reset works for PIC16F877 but not on PIC18F452

[ericmar]

reset circuit of pic16f877a

Hi,

I have a reset mechanism incorporated into my circuit using the PIC16F877 first, then using the PIC18F452 (for future enhancements to software). The problem I have is that the reset works fine on the PIC16F but not at all on the PIC18F despite using the same circuit and both ICs having identical pin layouts.

I'm guessing it could be the configuration bits used to compile the project, but i'm not totally sure. Here are the ones used for the PIC16F:

__CONFIG(XT & WDTDIS & PWRTEN & LVPDIS & DUNPROT & DEBUGDIS);

I used the same configurations bits for the PIC18F too but there were many more which i wasn't sure of.

Does anyone know how to fix this?

Thank you

 

[123jack]

The two chips will respond differently even if the pinouts are identical, often
an 18F will have extra functions on the same pin or will need setting up differently. They are different chips - porting is designed to be fairly easy but you can't just copy one application to the other chip and expect it to work.

I suggest you start by comparing the pin functions in the 2 datasheets.

jack