VDU 20

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Restores the default colours and palette.

VDU 20
Syntax VDU 20
Keyboard equivalent CTRL T
Character stream (hex) 14
Description Reprograms the palette to the default for the current MODE.
Resets the current text and graphics colours to the defaults.
Resets the graphics paint modes to the defaults.

Description

VDU 20 resets the colour scheme to the one that was set up when the current screen MODE was selected.

It has no effect in MODE 7 which is a Teletext mode. In the other modes, the logical colours of items already on screen are not affected by VDU 20.

  • The palette is set to the default, according to the number of colours in the current MODE (see the tables below). The set of actual colours on screen instantly changes to the default set.
  • The text foreground colour is set to the logical colour for white. Text printed after VDU 20 will appear in this colour.
  • The text background colour is set to the logical colour for black.
  • The graphics foreground colour is set to the logical colour for white, and the foreground paint mode is set to 'overwrite'.
  • The graphics background colour is set to the logical colour for black, and the background paint mode is set to 'overwrite'.

Default palettes

Default palette for two-colour MODEs
Logical colour Actual colour
0 Black
1 White


Default palette for four-colour MODEs
Logical colour Actual colour
0 Black
1 Red
2 Yellow
3 White


Default palette for sixteen-colour MODEs
Logical colour Actual colour
0 Black
1 Red
2 Green
3 Yellow
4 Blue
5 Magenta
6 Cyan
7 White
8 Flashing black/white
9 Flashing red/cyan
10 Flashing green/magenta
11 Flashing yellow/blue
12 Flashing blue/yellow
13 Flashing magenta/green
14 Flashing cyan/red
15 Flashing white/black

-- beardo 21:58, 10 November 2007 (UTC)