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2.4.4. Moving Character on LCD
This lesson is learn how to make you word on LCD moving arround, actualy it's just a simple case, by executing sift right or left instruction. see table cursor of display sift

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

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 MIDE-51 to edit the program. ( Download File asm : exp244.zip , Download Complete Circuit File : LCDCharacter.PDF ))

       org 0h
       call init_LCD
start: call write_char; writing a word
;
       mov R2,#10     ; number data tobe sift
siftR: call sift2right
       djnz R2,siftR  ; counting down number data
;
       mov R2,#10
siftL: call sift2right
       djnz R2,siftR
       sjmp start
;
write_char:       
       mov dptr,#word1 ;DPTR = [ address word1 ]
       mov r3,#16      ;R3=16,number character to be display
       mov r1,#80h     ;R1=80h,address DDRAM start position
       acall write_inst
;
write1:clr a           ; A = 0
       movc a,@a+dptr  ; A = [A+ DPTR]
       mov r1,A        ; R1 = A 
       inc dptr        ; DPTR = DPTR +1 
       acall write_data;    
       djnz r3,write1  ; R3 = R3-1, 
       ret
;
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
;
sift2left:
     mov R1,#00011011b ;R1 = sift2left
     call write_inst        
     call ldelay            
     ret
;
sift2Right:
     mov R1,#00011111b ;R1 = sift2right
     call write_inst        
     call ldelay            
     ret
;
delay: mov R0,#0
delay1:mov R7,#0fh
       djnz R7,$
       djnz R0,delay1
       ret
;
Ldelay:mov R6,#030h
Ld1:   call delay
       djnz R6,Ld1
       ret
;
word1: DB '  Welcome Home  '; here is the data to be look up
;
end

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Lesson 1:
T o o l
1.1. Programmer
1.2. Edsim 51
1.3. MIDE-51
1.4. ATMEL ISP

Lesson 2:
Input Output
2.1.LED
2.2.Swicht
2.3.7 Segmen
2.4.LCD Character
2.5.ADC
2.6.DAC
2.7.Motor Stepper
2.8.Keypad

Lesson 3:
Timer Counter
3.1.Basic
3.2.Mode 0
3.3.Mode 1
3.4.Mode 2
3.5.Mode 3

Lesson 4:
Serial Comm.
4.1.Basic
4.2.LED
4.3.Rotate LED
4.2 ADC
4.3.LCD

Lesson 5:
Interuption
5.1.Basic
5.2.Timer
5.2.External