VDU 0

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The null character.

VDU 0
Syntax VDU 0
Keyboard equivalent CTRL @
Character stream (hex) 00
Description Does nothing.

Description

VDU 0 prints the ASCII character NUL. NUL does nothing. It is usually used to complete a VDU sequence that has been created intentionally or accidentally.

When the display drivers are in an unknown state, they can be reset by printing nine NULs. This is guaranteed to fill any outstanding queue, and any excess NULs are harmless. In BASIC V, the VDU n| syntax sends these NULs conveniently.

-- beardo 00:03, 25 September 2007 (BST)