On Wed, 12 Apr 2000 00:14:53 -0700, you wrote:

>   Tony, I've not used the 16F873/874 devices but I have used the
>16F876/877. According to the data book (DS30292A), the upper 16 Bytes are
>aliased to 70h-7Fh in the 876/877 and are separate in the 873/874. This
>provides compatibility with the 73/74 and 76/77 devices. Hopefully
>someone else has F873/874 devices to verify this but I think this is the
>case. But with Microchip's data books, `Lord only knows'...
>
>   - Tom
>
>At 09:38 AM 4/12/00 +1000, Tony Nixon wrote:
>>Can anyone verify that the 16F873/4 RAM at 70h - 7Fh is not the same in
>>each page as in the 16F876/7 chips.
>>
Yes - the F874/4 were designed to be drop-in compatible to 16C73/4.
The F876/7  devices are 'enhanced' with this 'shared' RAM block. It
would have been nice if they'd made this feature switchable..