Ken,

Make sure that you have selected internal MCLR, since the unprogrammed
state is for external reset and makes GP3 an input. Check to make sure that
Timer 0 is not configured as a counter which would make GP2 an input. It
looks like it defaults to being a counter.

Kind Regards,

Greg Maki

At 05:39 PM 1/24/98 +0000, you wrote:
>Can anyone tell me why this does not work, I have a 508 configured for
>int RC osc and int Reset with NO WDT.
>
>temp            equ     0x1c    ;File reg for temp storage
>
>        ORG     0               ;set start of program to 000 hex
>        movwf   OSCCAL
>
>start
>        clrf    GPIO
>        movlw   B'000000'       ;set all bits output
>        tris    GPIO
>        clrf    temp
>start2
>        incf    temp
>        movf    temp,w
>        movwf   GPIO
>        goto    start2          ;go and do it all again
>
>        END
>
>This gives the expected square wave output on GP0, GP1, GP4, GP5 but
>there is no outputs on GP2 and GP3. I have come to this simple loop
>because the main program that I have working in a 508 with XT osc stops
>working when I try and use the int RC osc.
>
>Ken.
>
>
>+-----------------------------+--------------------------------------------+
>|      Ken Hewitt  G8PWC      |        Email ken@welwyn.demon.co.uk        |
>|      /\/\/\/\/\/\/\/\/      |  Homepage   http://www.welwyn.demon.co.uk  |
>+-----------------------------+--------------------------------------------+
>
>