Hello PIC-List!

To give a short introduction to myself:
Tony Meyer, i've been an enthusiastic german pic
development engineer for several years, worked with
16c74, 17c756, 16f627, 16f84.

I am now currently working on a project involving 3
PICs including intercommunication w/ rs232, 485, i2c,
pid-controlling amongst other things. For development
I use the MPLAB ICE2000 and the PCM17Xa0_module to
emulate the 17c756.

To my question: I am experiencing strange (i.e. no)
action working on ra4&5. these are documented to
be multiplexed with usart1, which already worked fine.

What I'm trying to do now is to disconnect the port
pins from the usart module and use them as general
i/o. I've cleared RCSTA1,SPEN and tried to manipulate
the ports. Getting no results I wrote a few lines of
code to make an isolated test situation. Test code
below.

There is nothing else connected to these ports - when
I start the program -nothing- happens on the port pins
ra4/5 (ports stay lo). I've already tried to add
pullup-resistors (10k), no change but the pins stay
hi.

I also tried to burn the sw in silicone but no change
in behaviour. The open drain outputs ra1/2 behave like
expected.

any help would be very appreciated!

thanks in advance,
regards,
T.M.

----

test code here:

        org     0x000
        movlr   0
        movlb   0
        goto    start

; isr's here

start
        movlw   B'10111100'
        movwf   PORTA
        nop
        movlw   B'10000000'
        movwf   PORTA
        goto    start



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