Re: HC logic with 6502+rigging up a crystal

[nathan@visi.com (Nathan Mates)]

In article <515o1r$4p4@totara.its.vuw.ac.nz>,
Rob Thomson  <rob.thomson@vuw.ac.nz> wrote:
>Can I use a NMOS 6502 or 6522 happily with 74HC CMOS logic?

   Should be able to do so pretty easily. The Apple I and II had a
heck of a lot of 74xxs onboard. (Wish I had a schematic or motherboard
handy so I could count for myself.)

>Also, what is the best way to get from up a 4Mhz crystal to two
>opposite 1Mhz signals. eg. what capacitors, resistors and logic
>(latches or counters?) would I need to do this and how.

   There should be some divide-by-2 or divide-by-4 counters in the
74xx series (so says the computer science major, not the electrical
engineer). Or, a set of flip-flips connected up correctly should
probably do it. Once you get down to 1Mhz, then an inverter (I KNOW
there's a 74xx for that :) will deal with that fine.

Nathan Mates
--
<*> Nathan Mates http://www.visi.com/~nathan/      <*>
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