pin 12f683

[jcleaver]

great info bruce
i think i want internal pull ups
is this wpu=1
thanks for your help

[Bruce]

GPIO.0, 1, 2, 4 and 5 have pull-up enable/disable bits in WPU, but
OPTION_REG.7 needs to be clear also.

OPTION_REG.7 (GPPU) is the global pull-up enable/disable bit.

OPTION_REG.7 = 0 ' GPIO pull-ups enabled by individual WPU bits
TRISIO = %00000001 ' GPIO.0 = input, rest outputs (except for GPIO.3)
WPU = %00000001 ' enable pull-up on GPIO.0, disable the rest.

It's pretty straight forward. Look in your data sheet under OPTION_REG &
WPU sections for details.

[jcleaver]

have set this up on a board which has a resistor 10 k to ground and a pb to vdd on gpi0.5. this is the way the board is set trying some programs but
gpi0.5 stays high whenever pic is in socket i guess somehow i am not shutting off the pullups on this port have tried many many lines no changes to this
any ideas whats up doc

[Bruce]

Post the code you're having problems with. Hard to say without seeing that.

[jcleaver]

got most things working now except
cannot get changover from 1 to 0 on gpio.0
its going high due to the pullup but when i ground does not respond

might not be explaining this properly but can work on gpio.5

where i have a resistor to gnd and a pb to 5 volts

[jcleaver]

What Seems To Be Happening Is I Cannot Get Gpi0.0 To Change State Using The Pullup
Dont Know If Its A Electrical Issue Or Not See Sample Program Above Just Grounding Pin 7 Momentarily
But Prgram Does Not Respond Works On Gpi0.5 With A Res Pulled Low And A Pb To High

[Bruce]

Which PIC are you actually using? Your code example above indicates a 12F675, but you asked about the 12F683?

For the 12F675 you need CMCON = 7 to disable comparators.
For the 12F683 you need CMCON0 = 7 to disable comparators.