Re: A92: Re: keyb matrix

To: assembly-92@lists.ticalc.org
Subject: Re: A92: Re: keyb matrix
From: "David Kühling" <dkuehlin@hell1og.be.schule.de>
Date: Mon, 28 Sep 1998 11:43:23 +0100
Delivered-To: assembly-92-outgoing@towerguard.unix.edu.sollentuna.se
References: <01bdea46$42f673e0$LocalHost@lukas1>
Reply-To: assembly-92@lists.ticalc.org


Klaus wrote:
> 
> ...
> Getkey:
> movem.l d0-d1/a0,-(a7)
> lea keystat(pc),a0
> move.w #$FFFE,d0
> move.w #9,d1
> GetKeys:
> move.w d0,$600018
> nop
> nop
> nop
> nop
> nop
> nop
> nop
> nop
> nop
> move.b $60001B,(a0)+
> rol.w #1,d0
> dbra.w d1,GetKeys
> movem.l (a7)+,d0-d1/a0
> rts
> 

Use
	move.l (a7),(a7)
	move.l (a7),(a7)
	move.l (a7),(a7)
instead of the NOPs. It's a little bit smaller, since the move-
instructions take more time. 
Redirection could be done by more effectively by making all
vectors point to the _same_ rte. (everything else would be 
memory wasting). Instead of redirecting all those ints, you
could just switch them off by:

	move.w	#$700,d0
	trap	#1		; switch off interrupts, old state: d0
	
	...			;(don't change d0!)

	trap	#1		; restore interrupts

References:

A92: Re: keyb matrix

From: "Klaus" <lukas1@xpoint.at>

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