Negative & positive temperature measuring with ATMEGA32, LM35 & LCD [Full Code+Circuit Design]

The circuit design and output in Proteus:

(click here to download the Proteus design from git)

See the full output and coding from video tutorial (click here for the video) :

Components:

Codes:

Main C file:

#define F_CPU 8000000UL #include <avr/io.h> #include <stdio.h> #include <util/delay.h> #include "lcd.h" #include "adc.h" char line[16]; //int adc_value = 0; float adc_value1 = 0; float adc_value2 = 0; float adc_volt1 = 0; float adc_volt2 = 0; float mili_volt = 0; float t1 = 0; float t2 = 0; float temp = 0; int main(void) { LCDInit(); // declare lcd data port and control port /* Replace with your application code */ while (1) { LCDInit(); //Initialize LCD Display adc_init();//Function call sprintf(line,"ADC:"); LCDGotoXY(1,1); LCDString(line); sprintf(line,"Temp :"); LCDGotoXY(1,2); LCDString(line); while(1) { adc_value1 = adc_read(0); //ADC Read adc_value2 = adc_read(1); //ADC Read //adc_volt = ((adc_value*5)/1024.0); ref =5v //adc_volt = ((adc_value*2.56)/1024.0); //ref =2.56v adc_volt1 = ((adc_value1*2.56)/1024.0); // for all volt measurement. R1= 56K, R2=5K; adc_volt2 = ((adc_value2*2.56)/1024.0); // for all volt measurement. R1= 56K, R2=5K; //mili_volt = (adc_volt1 - adc_volt2)/1000; //temp = mili_volt/10; temp = (adc_volt1 - adc_volt2)*100; sprintf(line,"%.2f,%.2f",adc_value1,adc_value2); LCDGotoXY(5,1); LCDString(line); sprintf(line,"%.2f", temp); // 10 mili volt = 1 Centigrade LCDGotoXY(10,2); LCDString(line); //_delay_ms(50); } } }

adc.c (header file):

// 1. reference voltage selection // 2. prescaller seletion // 3. Enable adc // 4. channel selection // 5. adc data order // 6. start conversion // 7. read adc data #include <avr/io.h> #include "adc.h" void adc_init(void) { /* ADMUX |= (1<<REFS0); // For Aref=AVcc 5v ADMUX &= ~(1<<REFS1); // For Aref=AVcc 5v */ ADMUX |= (1<<REFS0); // For Aref=AVcc 2.56v ADMUX |= (1<<REFS1); // For Aref=AVcc 2.56v ADCSRA &= ~(1<<ADPS0); //Rrescalar div factor =64 - 011 ADCSRA |= (1<<ADEN)|(1<<ADPS2)|(1<<ADPS1); //Rrescalar div factor =64 - 011 } uint16_t adc_read(uint8_t ch) { //5 channel selection /* //channel 0 selection ADMUX &= ~(1<<MUX0); ADMUX &= ~(1<<MUX1); ADMUX &= ~(1<<MUX2); ADMUX &= ~(1<<MUX3); */ //variable channel selection ADMUX = ((1<<REFS0)|(1<<REFS1)|ch); // variable ch and avcc reference 2.56 //6. start conversion ADCSRA |= (1<<ADSC); while (bit_is_set(ADCSRA,ADSC)); //read adc data return ADCW; }

adc.h (header file):

/* * adc.h * * Created: 10/29/2017 8:23:27 AM * Author: Tajim */ //#ifndef ADC_H_ //#define ADC_H_ //#endif /* ADC_H_ */ void adc_init(void); uint16_t adc_read(uint8_t ch); //uint16_t adc_read(void);

lcd.c (header file):

