The Rom based parts are available from the factory with your program in it.
You can not program them in the field. They make sense if your code is
solid and you have high volume to reap the savings. There is an NRE
associated so the need for a high volume to save money is there. I have a
couple of clients that have Rom based 54 designs in high volume and have
saved a lot of money but if a problem is found they panic because they
would need to eat the chips made so far if a program change is needed.


At 07:46 PM 12/14/97 +0100, you wrote:
> What's the difference between Microchip xxCxx and xxCRxx parts?
>
> AFAIK CR version is ROM based and C version is EPROM based...
>
> but.. what exactly does it mean?? I need a different programmer??
>--
>
>   - *Alex* -
>
>      (azummo@ita.flashnet.it)
>
>
Larry G. Nelson Sr.
mailto:L.Nelson@ieee.org
http://www.ultranet.com/~nr