| Entry | |
|---|---|
| R0 | Reason code |
| All other registers dependent on reason code | |
| Exit | |
|---|---|
| R0 | Preserved |
| All other registers dependent on reason code | |
The purpose of this call is to provide a number of general operations.
The action performed depends on the reason code value in R0.
| # | Hex # | Action |
|---|---|---|
| 0 | &00 | Read line from input stream |
| 1 | &01 | Read system clock |
| 2 | &02 | Write system clock |
| 3 | &03 | Read interval timer |
| 4 | &04 | Write interval timer |
| 9 | &09 | Read pixel logical colour |
| 10 | &0A | Read a character definition |
| 11 | &0B | Read palette |
| 12 | &0C | Write palette |
| 13 | &0D | Read current and last graphics cursors |
| 14 | &0E | Read CMOS clock |
| 15 | &0F | Write CMOS clock |
| 21 | &15 | Define pointer and mouse parameters |
| 22 | &16 | Write screen base address |