Writing "Hello World" to LCD Character in the Upper Left firs Line.

In this lesson, you can try to write word " Hello World " in first line of LCD Character.

Step 1st
Build the circuit as shown in figure 2.11. As you seen on figure 2.11. P0.0 trough P0.7 is connected to DB0 - DB7,and P2.0- P2.1. is connected to RS and EN each. Remember, that all we want to do with this lesson is write " Hello World ", in the first line of LCD Character, below the schematic

Step 2nd
In this step, you must tipe the assembly program to make your LCD Character shown the word, we assume that you have already known the editor, we used RIDE-51 to edit the program.

       org 0h
start: call init_LCD
      mov R1,#80h
      call write_inst
      mov R1,#'H'
      call write_data
      mov R1,#'e'
      call write_data
      mov R1,#'l'
      call write_data
      mov R1,#'l'
      call write_data
      mov R1,#'o'
      call write_data
      mov R1,#' '
      call write_data
      mov R1,#'W'
      call write_data
      mov R1,#'o'
      call write_data
      mov R1,#'r'
      call write_data
      mov R1,#'l'
      call write_data
      mov R1,#'d'
      call write_data
EndChar:
      sjmp Endchar

Init_lcd:
   mov r1,#00000001b ;Display clear
   acall write_inst  ;
   mov r1,#00111000b ;Function set,
                     ;Data 8 bit,2 line font 5x7
   acall write_inst  ;
   mov r1,#00001100b ;Display on,
                     ;cursor off,cursor blink off
   acall write_inst
   mov r1,#00000110b ;Entry mode, Set increment
   acall write_inst
   ret
;
Write_inst:
   clr P2.0  ; RS = P2.0 = 0, write mode instruction
   mov P0,R1 ; D7 s/d D0 = P0 = R1
   setb P2.1 ; EN = 1 = P2.1
   call delay; call delay time
   clr P2.1  ; EN = 0 = P2.1
   ret
;
Write_data:
   setb P2.0 ; RS = P2.0 = 1, write mode data
   mov P0,R1 ; D7 s/d D0 = P0 = R1
   setb P2.1 ; EN = 1 = P2.1
   call delay; call delay time
   clr p2.1  ; EN = 0 = P2.1
   ret
;
delay: mov R0,#0
delay1:mov R7,#0fh
      djnz R7,$
      djnz R0,delay1
      ret
;
end

Step 3rd

Safe your assembly program above, and name it with lcd1.asm (for example)
Compile the program that you have been save by using RIDE-51, see the
software instruction.

Step 4th

Download your hex file ( lcd1.hex ) into the microcontroller by using Microcontroller Laros ATMEL ISP software, see the instruction.After download this hex file you'll see the action of the 7 segmen ( of course if your cable connection and your program are corrected ).