#include"lcd.asm"       ; assembly file is included for displaying lcd characters

Main:

PORTA EQU 0xF80  ; PORTS

PORTB EQU 0xF81

PORTC EQU 0xF82

PORTD EQU 0xF83

REG      EQU 0X7F

COUNT EQU 255

EEDATA EQU 0XFA8

TRISA EQU 0xF92    ; DATA CONTROL REGISTER

TRISB EQU 0xF93

TRISD EQU 0xF95

TRISC EQU 0xF94

count1              RES 1           ;variable used in delay routines

counta              RES 1           ;variable used in delay routines

countb              RES 1           ;variable used in delay routines

 #define lcd_data    LATC        ;8 bit data to the lcd will be on PORTC

 #define lcd_rs      LATA,0      ;register Select (see note at top of program)

 #define lcd_rw      LATA,1      ;read/write, write = 0

 #define lcd_en      LATA,2      ;enable data transfer

 #define lcd_busy    PORTC,7     ;lcd busy flag is read on lcd DB7

ORG 0h          ;

 

CALL init_lcd            ;call the initialization routine

CALL Delay30           ;wait here after initialization routine done.

CLRF TRISD ; port d outport

MOVLW 0Fh ; PIN 0-3 AS INPUT AND 4-7 AS OUTPUT

MOVWF TRISC        ;VALUE TO TRISC

L1:

            MOVLW 0x06 ; SHIFT CURSOR POSITION BY 1

            CALL lcd_write         ;write to lcd

            CALL  get_char          ;code to converthex to ascii

            SUBLW 0xA7 ;CHECKING FOR CLEAR CHARACTER

                        BZ L2 ;BRANCH TO LOOP L2 TO CLEAR TH LCD

            MOVLW REG

            SUBLW 0x17 ; compare for addition key '+'

                        BZ L3

            CALL lcd_write

            CALL DELAY

            GOTO L1

L2:      

            movlw   b'00000001'   ;CLEAR DISPLAY(0x01)

    call    lcd_write       ;WRITE COMMAND TO LCD

    call    busy               ; CHECK BUSY FLAG

            GOTO L1

L3:

            CALL ADDITION

ADDITION

            ADDWF REG,0,1 ;SUM WILL BE STORED IN W REGISTERS

            DAW

RETLW

**********************get_char_routine*******************

get_char

            call scan_keypad

            MOVWF PORTD ; SENDING DATA TO PORTD FOR GLOWING LED'S

            ADDLW 0x30            ;converting hex to ascii

RETLW

***********************SCAN_KEYPAD ROUTINE**************

 

scan_keypad               ;THIS IS THE ROUTINE FOR SCANNING THE KEYPAD AND RETURNING THE VALUE IN W REGISTER

K1:      MOVLW EEh ; (1110 1110) FOR 1

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING BACK FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,4,0      ;BIT 4 IS MADE LOW

            BTFSS W,0,0  ;BIT 0 IS CHECKED IF ITS 1

            RETLW EEh

            GOTO K2

K2:

            MOVLW EDh ; (1110 1101) FOR 2

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,4,0      ;BIT 4 IS MADE LOW

            BTFSS W,1,0  ;BIT 1 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW EDh

            GOTO K3

K3:

            MOVLW ECh ; (1110 1011) FOR 3

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,4,0      ;BIT 4 IS MADE LOW

            BTFSS W,2,0  ;BIT 2 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW ECh

            GOTO K4

K4:

            MOVLW E7h ; (1110 0111) FOR A or '+'

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,4,0      ;BIT 4 IS MADE LOW

            BTFSS W,3,0  ;BIT 3 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW E7h

            GOTO K5

K5:

            MOVLW DEh ; (1101 1110) FOR 4

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,5,0      ;BIT 5 IS MADE LOW

            BTFSS W,0,0  ;BIT 0 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW DEh

            GOTO K6

K6:

            MOVLW DDh ; (1101 1101) FOR 5

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,5,0      ;BIT 5 IS MADE LOW

            BTFSS W,1,0  ;BIT 1 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW DDh

            GOTO K7

K7:

            MOVLW DBh ; (1101 1011) FOR 6

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,5,0      ;BIT 5 IS MADE LOW

            BTFSS W,2,0  ;BIT 2 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW DBh

            GOTO K8

K8:

            MOVLW D7h ; (1101 0111) FOR B or '-'

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,5,0      ;BIT 5 IS MADE LOW

            BTFSS W,3,0  ;BIT 3 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW D7h

            GOTO K9

K9:

            MOVLW BEh ; (1011 1110) FOR 7

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,6,0      ;BIT 6 IS MADE LOW

