Hi Scott,

why not try this

readkey         btfss porta,0
                goto key1_press
                btfss porta,1
                goto key2_press
                retlw 00

key1_press      call debounce
                btfsc porta,0
                retlw 00h
                retlw 01h

key2_press      call debounce
                btfsc porta,1
                retlw 00h
                retlw 02h

Regards

Pailoor


"Mitchell D. Miller" wrote:
>
> Scott,
>
> The problem here is that every time you 'RRF PORTA', the entire port it
> read, and the first bit is rotated into the C bit.  Rather than rotating the
> port each time, you need to read the port into memory first, then rotate
> that data.  Example: (sorry for the mixed Parallax & Microchip mnemonics)
>
>     movw  porta
>     movf   myvar, w
>     rrf       myvar
>     btfsc   status, c
>     goto    code1
>     rrf       myvar
>     btfsc   status, c
>     goto    code2
>     .
>     .
>     .
>
> Only problem this creates is that any changes in portA during processing are
> not recognized until next time through this code.
>
> Mitch Miller
> Omaha, NE
> mdmiller2@home.com
>
> ----- Original Message -----
> From: Scott <spamdogg@webbernet.net>
> To: <PICLIST@MITVMA.MIT.EDU>
> Sent: Tuesday, October 19, 1999 8:02 PM
> Subject: Polling PortA
>
> > I want to use portA to read two switches for one project and four
> > switches for another.  How do I make each bit rotate through the carry
> > flag consecutivly.  I have been using the following code, but it only
> > reads the first bit. I am using a 16c56
> >
> >
> >              movlw         0x0F
> >              tris              PORTA
> >              movlw         0x00
> >              tris              PORTB
> >
> > input      bcf              STATUS, C
> >              rrf               PORTA, W
> >              btfsc            STATUS, C
> >              goto             code_1
> >              rrf               PORTA, W
> >              btfsc            STATUS, C
> >              goto             code_2
> >              goto             input
> >
> > I was able to write the rest of this program and simulate it with
> > success and I have been stareing at this part for four hours with no
> > luck.
> >
> > Scott

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