Re: A86: Re: question
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Re: A86: Re: question
actually, it would make sense to have them both always be the same... if you
think about the entire purpose of the register in the first place is to
dynamically refresh the ram so that it doesn't go bad... but, there are only
$8000 bytes of ram, so the 7th bit need not ever change (although it would make
more sense if it was always 1, unless the refresher just ignored it and made it 1
regardless). Also, b/c it can read/write a word at a time to/from ram, the 0th
bit can stay constant as well...
also, what does iirc mean?
Jimmy Mårdell wrote:
> At 02:14 1998-03-08 -0500, you wrote:
> >
> >a nice way to get random numbers that ppl can't tamper with, and that doesn't
> >require the OP registers is the 'r' register (which i believe is what
> ztetris,
> >or at least one of the zshell versions, if not jimmy mardell's, uses)...
> >something like this is good:
> > ld a,r
> > shr a
> >
> >the shr a is necessary b/c the r register increases by 2 each clock cycle, so
> >the right bit is always the same. now a is a 7 bit random #... if you need
> >less bits, then shift it right some more... also, you can't really use that
> >method again until you do something that requires some sort of user input
> >because it will always be so much above the original, anyway, i'm
> babbling, so
> >i'll stop now... hope this helps.
>
> Are you sure about that? I checked the R register once, and IIRC, it's
> bit 7 that's always cleared, not bit 0 (which I though at first). And
> the R register is, iirc, increased with 1, except that bit 7 is always 0.
>
> --
> Real name: Jimmy Mårdell
> IRC......: Yarin
> Email....: mailto:yarin@acc.umu.se <-- NEW E-MAIL ADDRESS!!!!
> Homepage.: http://www.algonet.se/~mja/
--
Stephen Hicks
mailto:shicks@mindspring.com
UIN:5453914
AIM:Kupopo1
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