tube v2 client code from $.CPM.X (for BBC B/B+) or $.CPM.Y |
| − | on the host filing system. The code is currently being disassembled. | + | (for Master) on the host filing system. The only commands supported are &08 (Read), |
| + | &0A (Write) and &0B (Seek/Park). | ||
| + | |||
| + | * The disk layout accessed is 10 sectors per track. | ||
| + | * There are some tests of the byte passed at XY?12. | ||
| + | * The default code fails if called from the I/O processor with the control block at &xxFE or &xxFF due to incrementing X without carrying the overflow into Y. | ||
| + | |||
| + | The code is currently being disassembled. | ||
==OSWORD &FE (254) - DOS Text output (80x86 DOS, unimplemented)== | ==OSWORD &FE (254) - DOS Text output (80x86 DOS, unimplemented)== | ||
Revision as of 12:09, 9 December 2024
OSWORD &FE (254) - Z80 MFM disk access (Z80 Tube OS)
On entry:
XY?0 = &10 (send block length)
XY?1 = &03 (receive block length)
The rest of the block is a SCSI command block as per OSWORD &72
XY?2 = returned result, 0=ok
XY!3 = data address
XY?7 = command
XY?8 = drive number in b5-b7, sector b16-b20 in b0-b4
XY?9 = sector number b8-b15
XY?10 = sector number b0-b7
XY?11 = number of sectors or 0
XY?12 = 0
XY!13 = data length if X%?9=0
This is loaded by the Z80 Tube v2 client code from $.CPM.X (for BBC B/B+) or $.CPM.Y (for Master) on the host filing system. The only commands supported are &08 (Read), &0A (Write) and &0B (Seek/Park).
- The disk layout accessed is 10 sectors per track.
- There are some tests of the byte passed at XY?12.
- The default code fails if called from the I/O processor with the control block at &xxFE or &xxFF due to incrementing X without carrying the overflow into Y.
The code is currently being disassembled.
OSWORD &FE (254) - DOS Text output (80x86 DOS, unimplemented)
The 6502 host support code in 6502.SYS installed by the 80x86 DOS just returns from OSWORD &FE.
See Also
Jgharston 14:29, 26 May 2009 (UTC) Jgharston (talk) 03:29, 20 July 2020 (CEST)
