Brooke asked:
>
>I would like to use a few 74HC595 shift registers to get 24 bits
>of latched data output.  Could someone help me with the correct
>

It's easy if you may reserve 4 PIC outputs (say PB0 to PB3)'to interfacing
and make the following wiring:

(1) all 3 SRCK (clock) inputs (pin 11 of the 74HC595) tied to PB0, it will
be your strobe signal;
(2) PB1 to PB3 connected to the SER (pin 14) input of each 74HC595.

To strobe out all 24 bits, let's suppose the data are in dat0,dat1,dat2,
and we have a counter in count, and tmp as a temporary storage:

store   movlw   .8
        movwf   count
        clrf    tmp
stloop  rlf     dat2,f
        rlf     tmp,f
        rlf     dat1,f
        rlf     tmp,f
        rlf     dat0,f
        rlf     tmp,f
        bcf     _c       ;clear carry to do not clock yet
        rlf     tmp,f
        movf    portb,w  ;read portb (do not disturb other bits!)
        andlw   0f0h
        iorwf   tmp,w
        movwf   portb    ;write back resulting byte
        bsf     portb,0  ;make a clock pulse
        bcf     portb,0
        decfsz  count    ;repeat for all 8 bits
        goto    stloop
        return           ;return (if this will be a sub-routine :-)

I hope this helps you.  Perhaps some code optimization may be done, but this
is clear and understandable. (Any takers?)

regards,
Rildo Pragana