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OS_Byte 129 (scan single)
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_Byte
» OS_Byte 129
» OS_Byte 129 (scan keyboard for single key)
OS_Byte 129 (scan keyboard for single key)
(SWI &06)
| Entry | |
|---|---|
| R0 | 129 (&81) |
| R1 | &80 – &FF lowest keyboard scan code EOR &FF |
| R2 | &FF |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | 0 if not pressed, or 255 if pressed |
| R2 | 0 if not pressed, or 255 if pressed |
Use
The purpose of this call is to scan the keyboard for a range of keys.