Multiplexer address control..

[richard]

A little more thought reduces it further,no need at all for a shadow working reg at all
works perfectly on the simulator steps through all 16 "control" states on latb 4-7 and preserves latb 0-3.

; TODO INSERT CONFIG CODE HERE USING CONFIG BITS GENERATOR
  Processor      18f4550
 
  
  include         "p18f4550.inc"   
TRUE  equ 1
FALSE  equ 0
 cblock 0x30 
control     
;latb_shadow   
 endc    
 
 
RES_VECT  CODE    0x0000            ; processor reset vector
    GOTO    START                   ; go to beginning of program
; TODO ADD INTERRUPTS HERE IF USED
MAIN_PROG CODE                      ; let linker place main program
START
   

 



  MOVLW 0f
  MOVWF control
  MOVLW 3
  MOVWF  LATB,A
lopo
  BANKSEL control
  INCF control,F
  MOVLW 0xf
  ANDWF control,F
  
  
  MOVF LATB,A,W
  ANDLW 0XF
  SWAPF WREG,F
  IORWF control,W
  SWAPF WREG,F
  MOVWF LATB ,A
 
  GOTO lopo