suraksha s
Newbie level 5
sir this is our program to display adc_ppm value on LCD using ATMEGA32 microcontroller we are facing problem in displaying converted value the result is in symbol form not in any value plz help me out as soon as possible
Code:
#include <avr/io.h>
#define F_CPU 8000000
#include<util/delay.h>
#define LCD_DATA PORTC // LCD data port
#define ctrl PORTA
#define en PA6 // enable signal
#define rw PA5 // read/write signal
#define rs PA4 // register select signal
void LCD_cmd(unsigned char cmd);
void LCD_init(void); // initialization of LCD
void LCD_write_data(unsigned int data); //Single Character Display
void LCD_send_string(char *string); //Character Array Display
void ADC_init(void); //initialization of ADC
unsigned int ADC_StartConversion(unsigned int channel);//function of ADC
void LCD_read_data(unsigned int data);
int main(void)
{
unsigned int adc_result,adc_ppm;
DDRC=0xFF; // Port C as output port
DDRB=0xFF; // Port B as output port
DDRA=(1<<PA6)|(1<<PA5)|(1<<PA4); // making PORTA pins 4,5,6 as output for LCD
PORTC=0x00; // Clearing Port C
MCUCSR|=(1<<JTD); // sending 1 to JTD to disable JTAG interface with Port C
MCUCSR|=(1<<JTD);
ADC_init(); //initialization of ADC
_delay_ms(10);
LCD_init(); // initialization of LCD
_delay_ms(2); // delay of 1 milli seconds
LCD_cmd(0x80); //cursor on the 1st line
_delay_ms(2);
LCD_send_string("CO Level:"); // Display "CO level" on first line
_delay_ms(2);
while (1)
{
adc_result=ADC_StartConversion(0); //Get the adc value of channel zero
adc_ppm=(adc_result/20); /*since 1ppm=20counts the adc_result is divided by 20
inorder to get the CO ppm Value*/
LCD_cmd(0x89); //cursor on 1st line 10th position
_delay_ms(10);
LCD_write_data(adc_ppm); //sending ppm value to LCD
LCD_cmd(0x8C); //cursor on 1st line 13th position
_delay_ms(2);
LCD_send_string("PPM"); //Displaying PPM "the unit" of gas to LCD
if(adc_ppm<=20)
{
LCD_cmd(0xC7); //cursor on the 2nd line 7th position
_delay_ms(2);
LCD_send_string(" SAFE "); //displays SAFE when ppm value is <20
PORTB=0x00;
_delay_ms(500);
PORTB=0x01;
_delay_ms(500);
}
else if(adc_ppm>20)
{
LCD_cmd(0xC6); //cursor on the 2nd line 6th position
_delay_ms(2);
LCD_send_string(" DANGER "); //displays DANGER when ppm value is >20
PORTB=0x00;
_delay_ms(500);
PORTB=0x02;
_delay_ms(500);
}
}
return 0;
}
void LCD_send_string(char *string) //Character Array Display
{
while(*string)
{
LCD_DATA= *string;
ctrl = (1<<rs)|(0<<rw)|(1<<en); // RW as LOW and RS, EN as HIGH
_delay_ms(2);
ctrl = (1<<rs)|(0<<rw)|(0<<en); // EN and RW as LOW and RS HIGH
_delay_ms(2); // delay to get things executed
string++;
}
}
void LCD_init(void) // initialization of 16X2 LCD in 8bit mode
{
LCD_cmd(0x38);
_delay_ms(2);
LCD_cmd(0x01); // Clear Display, Cursor to Home
_delay_ms(2);
LCD_cmd(0x0E); // Display, Cursor, and Cursor Blink OFF
_delay_ms(2);
LCD_cmd(0x80); // ---8 go to first line and --0 is for 0th position
_delay_ms(2);
return;
}
void LCD_cmd(unsigned char cmd)
{
LCD_DATA=cmd;
ctrl =(0<<rs)|(0<<rw)|(1<<en); // RS and RW as LOW and EN as HIGH
_delay_ms(2);
ctrl =(0<<rs)|(0<<rw)|(0<<en); // RS, RW , LOW and EN as LOW
_delay_ms(2);
return;
}
void LCD_write_data(unsigned int data) //Single Character Display
{
LCD_DATA= data;
ctrl = (1<<rs)|(0<<rw)|(1<<en); // RW as LOW and RS, EN as HIGH
_delay_ms(2);
ctrl = (1<<rs)|(0<<rw)|(0<<en); // EN and RW as LOW and RS HIGH
_delay_ms(2); // delay to get things execute
return;
}
void LCD_read_data(unsigned int data) //Single Character Display
{
LCD_DATA= data;
ctrl = (1<<rs)|(1<<rw)|(1<<en); // RW as LOW and RS, EN as HIGH
_delay_ms(2);
ctrl = (1<<rs)|(1<<rw)|(0<<en); // EN and RW as LOW and RS HIGH
_delay_ms(2); // delay to get things execute
return;
}
void ADC_init() //initialization of ADC
{
ADCSRA=0x82; //Enable ADC , sampling freq=osc_freq/64
_delay_ms(10);
ADMUX=0x40; //Result right justified, select channel zero
}
unsigned int ADC_StartConversion(unsigned int channel)
{
ADMUX=channel; //Select a channel
_delay_ms(10); //Wait till the channel is selected
ADCSRA|=(1<<ADSC); //Start the ADC conversion by setting bits for ADEN, ADSC, Prescaler to /64
while((ADCSRA & (1<<ADIF))==0); //Wait till the conversion is over
//ADIF will be set once ADC conversion is complete
return(ADC); //Return the 10-bit result
}
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