Dip switch with 4 bits:

DIP       |           Time
-------------------------------
0000     |           1ms
0001     |           2ms
0010     |           3ms
0011     |           4ms

;============================================

Assuming that you have the dip sw on PortB. Don't forget
to use pull-downs on inputs !! that are floating when dip sw
contacts are open !!

         movf   portb,w       ;get value of dip sw
         movwf  dtime         ;into variable

;possibly mask non-switch bits

         movlw   b'00001111'
         andwf    dtime,f             ;eg dip sw on only b0 to b3

;-------------------------------------

;possibly test for dtime = 00 if you don't want a 256ms delay

         movf    dtime,f
         btfss    status,z      ;z=1 if dtime=00

;........valid non-00 switch value, use it, goto rest of program
;........invalid switch value, ie = 00, goto somewhere else

;--------------------------------------

         movf    dtime,w    ;get original (stays intact for other routines)
         movwf c_dtime    ;copy it

         call   msdelay       ;call 1ms delay "dtime" times
         decfsz c_dtime,f  ;destroy copy
         goto   $-2

;........ rest of code

;=====================================

;1ms delay - call 100us delay 10 times

msdelay

         movlw  0xf6
         movwf  cnt1
         call   delay100
         incfsz cnt1,f           ;count up to 00
         goto   $-2              ;call 100us again
         return

;100us delay at 217ns instruction cycle (18.432MHz, my example)

delay100

         movlw  0x62          ;use Stopwatch to optimise for 100us
         movwf  cnt2
         incfsz cnt2,f           ;count up to 00
         goto   $-1
         return

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