Users of the WDM Opcode¶
This is to document users of WDM $XX opcodes / signature bytes.
| Signature | Emulator | Description |
|---|---|---|
| C7 | KEGS | Call to smartport emulation (C and V determine function) |
| FF | GSPlus | Interface with Host FST logic |
| ?? | Michael Guidero | debugging |
Proposed¶
| Signature | Emulator | Description |
|---|---|---|
| $SS $00 | KEGS | Emus would skip the extra BRK after this |
| $EA | KEGS | performs CLV |
| $EA, $00 | KEGS | Returns emulator info |
WDM $EA $00 returns emulator info: a string describing the emulator name is written to the 24-bit address DBANK.ACC, X=size of that buffer. On output, X=size of string written, ACC is emulator version as BCD so $0123 is version 1.23, and Y=feature support, where bit 0 means the $C06C-$C06F timer is available (the kegs 32-bit cycle counter).