#define F_CPU 16000000UL
#define sbi(PORTX,bitX) PORTX|=(1<<bitX)
#define cbi(PORTX,bitX) PORTX&=~(1<<bitX)

#include <mega128.h>
#include <delay.h>
#include <stdio.h>

void LCD_init(void);
void LCD_data(char data);
void LCD_command(char command);
void LCD_string(char line, char *string);
int Adc_Channel(char Adc_input);
void USART_Transmit(char data);
void USART_Transmit_int(int data);

char buf[16] = {‘ ‘,};
int adc_data = 0;
int cnt_ms = 0;
float cnt_s = 0.000;
float cnt_m = 0.000;
float cnt_data = 0.000;
float bpm = 0.000;
int bef_flag = 0;
int flag = 0;
int tick = 0;
int tick_flag = 0;

void main()
{
// io 핀 설정
DDRA = 0xFF;
DDRB = 0xFF;
DDRC = 0xFF;
PORTA = 0×00;
PORTB = 0×00;
PORTC = 0×00;

// ADC
ADMUX = 0×00;
ADCSRA = (1<<ADEN)|(1<<ADSC)|(1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0);

// TIMER/COUNTER
TCCR0 = (1<<CS02)|(1<<CS00); // 128분주
TCNT0 = 256-125; // 125번 => 0.001s
TIMSK = (1<<TOIE0);

// UART
UCSR1A = 0×00;
UCSR1B = (1<<TXEN1);
UCSR1C = (1<<UCSZ11)|(1<<UCSZ10); //8bit
UBRR1H = 0;
UBRR1L = 103;

// LCD
LCD_init();
LCD_string(1,” BPM “);

#asm(“sei”)

// 동작 시작 부저 알림 “삡,삡”
sbi(PORTC,0);
delay_ms(100);
cbi(PORTC,0);
delay_ms(300);
sbi(PORTC,0);
delay_ms(100);
cbi(PORTC,0);

while(1)
{

adc_data = Adc_Channel(0);
bef_flag = flag;

if(adc_data > 500) // 기준치 보다 전압 신호 크면
{
sbi(PORTB,1);
flag = 1;
}

else
{
cbi(PORTB,1);
flag = 0;
}

if((bef_flag == 0) && (flag == 1)) // 기준치 보다 전압신호 높아지는 순간
{
cnt_data = (float)cnt_ms; // 카운트된 값 저장 . 심박 신호간 길이 (밀리초)
cnt_ms = 0;

cnt_s = cnt_data/1000; // 심박 신호간 길이 (초)
cnt_m = cnt_s/60; // 심박 신호간 길이 (분)
bpm = 1/cnt_m; // 분당 심박수 (주기와 주파수는 역수관계)
}

if(tick_flag == 1) // 2초에 한번 동작 하는 곳
{
//LCD 표시
sprintf(buf, ” %4d “,(int)bpm);
LCD_string(2,buf);

//블루투스 전송
USART_Transmit_int(bpm);
USART_Transmit(0);
//부저 동작
if ((bpm < 50) || (bpm > 180)) // 이상 BPM
{
sbi(PORTC,0);
USART_Transmit(‘ ‘);
USART_Transmit(‘W’);
USART_Transmit(‘A’);
USART_Transmit(‘R’);
USART_Transmit(‘N’);

USART_Transmit(‘ ‘);
USART_Transmit(‘S’);
USART_Transmit(‘T’);
USART_Transmit(‘A’);
USART_Transmit(‘T’);
USART_Transmit(‘E’);
}
else
cbi(PORTC,0);

tick_flag = 0;
}
}
}

interrupt [TIM0_OVF] void timer0_ovf_isr(void)
{
cnt_ms ++; // 0.001s 1씩 증가

tick ++;
if(tick >= 2000)
{
tick = 0;
tick_flag = 1;
}

TCNT0 = 256-125;
}

int Adc_Channel(char Adc_input)
{
ADMUX = 0b01000000 | Adc_input;
ADCSRA |= 0×40;
while((ADCSRA & 0×10) == 0);
return ADCW;
}

void LCD_command(char command)
{
PORTA = (command&0xF0); // send High data
cbi(PORTA,0); // RS=0
//cbi(PORTA,1); // RW=0
sbi(PORTA,2); // Enable
delay_us(1);
cbi(PORTA,2); // Disable

PORTA = (command&0x0F)<<4; // send Low data
cbi(PORTA,0); // RS=0
//cbi(PORTA,1); // RW=0
sbi(PORTA,2); // Enable
delay_us(1);
cbi(PORTA,2); // Disable
}

void LCD_data(char data)
{
delay_us(100);

PORTA = (data&0xF0); // send High data
sbi(PORTA,0); // RS=1
//cbi(PORTA,1); // RW=0
sbi(PORTA,2); // Enable
delay_us(1);
cbi(PORTA,2); // Disable

PORTA = (data&0x0F)<<4; // send Low data
sbi(PORTA,0); // RS=1
//cbi(PORTA,1); // RW=0
sbi(PORTA,2); // Enable
delay_us(1);
cbi(PORTA,2); // Disable
}

void LCD_init(void)
{
delay_ms(50);

LCD_command(0×28); // DL=0(4bit) N=1(2Line) F=0(5×7)
delay_ms(2); // [function set] 0b00101000
// 4:(DL) 1이면 8bit모드, 0이면 4bit모드
// 3:(N) 0이면 1줄짜리, 1이면 2줄짜리
// 2:(F) 0이면 5x8dots, 1이면 5x11dots

LCD_command(0x0C); // LCD ON, Cursor X, Blink X
delay_ms(2); // [display on/off control] 0b00001100
// 2:(D) 1이면 display on, 0이면 off
// 1:(C) 1이면 cursor on, 0이면 off
// 0:(B) 1이면 cursor blink, 0이면 off

LCD_command(0×06); // Entry Mode
delay_ms(2); // [entry mode set] 0b00000110
// 1:(I/D) 1이면 오른쪽으로, 0이면 왼쪽
// 0:(SH) CGRAM 사용관련

LCD_command(0×01); // LCD Clear
delay_ms(2);
}
void LCD_string(char line, char *string)
{
LCD_command(0×80+((line-1)*0×40));
while(*string)
LCD_data(*string++);
}

void USART_Transmit(char data)
{
while(!(UCSR1A & 0×20));
UDR1 = data;
}

void USART_Transmit_int(int data)
{
int temp;

if(data < 10)
{
temp = data;
USART_Transmit(temp+48);
}
else if(data < 100)
{
temp = data/10;
USART_Transmit(temp+48);
temp = (data%10)/1;
USART_Transmit(temp+48);
}
else if(data < 1000)
{
temp = (data%1000)/100;
USART_Transmit(temp+48);
temp = (data%100)/10;
USART_Transmit(temp+48);
temp = (data%10)/1;
USART_Transmit(temp+48);
}
else
{
temp = data/1000;
USART_Transmit(temp+48);
temp = (data%1000)/100;
USART_Transmit(temp+48);
temp = (data%100)/10;
USART_Transmit(temp+48);
temp = (data%10)/1;
USART_Transmit(temp+48);
}
}