#define     SDO     PORTA,0
#define     SCK     PORTA,1
#define     CS      PORTA,2

SEND        EQU     0x20

SPISend     bcf     CS          ;chip select lo
        movlw       0x08            ;initialize bit counter
        movwf       BITCOUNT

        btfss       SEND,7          ;is MSB in send register high?
        goto        SendLow         ;no, send 0

SendHigh    bsf     SDO         ;send 1
        goto        Shift

SendLow     bcf     SDO         ;send 0
        goto        Shift

Shift       bsf     SCK         ;pulse clock
        bcf     SCK
        rlf     SEND,F          ;shift bits to the left
        decfsz      BITCOUNT,F      ;decrement bit counter
        goto        $-10            ;loop back if bit counter > 0
        bsf     CS          ;bit counter = 0, chip select hi
        return