Pic16f628 and pic16f628a

[dr pepper]

I know this question has probably been asked before, another post reminded me to ask this one.
I have a project that uses a '628a, it makes use of the rs232 port and also the external osc on timer1 with a 32kc xtal.
I programmed a '628 and plugged it in just to see if it didnt work, it didnt timer 1 didnt oscillate which was to be expected as the osc on the '628 is different, but the rs232 didnt work either, even when I doctored the code.
Does the '628 not have a uart and the '628a does?, looks like it.

 

[Nigel Goodwin]

No, the 'a' is just a 'later silicon revision', only extremely slight changes are required, basically the config fuse settings - the specs are identical.

Try looking at the datasheets.

 

[dr pepper]

Timer 1 on the '628 is rated for 200kc, whereas the 'a' is 32kc, so the osc setup could be diffrent, maybe thats why the timer isnt running.
The migration data sheet doesnt mention anything about the uart, maybe the pic I tried was a duffer.