#include "lcd.h" void LCDInit() { LCD_CONTROL_DIRECTION |= (1<<LCD_RS); //Set DDRC_Of_RS as OUTPUT Pin. LCD_CONTROL_DIRECTION |= (1<<LCD_RW); //Set DDRC_Of_RW as OUTPUT Pin. LCD_CONTROL_DIRECTION |= (1<<LCD_E); //Set DDRC_Of_E as OUTPUT Pin. LCD_DATA_DIRECTION |= (1<<LCD_D4); //Set DDRC_Of_D4 as OUTPUT Pin. LCD_DATA_DIRECTION |= (1<<LCD_D5); //Set DDRC_Of_D5 as OUTPUT Pin. LCD_DATA_DIRECTION |= (1<<LCD_D6); //Set DDRC_Of_D6 as OUTPUT Pin. LCD_DATA_DIRECTION |= (1<<LCD_D7); //Set DDRC_Of_D7 as OUTPUT Pin. LCD_CONTROL_PORT &= ~(1<<LCD_RS); //PORT_Of_RS goes to LOW for Command Mode LCD_CONTROL_PORT &= ~(1<<LCD_E); //Clear of PORT_Of_E (Initialize stage is zero) _delay_ms(150); LCDSendCmd4BIT(0x03); // 8-bit data length (Repeat 3-times for clear lcd memory) _delay_ms(150); LCDSendCmd4BIT(0x03); // 8-bit data length (Repeat 3-times for clear lcd memory) _delay_ms(150); LCDSendCmd4BIT(0x03); // 8-bit data length (Repeat 3-times for clear lcd memory) _delay_ms(150); LCDSendCmd4BIT(0x02); //Set to 4 bit operation LCDSendCmd(0x28); //function set, 4 line, 8-bit, character size=5x7 //LCDClear(); //clear display (0x01) //LCDOff(); //turn off the LCD (0x08) LCDOn(); //turn on the LCD (0x0C) LCDSendCmd(0x06); //Sets mode to increment the address by one and to shift the cursor to the right at the time of write to the DD/CGRAM. LCDSendCmd(DDRAM_PTR); //set DDRAM Address (0x80) } void LCDGotoXY(unsigned char x,unsigned char y) { if(y == 1) { LCDSendCmd(DDRAM_PTR + LINE1_ADDR + x-1); } else if(y == 2) { LCDSendCmd(DDRAM_PTR + LINE2_ADDR + x-1); } else if(y == 3) { LCDSendCmd(DDRAM_PTR + LINE3_ADDR + x-1); } else if(y == 4) { LCDSendCmd(DDRAM_PTR + LINE4_ADDR + x-1); } } void LCDSendCmd(unsigned char ucCmd) { //LCD_RS=LCD_cmd; LCD_CONTROL_PORT &= ~(1<<LCD_RS); LCDSendCmd4BIT(ucCmd>>4); LCDSendCmd4BIT(ucCmd); } void LCDSendData (unsigned char ucData) { //LCD_RS=LCD_data; LCD_CONTROL_PORT |= (1<<LCD_RS); LCDSendCmd4BIT(ucData>>4); LCDSendCmd4BIT(ucData); } void LCDSendCmd4BIT(unsigned char ucCmd) { if(ucCmd&0x01) LCD_DATA_PORT |= (1<<LCD_D4); else LCD_DATA_PORT &= ~(1<<LCD_D4); if(ucCmd&0x02) LCD_DATA_PORT |= (1<<LCD_D5); else LCD_DATA_PORT &= ~(1<<LCD_D5); if(ucCmd&0x04) LCD_DATA_PORT |= (1<<LCD_D6); else LCD_DATA_PORT &= ~(1<<LCD_D6); if(ucCmd&0x08) LCD_DATA_PORT |= (1<<LCD_D7); else LCD_DATA_PORT &= ~(1<<LCD_D7); LCD_CONTROL_PORT |= (1<<LCD_E); LCD_CONTROL_PORT &= ~(1<<LCD_E); _delay_ms(2); } void LCDPutchar(char c) { LCDSendData(c); } void LCDString(char *msg) { uint8_t len = 0; while(*msg) { LCDPutchar(*msg); msg++; len++; } while(LCD_MAX_CHAR_IN_LINE - len) { LCDPutchar(0x20); // Space len++; } } void LCDShowCursor() { LCDSendCmd(0x0E); // Display on, Cursor On and Blink On; } void LCDHideCursor() { LCDSendCmd(0x0C); // Display on, Cursor Off and Blink Off; } void LCDRefresh() { //LCD_RS= LCD_cmd; LCD_CONTROL_PORT &= ~(1<<LCD_RS); //LCD_E = LCD_DISABLE; LCD_CONTROL_PORT &= ~(1<<LCD_E); _delay_ms(2); LCDSendCmd4BIT(0x03); _delay_ms(2); LCDSendCmd4BIT(0x03); _delay_ms(2); LCDSendCmd4BIT(0x03); _delay_ms(2); LCDSendCmd4BIT(0x02); _delay_ms(2); LCDSendCmd(0x28); //function set, 4 line, 8-bit, character size=5x7 LCDSendCmd(0x02 ); LCDOn(); //turn on the LCD LCDSendCmd(0x06); LCDSendCmd(DDRAM_PTR); //set DDRAM Address }

