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OS_Byte 129 (time)
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_Byte
» OS_Byte 129
» OS_Byte 129 (read a key within time limit)
OS_Byte 129 (read a key within time limit)
(SWI &06)
| Entry | |
|---|---|
| R0 | 129 (&81) |
| R1 | 0-255 (time limit low byte) |
| R2 | &00 – &7F (time limit high byte) |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | ASCII code of character read, undefined if not read |
| R2 | 0 character read |
| 27 escape condition | |
| 255 timeout |
Use
The purpose of this call is to read a key within a specified time limit.
Notes
This call will extract a character from the keyboard buffer/current function key expansion if one is available, else will wait for (R2 * 256 + R1) centiseconds, where the maximum wait is 327.67 seconds, as R2 <= 127.
Cursor edit mode will operate if enabled with OS_Byte 4.
If an escape condition is detected the application should either acknowledge it with OS_Byte 126 or clear it with OS_Byte 124.