LCD 2x16 characters & 4x4 keypad example
Connect AT90S2313 with LCD display 2x16 char and 4x4 keyboard (keypad). Its not any special code (short or fast code) but its very good for beginners
Designed by: Serasidis Vasilis
Connect AT90S2313 with LCD display 2x16 char and 4x4 keyboard (keypad). Its not any special code (short or fast code) but its very good for beginners
Designed by: Serasidis Vasilis
| CODE |
; ;* Description: Test program with AT90S2313 AVR RISC Processor, ;* LCD display using 4-wire interface and 4x4 keypad. ;* ;* Writed at: 27-05-2003 ;* Target: AT 90s2313 ;* Author: Serasidis Vasilis ;* Support E-mail: info@serasidis.gr ;* Home page: http://www.serasidis.gr ;* ;* LCD rs pin connected to PD6 ;* LCD r/w pin connected to PD5 ;* LCD e pin connected to PD4 ;* D4-D7 FROM LCD IS CONNECTED TO PORTD PD0-PD3 ;* The 4x4 keypad is conected to PortB pins (PB0-PB7) ;* PB0,PB1,PB2,PB3 inputs, PB4,PB5,PB6,PB7 outputs ;* ;* ;* This source its free, for all of you. ;* ;*************************************************************************** .include "2313def.inc" ;Define chip particulars ;***** Global register variables .def wreg =R16 ;General use working register .def timeout =R17 ;Timeout value passed to subroutine .def lcdstat =R18 ;LCD busy/wait status .def longtime=R19 ;Long timer for powerup .def temp =R20 .def test =R21 ;test register .def monades =R22 .def dekades =R23 ;***** Other equates .equ lcdrs =PD6 ;LCD rs pin connected to PD6 .equ lcdrw =PD5 ;LCD r/w pin connected to PD5 .equ lcde =PD4 ;LCD e pin connected to PD4 .equ line1 =0x80 ;1η γραμμη του LCD .equ line2 =0xC0 ;2η γραμμη του LCD .equ col1 =0b11101111;ολόνα 1 .equ col2 =0b11011111;ολόνα 1 .equ col3 =0b10111111;ολόνα 1 .equ col4 =0b01111111;ολόνα 1 ; Main program entry point on reset reset: ldi temp,RAMEND out SPL,temp ;Init Stack Pointer rcall longdelay ;Delay some time ldi temp,0b11110000 ;PB0,1,2,3 inputs, PB4,5,6,7 outputs out DDRB,temp ldi temp,0b00001111 ;enable internal pull-ups on PB0-PB4 out PORTB,temp rcall lcdinit ;Initialize LCD module again: ldi monades,$30 ldi dekades,$30 rcall lcdclr ;Clear the LCD ldi wreg,line1 ;Set address to line 1 rcall lcdcmd ldi ZH,high(2*message1);Type the message1 ldi ZL,low(2*message1);to the LCD rcall loadbyte ldi wreg,line2 ;Set address to line 2 rcall lcdcmd ldi ZH,high(2*message2);Type the message2 ldi ZL,low(2*message2);to the LCD rcall loadbyte ;========================================================================= ; Check all keys (1-16). ; The comments from the first 4 keys are the same with all other keys. ;========================================================================= check_keys: ldi temp,col1 ;Enable column1 out PORTB,temp rcall delay sbic PINB,PB0 ; Pressed key No1 ? rjmp key2 ; if Not, check next key ldi monades,$31 ; if yes... rjmp disp_no_of_key ; goto type it to LCD key2: sbic PINB,PB1 ; Pressed key No2 ? rjmp key3 ; if Not, check next key ldi monades,$32 ; if yes... rjmp disp_no_of_key ; goto type it to LCD key3: sbic PINB,PB2 ; Pressed key No3 ? rjmp key4 ; if Not, check next key ldi monades,$33 ; if yes... rjmp disp_no_of_key ; goto type it to LCD key4: sbic PINB,PB3 ; Pressed key No4 ? rjmp key5 ; if Not, check next key ldi monades,$34 ; if yes... rjmp disp_no_of_key ; goto type it to LCD key5: ldi temp,col2 ; Disable the first column... out PORTB,temp ; and enable the second rcall delay sbic PINB,PB0 ; Pressed key No5 ? rjmp key6 ; if Not... ldi monades,$35 ; rjmp disp_no_of_key key6: sbic PINB,PB1 ; Pressed key No6 ? rjmp key7 ; if Not... ldi monades,$36 ; rjmp disp_no_of_key key7: sbic PINB,PB2 ; Pressed key No7 ? rjmp key8 ; if Not... ldi monades,$37 ; rjmp disp_no_of_key key8: sbic PINB,PB3 ; Pressed key No8 ? rjmp key9 ; if Not... ldi monades,$38 ; rjmp disp_no_of_key key9: ldi temp,col3; out PORTB,temp rcall delay sbic PINB,PB0 ; Pressed key No9 ? rjmp key10 ; if Not... ldi monades,$39 ; rjmp disp_no_of_key key10: sbic PINB,PB1 ; Pressed key No10 ? rjmp key11 ; if Not... ldi monades,$30 ; ldi dekades,$31 rjmp disp_no_of_key key11: sbic PINB,PB2 ; Pressed key No11 ? rjmp key12 ; if Not... ldi monades,$31 ; ldi dekades,$31 rjmp disp_no_of_key key12: sbic PINB,PB3 ; Pressed key No12 ? rjmp key13 ; if Not... ldi monades,$32 ; ldi dekades,$31 rjmp disp_no_of_key key13: ldi temp,col4; out PORTB,temp rcall delay sbic PINB,PB0 ; Pressed key No13 ? rjmp key14 ; if Not... ldi monades,$33 ; ldi dekades,$31 rjmp disp_no_of_key key14: sbic PINB,PB1 ; Pressed key No14 ? rjmp key15 ; if Not... ldi monades,$34 ; ldi dekades,$31 rjmp disp_no_of_key key15: sbic PINB,PB2 ; Pressed key No15 ? rjmp key16 ; if Not... ldi monades,$35 ; ldi dekades,$31 rjmp