VDU 22

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Selects a display MODE.

VDU 22
Syntax VDU 22,<numeric>
Character stream (hex) 16 <mode>
Description Changes the display to MODE <mode>

Description

VDU 22,n changes the display to MODE n. For a list of display modes, see MODE.

Since the display memory may 'explode' without the current language being informed, VDU 22,n can corrupt user memory in the I/O processor. Mode changes must therefore be made through the language (for instance in BASIC, by the statement MODE n.)

When user memory is separate from display memory (that is, when *SHADOW mode, a Tube coprocessor or the Archimedes is in use) then mode changes can be made by either method.

The start of display memory for a given MODE can be found without changing to that MODE, with OSBYTE &85.

Screen display MODEs

MODE 0 | MODE 1 | MODE 2 | MODE 3 | MODE 4 | MODE 5 | MODE 6 | MODE 7
MODE 8 | MODE 9 | MODE 10 | MODE 11 | MODE 12 | MODE 13 | MODE 14
MODE &60 | MODE &61 | MODE &62 | MODE &63 | MODE &64 | MODE &65 | MODE &66 | MODE &67
MODE &68 | MODE &69 | MODE &6A | MODE &6B | MODE &6C | MODE &6D | MODE &6E | MODE &6F
MODE | VDU 22

beardo 20:52, 10 November 2007 (UTC)