FUNC:
MOV DPTR,#NUM
MOVC A,@A+DPTR
CJNE A,#'A',FUNC1
LJMP PR1
FUNC1:
CJNE A,#'B',FUN2
LJMP PR2
FUNC2:
CJNE A,#'C',FUN3
LJMP PR3
FUN3:
...............
FUNC20:
CJNE A,#'T',FUNC21
LJMP PR20
FUN21:
LJMP PR21
PR1:
MOV R1,#1
LJMP FUNC
PR2:
MOV R1,#2
LJMP FUNC
PR3:
MOV R1,#3
LJPM FUNC
.............
PR21:
MOV R1,#0FFH
LJMP FUNC
NUM:
DB 'A','B','C','D','E','F','G','H','I','J',
DB 'K','L','M','N','O','P','Q','R','S','T'