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OS_SerialOp 3
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_SerialOp
» OS_SerialOp 3
OS_SerialOp 3
(SWI &57)
| Entry | |
|---|---|
| R0 | 3 |
| R1 | Character to be sent |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Preserved |
| C flag clear if character was sent, or set if character was not sent (ie the buffer was full) | |
Use
The purpose of this call is to send a byte into the serial output buffer.
Notes
This call puts a character in the serial output buffer, and re-enables the transmit interrupt if it had been disabled by RISC OS. If the serial output buffer is full, the call returns immediately with the C flag set.