E   EQU P2.7
RW  EQU P2.6
RS  EQU P2.5
LW  EQU P0

ORG 0000H
LJMP LCD
ORG 0030H

LCD:
LCALL DELAY1
LCALL DELAY1

MOV LW,#01H;
LCALL WRITE1
MOV LW,#02H;
LCALL WRITE1 
MOV LW,#06H;
LCALL WRITE1 
MOV LW,#0CH;
LCALL WRITE1 
MOV LW,#18H;
LCALL WRITE1
MOV LW,#38H;
LCALL WRITE1
MOV LW,#80h;
LCALL WRITE1


START1:
MOV LW,#80H
ACALL WRITE1
MOV A,#'A'
MOV LW,A
LCALL WRITE2
LJMP START1

WRITE1:  ;寫指令
CLR RS
CLR RW 
CLR E 
LCALL DELAY1
LCALL DELAY1
SETB E 
RET

WRITE2:  ;寫數據
SETB RS
CLR RW
CLR E
LCALL DELAY1
LCALL DELAY1
SETB E
RET 


DELAY1:  
MOV R7,#250
D1:
MOV R6,#250
D2:
DJNZ R6,D2
DJNZ R7,D1
RET


END