Can the mup21 take an external clock?
- To: MISC
- Subject: Can the mup21 take an external clock?
- From: e.matejowsky@xxxxxxxxxx (Eddie Matejowsky)
- Date: Tue, 22 Nov 1994 14:41:36 +1000
>Figure on a refresh every 16 us. That would be 64 KHz. The refresh
>instruction occurs only every 4 instructions, for a clock rate of
>256 KHz. However, these refresh rates are enormously conservative.
>I would try 32 KHz as a conveniently available part.
>
I've just had a look in a "farnell" catalog for xtals, they've got .3072 meg
xtals for $20 AUS compared to $1.50 for a watch xtal. Does it really need to
be a xtal? Is there a way to use an rc or external clock? If you can then a
555 (and a
flipflop to square it up) would make a cheap refresh oscillator.
Eddie.M
Edward Matejowsky.
Queensland University of Technology
Centre for Eye Research
email E.MATEJOWSKY@QUT.EDU.AU
Wk +61 7 864 5731 Hm +65 7 2825382
There is nothing permanent except change.