Implementations of NEXT on 6502
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Implementations of NEXT in Forth Systems for the 6502 CPU#

FIG-FORTH (also X-FORTH, ANTIC FORTH and other derivatives of FIG-FORTH ...)#

NEXT
   LDY #1
   LDA (IP),Y ; Hi-Byte of wordaddress
   STA W+1    ; store in W-Reg
   DEY
   LDA (IP),Y ; Lo-Byte of wordaddress
   STA W      ; store in W-Reg
   CLC
   LDA IP     ; increment IP by 2
   ADC #2
   STA IP
   BCC L54
   INC IP+1
L54
   JMP W-1    ; indirect jump to (W)

64FORTH (Tom Zimmer)#

NEXT  LDY   #1 
             LDA  (IP),Y 
             STA   W+1 
             DEY 
             LDA  (IP),Y 
             STA  W 
             LDA  (W),Y 
             STA  TMP 
             INY 
             LDA  (W),Y 
             STA   TMP+1 
             DEY 
            CLC 
            LDA   IP 
            ADC  #2 
            STA   IP 
            BCC  L816E 
            INC   IP+1 
L816E  JMP  (TMP)
See http://groups.google.de/group/comp.lang.forth/browse_thread/thread/19f7f2102e020583/8d1b52cf069d1258