Hi there,
I am having this strange problem, hope someone can help
me to understand...I have no hair left on my head :(

Basically, one of the port lines are set as output and low 
at the beginning and later it is switched to an input...Circuit
works for a while then it gets stuck as output...Resetting and
turning off the power does not change the situation...If I reprogram
the PIC problem goes away...I don't understand how that happens...


More detail:
0.1 microF cap is connected to A2 and ground, 1k to 25k resistor
is connected to A2 to +5V.

A2 is initially output and and it is set low which discharges 
the capacitor...
Then it is set as an input and capacitor is charged through R...
I continously check the A2 if it is high...and I count the 
time passed...

>From that I can determine the value of the resistor...

I need to do this once at the start up... So I set the resistor 
(trimpot) to some value and turn the power on...I read something 
within 10% of what I expect...Change the resistor value...push 
the reset button...I read fine again...I repeat this several times...
everything seems fine...

As I try again and again suddenly it stops reading the correct value!!!
A2 gets stuck as output and low...
Resetting, turning off the power does not help...However if I reprogram
the chip it starts to work again...

I switch banks to set porta as input and output...

for example, I use this segment to switch portA bit 2 to an input...

bsf status, rp0
bsf trisa, 2
bcf status, rp0

Any clue is appreciated...Thank you very much for reading so far!

Meric

diehardee@usa.net


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