Hi Bob,

Using your dit_delay_plus_1 cheat, this routine is 12 instructions with 
no restriction on delay corrupting W.

start:
         movwf   tmp
loop:
         movf    tmp,w
         addwf   tmp,f               ;shift left x2
         skpnz
          return                     ;quit if we got 0

         rlf     dit_count,f	    ;carry was set after addwf
         rlf     dit_count,f

         bsf     portb,5
         call    delay_dit_times_plus_1
         bcf     portb,5
         call    delay_dit_times_plus_1
         goto    loop

regards,
Reggie

Robert Ammerman wrote:
> Here is another flavor that really does get down to 12 instructions, but 
> with the restriction that the delay routine cannot modify W
> 
> morse_output:
>     movwf        morse_bits
>     addwf        morse_bits,w
>     skpnz
>     return
>     skpnc
>     bsf            dit_count,1
>     bsf            portb,0
>     call            dit_delay_plus_1
>     bcf            portb,0
>     call            dit_delay_plus_1
>     bra            more_output
> 
> ; This delay routine must preserve W.
> 
> dit_delay_plus_1:
>     incf        dit_count,f        ; instruction number 12
> 
> dit_delay:
>     clrf         inner_count      ; set up inner loop count
> ;    bsf        inner_count,?   ; alternate set up (assumes zero to start)
> dit_inner_loop:
>     decfsz    inner_count
>     goto      dit_inner_loop
>     decfsz    dit_count,f
>     goto        dit_delay
>     return
> 
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