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OS_Byte 128
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_Byte
» OS_Byte 128
OS_Byte 128
(SWI &06)
| Entry | |
|---|---|
| R0 | 128 (&80) |
| R1 | Reason code |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Bits 0-7 give LSB of answer |
| R2 | Bits 0-23 give bits 8-31 of answer |
Use
The purpose of this call is to return the mouse coordinates, or number of bytes in an input buffer, or number of free bytes in an output buffer.
Notes
This call checks the (buffered) mouse position or the free space in system buffers, depending on the reason code passed in R1. It is recommended to use OS_Mouse to read the mouse position, as this reads the current (unbuffered) position.