Parallel_Op 2 (changes)
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ParallelDeviceDriver
» SWI Calls
» Parallel_Op
» Parallel_Op 2
Parallel_Op 2
(SWI &42EC1)
| Entry | |
|---|---|
| R0 | 2 (Reason code) |
| R1 | EOR mask |
| R2 | AND mask |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Old contents of register |
| R2 | New contents of register |
Status Register Contents
| Bit | Meaning | Port | Pin |
|---|---|---|---|
| 0 | Not Strobe | 1 | |
| 1 | Not Autofeed | 14 | |
| 2 | Init | 16 | |
| 3 | Not SelectIn | 17 | |
| 4 | IRQ enable | ||
| 5 | Direction | ||
| 6 | Reserved | ||
| 7 | Reserved |
Use
The purpose of this call is to read/write the parallel control register.
Notes
This SWI writes or reads the the control register sent to the printer port.
See also
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