disp_no_of_key key16: sbic PINB,PB3 ; Pressed key No16 ? rjmp check_keys ; if Not... ldi monades,$36 ; ldi dekades,$31 rjmp disp_no_of_key ;========================================================================= ; Here is typed the message3 ,message4, dekades and monades to LCD ;========================================================================= disp_no_of_key: rcall lcdclr ; Clear the LCD ldi wreg,line1 ; Set address to line 1 rcall lcdcmd ldi ZH,high(2*message3); Load high part of byte address into ZH ldi ZL,low(2*message3); Load low part of byte address into ZL rcall loadbyte ldi wreg,line2 ; Set address to line 2 rcall lcdcmd ldi ZH,high(2*message4); Load high part of byte address into ZH ldi ZL,low(2*message4); Load low part of byte address into ZL rcall loadbyte mov wreg,dekades rcall lcdput mov wreg,monades rcall lcdput rcall longdelay ;Wait some time rjmp again ;========================================================================= ; Clear entire LCD and delay for a bit ;========================================================================= lcdclr: ldi wreg,1 ;Clear LCD command rcall lcdcmd ldi timeout,256;Delay 15 mS for clear command rcall delay ret ;========================================================================= ; Initialize LCD module ;========================================================================= lcdinit: ldi wreg,0 ;Setup port pins out PORTD,wreg;Pull all pins low ldi wreg,0xff;All pins are outputs out DDRD,wreg ldi timeout,256;Wait at least 15 mS at power up rcall delay ldi wreg,3 ;Function set out PORTD,wreg sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde ldi timeout,65;Wait at least 4.1 mS rcall delay ldi wreg,3 ;Function set out PORTD,wreg sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde ldi timeout,2;Wait at least 100 uS rcall delay ldi wreg,3 ;Function set out PORTD,wreg sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde ldi wreg,2 ;Function set, 4 line interface out PORTD,wreg sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde ldi wreg,0b11110000;Make 4 data lines inputs out DDRD,wreg ; At this point, the normal 4 wire command routine can be used ldi wreg,0b00100000;Function set, 4 wire, 2 line, 5x7 font rcall lcdcmd ldi wreg,0b00001100;Display on, cursor off, blink off rcall lcdcmd ldi wreg,0b00000110;Address increment, no scrolling rcall lcdcmd ret ; Wait for LCD to go unbusy lcdwait: ldi wreg,0xF0;Make 4 data lines inputs out DDRD,wreg sbi PORTD,lcdrw;Set r/w pin to read cbi PORTD,lcdrs;Set register select to command waitloop: sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde in lcdstat,PIND;Read busy flag sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde sbrc lcdstat,3;Loop until done rjmp waitloop ret ; Send command in wreg to LCD lcdcmd: mov test,wreg rcall lcdwait ldi wreg,0xFF out DDRD,wreg mov wreg,test mov test,wreg swap wreg andi wreg,0X0F out portD,wreg sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde mov wreg,test andi wreg,0x0F;Strip off upper bits out PORTD,wreg;Put on port sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde ldi wreg,0xF0;Make 4 data lines inputs out DDRD,wreg ret ; Send character data in wreg to LCD lcdput: mov test,wreg;Save character rcall lcdwait ;Wait for LCD to be ready ldi wreg,0xFF;Make all port D pins outputs out DDRD,wreg mov wreg,test;Get character back mov test,wreg;Save another copy swap wreg ;Get upper nibble andi wreg,0x0F;Strip off upper bits out PORTD,wreg;Put on port sbi PORTD,lcdrs;Register select set for data sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde mov wreg,test;Recall character andi wreg,0x0F;Strip off upper bits out PORTD,wreg;Put on port sbi PORTD,lcdrs;Register select set for data sbi PORTD,lcde;Toggle enable line cbi PORTD,lcde ldi wreg,0xF0;Make 4 data lines inputs out DDRD,wreg ret longdelay: ldi longtime,180; ldi timeout,256; puwait: rcall delay dec longtime brne puwait ret ;***** Delay n*64 microseconds using timer 0, delay time passed in timeout delay: ldi test,64 cagain: dec test brne cagain dec timeout brne delay ret ;========================================================================= loadbyte: ;========================================================================= lpm ; Load byte from program memory into r0 tst r0 ; Check if we've reached the end of the message breq return ; If so, quit mov wreg,r0 rcall lcdput ; Echo received char adiw ZL,1 ; Increase Z registers rjmp loadbyte return: ret ;return ;========================================================================= message1: .db "Press any key",0 message2: .db "please (1-16)",0 message3: .db "You pressed",0 message4: .db "key:",0 |