Lawrence Glaister wrote:

> I have a data sheet for the TI and national versions of the chip, but I have
> been unable to locate the programming requirements for these extinct ttl
> proms. Does anyone know of a programming cct, software or description of the
> programming sequence? I need to update an old radio that used these for
> configuration and frequency selection.

I have the NATIONAL PROM programming procedure.
BUT...
This is the PIC list!
Use a small PIC to simulate the 4 bit X 256 PROM and get all kinds of
advantages!

>
> cheers
> =======================================================
> Lawrence Glaister VE7IT             email: lg@jfm.bc.ca
> 1462 Madrona Drive                    http://jfm.bc.ca/
> Nanoose Bay BC Canada      http://gspy.sourceforge.net/
> V9P 9C9               http://members.home.net/cncstuff/
> =======================================================
>
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--
  *
  |  __O    Thomas C. Sefranek   tcs@cmcorp.com
  |_-\<,_   Amateur Radio Operator: WA1RHP
  (*)/ (*)  Bicycle mobile on 145.41, 448.625 MHz

http://hamradio.cmcorp.com/inventory/Inventory.html
http://www.harvardrepeater.org

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