OSBYTE &03

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OSBYTE &03 (3) - Select output device

On entry, X=new output selection

On exit, X=old output selection

Controls which output device or devices receive the characters sent to OSWRCH.

The value of X is made up as follows:

Bit Meaning if set
0 Enable serial port
1 Disable screen drivers (overrides VDU 2 and VDU 6)
2 Disable printer (overrides VDU 2 and bits 3 and 6)
3 Enable printer (overrides VDU 3)
4 Disable output to *SPOOL file
5 Not used
6 Disable printer except for VDU 1 sequences (overrides bit 3)
7 Not used

This flowchart shows the flow of characters from the OSWRCH entry point to the output devices. Flowchart of pathways from the OSWRCH entry point to the output devices


Common OSBYTE 3 settings are:

*FX3,0 normal state, serial disabled, VDU enabled, printer enabled by VDU 2, spool output if *SPOOL file open
*FX3,1 normal output, also send to serial port
*FX3,2 disable all output except printer port and any *SPOOL file
*FX3,3 disable VDU, enable serial port and any *SPOOL file
*FX3,16 normal output without copying to *SPOOL file
*FX3,18 disable all output except printer port
*FX3,23 disable all output except serial port
*FX3,86 disable all output entirely

-- beardo 21:43, 5 October 2007 (BST) Jgharston (talk) 01:42, 25 December 2016 (UTC)