Hello EveryBody, I am working on LCD (16x2) and i have built some of my ideas about LCD programming but i am using Assembly language for my LCD, well as all things was going sweet so as every programmer is having something wrong ... (in starting) my problem specification is that i am using that LCD in 8-bit mode and i have connected my AT89C2051 (with some pull-ups) P1 DB P3.7 RS P3.5 RW P3.4 E and i have interfaced my LCD with my MCu but my problem is that i am getting the LCD not working ... (i dont know why) .... i have interfaced my LCD but there only little bit of contrast....i mean to say that there nothing visible... even i move my 10K-ohm-POT to the ground.....
and i have done some programming, so could any one please help me .... (i am really stucked) any help will be appritiatable.....
<code> ORG 0000H LJMP MAIN ORG 0030H RS EQU P3.7 RW EQU P3.5 EN EQU P3.4 MAIN: LCALL DELAY CLR EN MOV DPTR,#MYCOM LCALL LCD_INI MOV DPTR,#MYDATA LCALL LOOP MOV A,#0C9h LCALL COM LCALL DELAY MOV DPTR,#MYDAT2 LCALL LOOP AGAIN: SJMP AGAIN ;======================================== COM: MOV P1,A CLR RS CLR RW SETB EN LCALL DELAY CLR EN RET ;======================================== DATAW: MOV P1,A SETB RS CLR RW SETB EN LCALL DELAY CLR EN RET ;======================================== DELAY: MOV R6,#100 HERE2: MOV R7,#250 HERE: DJNZ R7,HERE DJNZ R6,HERE2 RET ;======================================== LCD_INI: CLR A MOVC A,@A+DPTR LCALL COM LCALL DELAY JZ GO_B1 INC DPTR SJMP LCD_INI GO_B1: RET ;======================================== LOOP: CLR A MOVC A,@A+DPTR LCALL DATAW LCALL DELAY INC DPTR JZ GO_B2 SJMP LOOP GO_B2: RET ;======================================== MYCOM: DB 38H,0EH,06,01,84H,0 MYDATA: DB "DAREDEVIL",0 MYDAT2: DB "GUNS AND ROSES",0 ;======================================== END </code>
Asif Ali "DareDevil"