Z80 Routines:Input:DetectKeyPress

From WikiTI
Revision as of 05:47, 21 April 2010 by Galandros (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search


This routines tells whether any keys at all are pressed. Returns the result in z flag.

;out: z flag for no key, nz flag for any key pressed (except On)
detectkeypress:
	xor a
	out (1),a	; any part of keyboard is detected
	nop
	nop
	in a,(1)
	inc a
	ret