Adam wrote:
>When I do an A/D conversion I get funny results.  If I use right justified,
>ADFM = 1 and try and read 5V... I get something like (011-1000111).
>However as soon as I switch to left justified, ADFM = 0,  I get all 1's (16
>of them)... including the extra 6 bits that should be set to 0..
>(11111111-11111111) - should be (1111111-111000000)
>
>Any Ideas / Help?
>
>
>bsf          STATUS, RP0     ; Select bank 1
>movlw     0x0FF                  ; RA5-0 inputs,
>movwf     TRISA
>movlw     0x02                   ; set all of port E
>movwf     ADCON1           ; to Digital I/O, port A to analog
>clrf          STATUS               ; select bank 0
>movlw       B'11000001'       ;RC osc [7-6], A/D ch0 [5-3], a/d on [0]
>  movwf       ADCON0
>                                         ; need to wait the proper
>acquisition time ~20us
>                                         ;  20us = overhead + (loop time *
>loop count)
>                                         ;  20us = 2us  + (3us * loop count)
>                                          ;   loop count = 6
>
>ADStart:
>movlw     0x06                              ; 1 us
>movwf     DELAY                         ; 1 us
>
>ADConv_Acquisition:                    ; ----loop-----
>decfsz     DELAY, f                          ; 1 us   -
>goto       ADConv_Acquisition          ; 2 us   -
>                                                     ; ----loop-----
>
>
>banksel  ADCON0                       ; additional 2 us... padding
>bsf         ADCON0, GO
>
>
>btfss     ADCON0, GO
>goto     ADReady
>goto    $-2
>
>
>ADReady... just displays the value and goto's ADStart

You do realise that ADRESL & ADRESH are in different banks don't you?
(ADRESH is in bank 0 and ADRESL is in bank 1)
Regards...

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