[A83] Re: LCDBusy
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[A83] Re: LCDBusy
> Van: Robert Maresh <gardenerbm@netzero.net>
>
> Why do we use this routine: (33 clocks)
>
> [deletia]
>
> When we could use this one: (32, could change it to be 33?)
>
> LCD_BUSY:
> halt \ halt \ halt \ halt \ halt \ halt \ halt \ halt
> ret
>
> Sure, it's four bytes larger, but I thought halt saves on battery life.
> Is this one of TI's oversights, or am I completely wrong???
>
> Bob Maresh
Much better than doing a call to _lcdbusy/lcdbusy:
ex (sp),hl ; 19 clocks ; 1 byte
ex (sp),hl ; 19 clocks ; 1 byte
(that makes: 38 clocks and 2 bytes, anough clocks and 1 byte smaller)
Okay, you can't use this if you make an interupt which is "fed" by pushing
things on the stack, but if you can make such things, you won't need
listening to me anyways... (Don't think that stack-idea is very useable,
but well... you need to know the exeptions)
Henk Poley