A83: Re: delay routines...HELP!
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A83: Re: delay routines...HELP!
Dan, I recommend you get my tutorials :)...all those are explained.
Later,
James Matthews (matthews@tkb.att.ne.jp)
ICQ: 7413754
http://home.att.ne.jp/gold/tomcat21/index.html
http://library.advanced.org/18242/
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> From: Dan G. <idsoccer@lesbois.com>
> To: ASM 83 Mailing list <assembly-83@lists.ticalc.org>
> Subject: A83: delay routines...HELP!
> Date: Saturday, October 03, 1998 2:41 AM
>
>
> I have been trying for a few weeks to get a good delay rountine to slow
> down my program in places. I studied the code of many games that use
> delays, and I can't figure out what the commands do. If I implement other
> peoples delay code, my calc crashes.I haven't seen them in any tutorials or
> at the TI site. Many of the routines are similar from different programs.
> Here's the code from frogger...
>
> DelayChk:
> push af <<<<what does push do?
> push bc
> ld a,(level) <<<<I understand the speed settings
> cp 1
> jp z,d2500
> cp 2
> jp z,d2000
> cp 3
> jp z,d1500
> cp 4
> jp z,d1000
> jp nz,500
> d2500:
> ld bc,$2500 <<<<what does the $(number) mean?
> jp delayLoop
>
> d2000:
> ld bc,$2000
> jp delayLoop
>
> d1500:
> ld bc,$1500
> jp delayLoop
>
> d1000:
> ld bc,$1000
> jp delayLoop
>
> d500:
> ld bc,$500
> jp delayLoop
>
> delayLoop:
> DEC BC <<<What is DEC
> LD A, B
> OR C <<what is OR C
> JR NZ, delayLoop
> POP BC <<<what is POP
> POP AF
> ret
>
>