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Help needed for LCD programming in asm

natur3 t0mAt0

Hi all.. Im quite new to 8051. Im doing a project that requires me to display value of a peak voltage on a LCD.

Anyway, Im stuck in testing the LCD. I have connected the LCD(Powertip PC 0802-A), otherwise known as 214-3288, to my 8051 development kit. The kit that im using is C8051F206-TB. I connected databus 0-7 to port 3 and RS to P2.4, R/W to P2.5, and EN to P2.6

I also have gone online to source for programs to display "Hello World" on the LCD. I have found a few in C or asm, but i have learnt the basic of assembly language, so i don't really understand C language.

Below is a program i found in 8052.com

$include (c8051f200.inc)

CSEG AT 0000H
LJMP MAIN
CSEG AT 0100H

MAIN:LCALL CONFIG
     LCALL INIT_LCD
     LCALL CLEAR_LCD
     LCALL HELLO

CONFIG:MOV PRT0MX, #000H ; PRT0MX: Initial Reset Value
       MOV PRT1MX, #000H ; PRT1MX: Initial Reset Value
       MOV PRT2MX, #000H ; PRT2MX: Initial Reset Value
       MOV P2MODE, #0FFH ; Input Configuration for P2
       MOV PRT3CF, #0FFH ; Output configuration for P3

INIT_LCD:       CLR P2.4
         MOV P3,#38H
        SETB P2.6
        CLR P2.6
        LCALL WAIT_LCD
        CLR P2.4
        MOV P3,#0EH
        SETB P2.6
        CLR P2.6
        LCALL WAIT_LCD
        CLR P2.4
        MOV P3,#06H
        SETB P2.6
        CLR P2.6
        LCALL WAIT_LCD
        RET

HELLO:  LCALL INIT_LCD
        LCALL CLEAR_LCD
        MOV A,#48H
        LCALL WRITE_TEXT
        MOV A,#45H
        LCALL WRITE_TEXT
        MOV A,#4CH
        LCALL WRITE_TEXT
        MOV A,#4CH
        LCALL WRITE_TEXT
        MOV A,#4FH
        LCALL WRITE_TEXT
        CLR P2.4
        MOV P3,#0CAH
        SETB P2.6
        CLR P2.6
        LCALL WRITE_TEXT
        MOV A,#57H
        LCALL WRITE_TEXT
        MOV A,#4FH
        LCALL WRITE_TEXT
        MOV A,#52H
        LCALL WRITE_TEXT
        MOV A,#4CH
        LCALL WRITE_TEXT
        MOV A,#44H
        LCALL WRITE_TEXT

WAIT_LCD:       CLR P2.6 ;Start LCD command
        CLR P2.4 ;It's a command
        SETB P2.5 ;It's a read command
        MOV P3,#0FFH ;Set all pins to FF initially
        SETB P2.6 ;Clock out command to LCD
        MOV A,P3 ;Read the return value
        JB ACC.7,WAIT_LCD
        CLR P2.6 ;Finish the command
        CLR P2.5 ;Turn off RW for future commands
        RET


CLEAR_LCD:CLR P2.4
        MOV P3,#01H
        SETB P2.6
        CLR P2.6
        LCALL WAIT_LCD
        RET

WRITE_TEXT:SETB P2.4
          MOV P3,A
          SETB P2.6
          CLR P2.6
          LCALL WAIT_LCD
          RET



           END

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