Re: [CAD_CAM_EDM_DRO] Re: PIC DRO

> From: Larry Edington <larrye@...>
> It is true that even with the F877, the databook says you shouldn't
> poll the port if you are using the interrupt on change feature.
> So, I use the upper nibble for the two encoders, I use the INT0 pin
> ( RB0 ) for a different external interrupt, and the other 3 pins for

outputs

> so there's no polling necessary of the port. ( well other than in the ISR
> to look at the encoder's value )

How long is your ISR (timewise)? You're lucky to have an onboard hardware
USART for the serial interface! My own PIC experience is solely with the C5x
series and I've done quite a lot with software UARTs.

Matt