OSBYTE &7A

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OSBYTE &7A (122) - Keyboard Scan from &10

   Simply performs OSByte &79 with X=16

Usage note

On exit Y is undefined, and typically contains an invalid keynumber.[1] Paged ROMs that handle service call &03 commonly, though incorrectly, pass Y unchanged to OSBYTE &78 where it selects an undefined key as the second active rollover key. This does not cause a spurious keypress in practice.

See Also

References

  1. Stardot forum post by Tom Seddon, 11th December 2024.

Jgharston 21:17, 26 May 2009 (UTC)