| OSByte call | Action | Available on: | |||
|---|---|---|---|---|---|
| (dec) | (hex) | BBC | Master | Electron | |
| 3 | 03 | Select output stream | x | x | x |
Entry parameters
| X | The output device(s) |
|---|
On exit:
| X | Old value |
|---|
This call selects the output streams to be used. The X register contains the streams to use, one per bit:
| Bit | Output selected if bit is set |
|---|---|
| 0 | Enables RS423 driver |
| 1 | Disabled VDU driver |
| 2 | Disabled printer driver |
| 3 | Enables printer, independent on CTRL B/C or VDU 2,3 |
| 4 | Disables spooled output |
| 5 | Not used |
| 6 | Disables printer driver unless char is preceded by VDU 1 |
| 7 | Not used |
*FX 3,0 selects the default output:
- RS423 disabled
- VDU enabled
- Printer enabled if selected by VDU 2
- Spooled output enabled if selected by *SPOOL
Econet
Bit 3 should not be used to enable the printer as it might conflict with Econet claiming the printer.
Electron
If RS423 or printer output is selected on the Electron a paged ROM service call is issued. If no suitable response is received the output is thrown away.