            BTFSS W,0,0  ;BIT 0 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW BEh

            GOTO K10

K10:

            MOVLW BDh ; (1011 1101) FOR 8

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,6,0      ;BIT 6 IS MADE LOW

            BTFSS W,1,0  ;BIT 1 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW BDh

            GOTO K11

K11:

            MOVLW BBh ; (1011 1011) FOR 9

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,6,0      ;BIT 6 IS MADE LOW

            BTFSS W,2,0  ;BIT 2 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW BBh

            GOTO K12

K12:

            MOVLW B7h ; (1011 0111) FOR C or '*'

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,6,0      ;BIT 6 IS MADE LOW

            BTFSS W,3,0  ;BIT 3 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW B7h

            GOTO K13

K13:

            MOVLW 7Eh ; (0111 1110) FOR *

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,7,0      ;BIT 7 IS MADE LOW

            BTFSS W,0,0  ;BIT 0 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW 7Eh

            GOTO K14

K14:

            MOVLW 7Dh ; (0111 1101) FOR 0

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,7,0      ;BIT 7 IS MADE LOW

            BTFSS W,1,0  ;BIT 1 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW 7Dh

            GOTO K15

K15:

            MOVLW 7Bh ; (0111 1011) FOR #

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,7,0      ;BIT 7 IS MADE LOW

            BTFSS W,2,0  ;BIT 2 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW 7Bh

            GOTO K16

K16:

            MOVLW 77h ; (0111 0111) FOR D or 'C' for clear

            MOVWF PORTC       ; COPYING DATA TO PORT C

            MOVF PORTC,W ;READING COLUMNS FROM PORTC AND COPYING DATA IN W REGISTERS

            BCF W,7,0      ;BIT 7 IS MADE LOW

            BTFSS W,3,0  ;BIT 3 IS CHECKED IF ITS 1 NEXT INSTRUCTION WILL BE SKIPPED

            RETLW 77h

            GOTO K17                

K17:

            RETLW 0FFh ; RETURN 0XFF IF NOTHING IS PRESSED

***********************SCAN_KEYPAD ROUTINE ENDS**********************

******DELAY SUBROUTINE*************

DELAY

            DECFSZ COUNT,1

RETURN

end

 END

Posted Date: 3/5/2013 4:24:41 AM | Location : United States

Ask an Expert

Related Discussions:- Program for dispaying lcd characters, Assignment Help, Ask Question on Program for dispaying lcd characters, Get Answer, Expert's Help, Program for dispaying lcd characters Discussions

Write discussion on Program for dispaying lcd characters
Your posts are moderated

Write your message here..

Related Questions

Program that will display a list of the decades , Write an assembly languag... Write an assembly language program that will display (print) a list of the Decades 2010, 2020, 2030... 2100 to the screen using a while loop.

Data copy/transfer instructions-microprocessor, Data copy/transfer Instruct... Data copy/transfer Instructions MOV: This data transfer instruction transfers data from one register or memory location to another register or memory location. The source can

Internal architecture of microprocessor, Internal Architecture of Microproc... Internal Architecture of Microprocessor : The architecture of 8086 provides a number of improvements over 8085 architecture. It supports a, a set of 16-bit registers ,16-bit AL

16f877 7seg display, do you have experts that know 4 digit 7_Seg dispaly do you have experts that know 4 digit 7_Seg dispaly

Program for generate mips assembly code that runable on spim, Project Overv... Project Overview In this series of projects you will write a compiler for a small subset of Pascal.  In this assignment, you will start writing the syntax analysis and code gen

Cryptography, Write a program that allows a user to encrypt/decrypt a mess... Write a program that allows a user to encrypt/decrypt a message using a shift cipher. The user should specify the key and the message. Your program should be able to handle messa

Write a mips assembly language program, Write a MIPS/SPIM assembly language... Write a MIPS/SPIM assembly language program that prints the smallest and largest values found in a non-empty table of N word-sized integers. The address of the first entry in your

Icwi-microprocessor, The definitions of the bits in ICWI are following: ... The definitions of the bits in ICWI are following: Always set to the value 1. It directs the received byte to ICWI as oppose to OCW2 or OCW3. Which also utilize the even addr

Linking a program-microprocessor, Linking a program The DOS linking pro... Linking a program The DOS linking program LINK.EXE links the different object modules of function library routines and source program to produce an integrated executable code o

Daa-arithmetic instruction-microprocessor, DAA: Decimal Adjust Accumulator... DAA: Decimal Adjust Accumulator:- This instruction is utilized to convert the result of the addition operation of 2 packed BCD numbers to a valid BCD number. The conclusion has to