#include <stdint.h>
#include <stdio.h>
#include <avr/interrupt.h> 

//uart

#define MAX_BUFF 64   // 
#define PORT_TxD PORTA
#define PIN_TxD PA7
#define DDR_TxD DDRA


volatile uint8_t buffer[MAX_BUFF];
volatile uint8_t buffer_anfang;
volatile uint8_t buffer_ende;
volatile uint8_t bit_counter;
volatile uint16_t U_measure_in,U_measure_out, I_measure;

volatile uint16_t sec;


uint8_t put_char(uint8_t c)
{
	
	if(((buffer_ende+1)==buffer_anfang)||((buffer_anfang==0)&&(buffer_ende==(MAX_BUFF-1)))) return 0;
	buffer_ende++;
	if (buffer_ende==(MAX_BUFF)) buffer_ende=0;
	buffer[buffer_ende]=c;
	return 1;
}



ISR(ADC_vect)
{
	static uint8_t bit;

	static uint16_t c;
	
	ADMUX = 0b10000000;             // Kanal waehlen
	U_measure_in = ADC;  // ADCW muss einmal gelesen werden,

	ADMUX = 0b10000001;                      // Kanal waehlen
	U_measure_out = ADC;  // ADCW muss einmal gelesen werden,

    ADMUX = 0b10001000;
	I_measure = ADC;
	
	if(bit) PORT_TxD &= ~(1<< PIN_TxD); //TXD
	else PORT_TxD |= 1<< PIN_TxD;	

//	PORTA^= 1<<PA7; //Toggeln messen AN RS232

	if(bit_counter)
	{
		bit_counter--;

		bit= buffer[buffer_anfang]&1;
		buffer[buffer_anfang] = buffer[buffer_anfang]>>1;

		if(bit_counter<=1) bit=1;
	
	}
	else
	{
		if(buffer_anfang!=buffer_ende)
		{
			bit_counter=10;
			bit=0;
			buffer_anfang++;
			if (buffer_anfang==(MAX_BUFF)) buffer_anfang=0;
		
		}
	}
	
	

/*	I_measure = ADC;

	c++;
	if(c==9600)
	{
		c=0;
		sec++;
	
	}*/
 
}



uint8_t uart_ready(void)
{

	return ((buffer_ende==buffer_anfang)&&(!bit_counter));
}




void init_uart(void)
{
	cli();

	U_measure_in = 0;
	U_measure_out = 0;
	I_measure = 0;

	//ADMUX = (1<<REFS1); // interne Referenzspannung nutzen
	

	ADCSRA=  1<<ADEN | 1<<ADSC |1<<ADATE | 1<<ADIE | 1<<ADPS2 | 1<<ADPS1;    // wandler ein interrupt teiler64
	
	ADCSRB=0; //Atuo Trigger running conversion

		
	DDR_TxD |= 1<<PIN_TxD;
	buffer_anfang=0;
  	buffer_ende=0;

	//sei();

}


void int_put(const char *s)
/* print string on RS232 (no auto linefeed) */
{
    register  char c;

    while ( (c = *s++) ) {
        put_char(c);
    }

}/* int_put */


int main(void)
{
	
	OSCCAL = 0x74; //interner Ozsillatorfrequenz auf 8Mhz einstellen Seite 

	char cbuf[6], cbuf2[6], cbuf3[6];

	DIDR0 =0x0f;
	init_uart();
	
	sei();
	
	while(1)
	{
	//	sec=0;
		
		

		itoa(U_measure_in, cbuf,10);
		itoa(U_measure_out, cbuf2,10);
		itoa(I_measure, cbuf3,10);

	
		int_put(cbuf);
		put_char('S');
		put_char(13);
		put_char(10);
		
		int_put(cbuf2);
		put_char('E');
		put_char(10);
		put_char(13);

		int_put(cbuf3);
		put_char('V');
		put_char(10);
		put_char(13);
		
		while(!uart_ready());


	//	while(sec<2);
		

	

	}	
		
	
}