interrupts

aaronik19 · Joined: 25 Apr 2011 Posts: 297

Hope that everyone is fine! Can someone explain what is the difference between the following interrupts, EXT, int_rb? Is it possible to include RB1-RB3 in the interrupt like RB4-RB7?

Thanks
aaronik19

Ttelmah · Joined: 11 Mar 2010 Posts: 19537

Read the chip's data sheet.
What interrupts are available on a chip, depend on the chip, nothing else.

Some chips allow pins like RB0...3 to be used by INT_RB. Most don't. Some of these have you able to enable/disable INT_RB, on individual pins, and in a few versions, even allow the detection direction to be detected/controlled.
So for the PIC16F1937 (for example), CCS has 'INT_RB0_L2H'.

In general, INT_EXT, responds to a specific change in level on a particular pin (direction settable separately). Normally pin B0. INT_RB, normally responds to any charge on any of the high four pins of port B. and it responds (except on some later chips), to any _change_.

Best Wishes