Why doesn't my code for 18f452 work on 18f252?

[Bruce]

As Mike already pointed out, you really do need to disable A/D on PORTA.0 with ADCON1 = 7. These pins are by default A/D inputs until you configure them for digital I/O with ADCON1. It may just be a fluke that it's working on the 452 with RA0 configured as an A/D input.

This (below) isn't part of the problem, but if you want the expected results from both statements then change;

LCD_LINES2

to

LCD_LINES 2 ' < -- need the separation

And

If LCD1 => 92 Then

to

If LCD1 >= 92 Then ' = should always be after > when combined.

Also be sure to set HS VS XT or you may not be providing enough drive for the higher speed crystal.

when you run it on the 252 chip the watchdog timer times out

PBP should automatically handle resetting the WDT for you, but if you suspect the WDT is fouling things up, just disable it before programming the part.

[senojlr]

Thanks for the replys guys. I tried everything that you suggested but it did not fix the problem. Out of desperation I was just trying different things and moved the the LCD Data Port from PortC to PortB and it works fine now. I don't know what the difference is because the PortC pins on the 252 and 452 chips are suppose to be the same. If anyone knows what the difference may be I would be interested to know. Anyway thanks again guys and have a Merry CHRISTmas.

RJ