lcd.h (header file):

#define F_CPU 8000000UL #include <avr/io.h> // include I/O definitions (port names, pin names, etc) #include <util/delay.h> #define LCD_CONTROL_PORT PORTD #define LCD_CONTROL_DIRECTION DDRD #define LCD_DATA_PORT PORTC #define LCD_DATA_DIRECTION DDRC #define LCD_RS 4 //LCD PIN 4 #define LCD_RW 5 //LCD PIN 5 connect to GND. #define LCD_E 6 //LCD PIN 6 #define LCD_D4 4 //LCD PIN 11 #define LCD_D5 5 //LCD PIN 12 #define LCD_D6 6 //LCD PIN 13 #define LCD_D7 7 //LCD PIN 14 #define LCD_MAX_CHAR_IN_LINE 20 #define LCD_cmd 0 //RS=0 for command mode. #define LCD_data 1 //RS=1 for command mode. #define LCD_ENABLE 1 //LCD Enable(E) set 0-to-1 for executing the current instruction #define LCD_DISABLE 0 //LCD Enable(E) set 0-to-1 for executing the current instruction //Entry modes, use at initialization #define LCD_CURSOR_SHIFT_LEFT_MODE 0x04// 0000 0100 #define LCD_DISPLAY_SHIFT_LEFT_MODE 0x05// 0000 0101 #define LCD_CURSOR_SHIFT_RIGHT_MODE 0x06// 0000 0110 #define LCD_DISPLAY_SHIFT_RIGHT_MODE 0x07// 0000 0111 //DDRAM Addresses #define DDRAM_PTR 0x80 // Address Display Data RAM pointer #define LINE1_ADDR 0x00 // Start of line 1 in the DD-Ram #define LINE2_ADDR 0x40 // Start of line 2 in the DD-Ram #define LINE3_ADDR 0x14 // Start of line 3 in the DD-Ram #define LINE4_ADDR 0x54 // Start of line 4 in the DD-Ram //Display modes, use at initialization #define LCDOff() LCDSendCmd(0x08) #define LCDOn() LCDSendCmd(0x0C) #define LCDCursorOff() LCDSendCmd(0x0C) #define LCDCursorNoBlink() LCDSendCmd(0x0E) #define LCDCursorBlink() LCDSendCmd(0x0F) #define LCDClear() LCDSendCmd(0x01); _delay_ms(10) #define LCDCursorHome() LCDSendCmd(0x02) #define LCDCursorLeft() LCDSendCmd(0x10) #define LCDCursorRight() LCDSendCmd(0x14) #define LCDDisplayShiftLeft() LCDSendCmd(0x1C) #define LCDDisplayShiftRight() LCDSendCmd(0x18) void LCDSendCmd4BIT(unsigned char ucCmd); void LCDSendCmd(unsigned char ucCmd); void LCDSendData (unsigned char ucData); void LCDGotoXY(unsigned char x,unsigned char y); void LCDInit(void); void LCDString(char *msg); void LCDShowCursor(void); void LCDHideCursor(void); void LCDRefresh(void); void LCDPutchar(char c);  
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To get Full code and Proteus file from my git click here: 

https://gitlab.com/tajimiitju/Programming_by_tajim/tree/master/Microcontroller_program_by_tajim/Negative%20and%20positive%20temperature%20mesuring%20with%20ATMEGA32%20with%20LM35%20and%20LCD
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