On Wed, 21 Apr 2004 19:30:35 -0700, Jason S <pic@CANADASPEAKS.COM> wrote:

> I'm using a 12F675 for the first time and I'm getting some very strange
> behaviour.
>
> At this point, I have a simple program that just sets all the outputs.
> I have GP0, GP1, and GP2 connected to an RGB led through 220 ohm
> resistors.  The LED dies are lit up to a barely noticable brightness.
>
> When I measure the outputs I get about 15 milivolts.  I can't measure
> anything across the resistor, and there's about 15 milivolts and 10
> microamps across and through the LED segments.
>
> I'm powering the circuit from 3 new AA batteries (and I did test them).
>
> My whole source code is:
>
> START MOVLW b'10001111'
>   OPTION
>   CLRF 5
>   MOVLW   b'00001000'
>   TRIS 5
>   BSF  5,0
>   BSF  5,1
>   BSF  5,2
>   BSF  5,4
>   BSF  5,5
>   END
>
> I know I shouldn't be using OPTION and TRIS, but that shouldn't stop it
> from working.
>
> My config bits are:
> Osc:  Internal RC No Clock
> WDT: Off
> Power Up Timer: On
> Master Clear Enable: Internal
> Brown Out Detect: On
> Code Protect: Off
> Data EE Read Protect: Off
>
> Any ideas what I'm doing wrong here?

Not disabling the comparators; by default GP0 and GP1 are comparator pins
rather than digital IO.

BTW, *please* use mnemonics (like "GPIO") for registers rather than
numbers when presenting code for other people to read.

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