根据Rn单元内容(00H—7FH)，分别转向程序ROUT00—ROUT7FH 参考程序

ROUT00:

ORG 0000H
JMP START

;******************************************************
; Subroutine to perform task for Rn=00H
;******************************************************

TASK_RN00:
; Code to perform task for Rn=00H
RET ; Return from subroutine

;******************************************************
; Main program
;******************************************************

START:
MOV A, #00H ; Load Rn value to A register
CJNE A, #00H, NOT_RN00 ; Check if Rn=00H
CALL TASK_RN00 ; Call subroutine for Rn=00H
JMP END ; Jump to end of program

NOT_RN00:
; Code to handle other Rn values
JMP END ; Jump to end of program

END:
; End of program

ROUT7FH:

ORG 0000H
JMP START

;******************************************************
; Subroutine to perform task for Rn=7FH
;******************************************************

TASK_RN7F:
; Code to perform task for Rn=7FH
RET ; Return from subroutine

;******************************************************
; Main program
;******************************************************

START:
MOV A, #7FH ; Load Rn value to A register
CJNE A, #7FH, NOT_RN7F ; Check if Rn=7FH
CALL TASK_RN7F ; Call subroutine for Rn=7FH
JMP END ; Jump to end of program

NOT_RN7F:
; Code to handle other Rn values
JMP END ; Jump to end of program

END:
; End of program