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Re: 64/65 Cycle Rule?

Subject: Re: 64/65 Cycle Rule?
From: Eric Smith <eric-no-spam-for-me@brouhaha.com>
Date: 25 Aug 2003 02:28:03 -0700
Newsgroups: comp.sys.apple2
Organization: Eric Conspiracy Secret Labs
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"Bryan Parkoff" <spam> writes:
>     Are you saying that half 6502 cycle access to RAM and another half 6502
> cycle access to Video Circuitry?

Yes.

> It is why Video must update 560x192 pixels
> every 6502 cycle.  Correct?

No.  During every 6502 cycle, one byte of display RAM is read by the
video circuitry.  (Two bytes on a //e with an 80 column card or 128K
memory expansion card.)  At most that is 14 pixels displayed per 6502
cycle.

References:
- 64/65 Cycle Rule?
  - From: "Bryan Parkoff" <spam>
- Re: 64/65 Cycle Rule?
  - From: Eric Smith <eric-no-spam-for-me@brouhaha.com>
- Re: 64/65 Cycle Rule?
  - From: "Bryan Parkoff" <spam>

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