RA4/TOCKI readout hangs

[cyberant]

I have a problem with RA4/TOCKI
I have a switch on RA4 which switches RA4 to high or low. I try`d my programm with the switch on RA3/AN3 und it works without a problem, but as soon as i connect the switch to ra4 und press it my programm stops and i have no reaction on my RS232 imputs anymore.
Do i have to set RA4 in analog mode or something like this?
Ive allready done: "setup_adc_ports(AN0)"
and my programm works with RA3/AN3 - i suggest the problem must be something with the TOCKI function of RA4 - how can I set RA4/TOCKI to work as a normal digital input? (I already try`d the search function...)

[inservi]

Hello,

What device do you use ?
With some pic as 18f252, the RA4 is different than other RA.

Here is the description from Microchip data sheet

[cyberant]

My switch works correctly - switches between 0-4V (works without problems in AN3).
I use the PIC 16F877
Looks like I found the problem:
enable_interrupts(GLOBAL);
if i enable global interrupts the problem happens. Without this it works fine. But I didn`t write any interrupt routine - so its strange that it doesn`t jump out of the interrupt - or??

[inservi]

Hello,

Could-you send the complete configuration ?


dro
_________________
in médio virtus

[cyberant]

What complete Configuration do u need? I have try`d the switch - works fine on AN3(its no Hardware Problem) but not on AN4 with enable_interrupts(GLOBAL);
I think because it jumps into the interrupt and dont go back into the normal Programm - but Ive not wrote a Interrupt Service Routine or something...

[Ttelmah]

Er.
If you enable interrupts, you _must_ have an interrupt handler (there is no point in enabling interrupts, unless you do have a handler, and without a handler present, with the interrupts enabled, the _hardware_, will jump to the handler, _which is not there..._).

Best Wishes