ここに載っているコトが必ずしも“正しい”とは限らないので、内容を鵜呑みにしないように！

***************1********************
		LIST	P=PIC16F84A
		INCLUDE "P16F84A.INC"
		ORG	0 
-----------------------------------
	MEM22	EQU	22H
	MEM21	EQU	21H
		MOVF	MEM21,0
		SUBWF	MEM22,0
		BTFSC	STATUS,C
		GOTO	SMALL
		GOTO	LARGE
-----------------------------------
LARGE		GOTO 	LARGE
		END

***************2********************


		LIST	P=PIC16F84A
		INCLUDE "P16F84A.INC"
		ORG	0 
-----------------------------------
	MEM1	EQU	20H

		MOVLW	02H
		SUBWF	MEM1,0
		BTFSC	STATUS,C
		GOTO	LARGE
		BTFSC	STATUS,Z
		GOTO	EQUAL
		GOTO	SMALL
LARGE	NOP
SMALL	NOP
EQUAL	NOP
-----------------------------------
LP		GOTO 	LP
		END

***************3********************


		LIST	P=PIC16F84A
		INCLUDE "P16F84A.INC"
		ORG	0 
-----------------------------------
	L45	EQU	11H
		MOVF	L45	D'45'
	LOOP	NOP
		DECFSZ	L45
		GOTO	LOOP
-----------------------------------
LP		GOTO 	LP
		END

***************4********************

		LIST	P=PIC16F84A
		INCLUDE "P16F84A.INC"
		ORG	0 
-----------------------------------

MEM1	EQU		20H
MEM2	EQU		21H
		MOVLW	D'25'
		MOVWF	MEM1
LOOP2	NOP
		MOVLW	D'20'
		MOVWF	MEM2
LOOP1	NOP
		DECFSZ	MEM1,1
		GOTO	LOOP1
		DECFSZ	MEM2,1
		GOTO	LOOP2
-----------------------------------
		GOTO	LP
LP		GOTO 	LP
		END

***************5********************

		LIST		P=PIC16F84A
		INCLUDE	"P16F84A.INC"
		ORG 0
-----------------------------------
		MOVLW	20H
		MOVWF	FSR
		MOVLW	0FFH
LOOP	MOVWF	INDF
		INCF	FSR,1
		BTFSS	FSR,4
		GOTO 	LOOP
-----------------------------------
LP		GOTO	LP
		END

***************6********************

		LIST	P=PIC16F84A
		INCLUDE	"P16F84A.INC"
		ORG 0
-----------------------------------
		MOVLW	0CH
		MOVWF	FSR
		MOVLW	08H
		CALL PP
		MOVLW	0CH
		CALL PP
		MOVLW	04H
		CALL PP
		MOVLW	06H
		CALL PP
LP		GOTO	LP
PP		MOVWF	INDF
		INCF	FSR,1
		RETURN
-----------------------------------
		END