Steve,

Code looks fine to me, except one point - Why do you have an XOR on the
registers ?  e.g. on TRISIO ?  Just looking at some of my code and
MicroChip code which initialises these registers, neither of which use
an XOR.  I thought this was the function of changing to Bank1 using the
STATUS,RP0 flag ?

I'm still new to this PIC Assembler so I may be wrong on this, but
that's the only thing that stood out to me as being different to the
code I've seen and written, which works fine.

Andy

stesquib@MINES.EDU wrote:
> Hello, The following ADC code for a 12F675 constantly returns zero (puts 0 in
> ADRESH).
>
> ;******** Initialization ************
>  clrf   GPIO
>  clrf   INTCON
>
>  bsf    STATUS,RP0
>  movlw  0x0FC
>  movwf  TRISIO ^ 0x080          ;GPIO 0,1 are outputs
>  movlw  0x080
>  movwf  OPTION_REG ^ 0x080      ;pullups off
>  movlw  0x05                    ;Fosc/16, AN3 (GPIO4) is analog input
>  movwf  ANSEL ^ 0x080
>  clrf   PIE1 ^ 0x080
>  bcf    STATUS,RP0
>
>  clrf   N
> ;****** END Initialization **********
>
>
> ;************* Main *****************
> main
>  movlw  0x00C                   ;left justified, channel 3 (gpio 4)
>  movwf  ADCON0                  ;Vref = Vdd
>
>  movlw  7                       ;wait for adc to charge
>  addlw  0x0ff
>  btfss  STATUS,Z
>   goto  $ - 2
>
>  bsf    ADCON0,GO               ;start ADC
>  btfsc  ADCON0,GO               ;allow ADC to finish
>   goto  $ - 1
>
>  movf   ADRESH,w
>  movwf  N                       ;place 8 upper bits in N
>
>  call   Serout                  ;output N
>
>  call   onesec
>  goto   main
> ;*********** End Main ***************
>
> If anyout could clear this up for me I'de be gateful.
> Thx, Steve
>
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--
Andy Pryer

Email:   andy.pryer@cubecomputing.com
Web:     http://www.cubecomputing.com
Tel/Fax: 01582 703872
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