ADC stuff

/*
 * ATmega32L_ADC_test.c
 *
 * Created: 03.12.2011 18:53:45
 *  Author: Sabesto
 */

#define F_CPU 8000000UL
#define USART_BAUDRATE 9600
#define BAUD_PRESCALE (((F_CPU / (USART_BAUDRATE * 16UL))) - 1)

#include <avr/io.h>
#include <util/delay.h>
#include <avr/interrupt.h>

volatile uint8_t newSampleReady = 0;
volatile uint8_t channel = 0;
volatile uint8_t ad[7];


void uartinit (void)
{
    UCSRB |= (1 << RXEN) | (1 << TXEN);
    UCSRC |= (1 << UCSZ0) | (1 << UCSZ1);
    UBRRH = (BAUD_PRESCALE >> 8);
    UBRRL = BAUD_PRESCALE;
}
void USART1_Transmit(unsigned char data)
{
   while (!(UCSRA & (1<<UDRE)));
   UDR = data;
}
void USART1_TransmitString (const char *str) {

    while (*str)
    {
        USART1_Transmit(*str);
        str++;
    }
}

void adcinit (void){
    ADCSRA |= (1 << ADPS2) | (1 << ADPS1); // | (1 << ADPS0); // Set ADC prescalar to 64(128) - 125KHz sample rate @ 16MHz
    ADMUX = 0b01100000;
    //ADMUX |= (1 << REFS0); // Set ADC reference to AVCC
    //ADMUX |= (1 << ADLAR); // Left adjust ADC result to allow easy 8 bit reading
    ADCSRA |= (1 << ADATE);  // Set ADC to Free-Running Mode
    ADCSRA |= (1 << ADEN);  // Enable ADC
    ADCSRA |= (1 << ADIE);  // enable adc interrupt
    ADCSRA |= (1 << ADSC);  // Start A2D Conversions

}
int main (void)
{
    uartinit();
    adcinit();
    sei();
    while(1)
    {
        if (newSampleReady == 1)
        {
            for (uint8_t x = 0;x<7;x++)
            {
                USART1_Transmit(ad[x]);
                _delay_ms(100);
            }
        _delay_ms(4000);
        newSampleReady = 0;
        ADCSRA |= (1<<ADIE);
        }

    }
}

ISR(ADC_vect)
{
    ad[channel] = ADCH; // Store the result (8-bits, discard the 3 LSB)
    // ADCSRA &= ~(1 << ADEN); // Disable the ADC
    channel ++;


    if (channel == 7)
    {
        ADCSRA &= ~(1<<ADIE);
        // disable interrupts for now
        newSampleReady = 1; // 7 channels sampled
        channel = 0; // Reset to channel 0
    }
    ADMUX &= 0xE0;//Update the ADMUX register
    ADMUX |= channel;
}