I am using a PIC16F873A, I am connecting the output pins directly to an ATMEL microcontroller, the ATMEL microcontroller have pullup resistors in the corresponding inputs, but the initial state of all my output pins is set to High in the begginning of the program for the ATMEL microcontroller be compatible with negative logic.

I am using the USART of the PIC using an Assembler routine for the interrupt handler. When I send certain message to the USART via itīs input, the program evaluates the message, then changes the pin outputs, now I am working with PAUSE 10 between each output statement.

I can not assign directly to PORT registers because of the USART connected to some pins of PORTC.

Thanks for all your answers!