ENQ empfang testen

void uart_putchar(char c)

{

  // Warten bis Buffer bereit ...

  while (!(UCSRA & (1 << UDRE)));

  // Senden...

  UDR = c;

  _delay_ms(10);  

}

char uart_getchar()

{

  // Ist schon ein Zeichen im Buffer?

  while( !(UCSRA & (1<<RXC)) );

   return UDR;  

}

int main(void)

{

  char kommando; 

  // RS232 einschalten ... 

  setup_uart();

  DDRB = 0xFF;

  //sendet Anforderung (ENQ)

  uart_putchar('E');    

  kommando = uart_getchar(); 

  if (kommando='F')   

     PORTB = 0x0F;

  else

     PORTB = 0x55;

  return0;

//sendet Anforderung (ENQ)

uart_putchar(0x05);

response = uart_getchar(); 

if (response == 0x06) {

   // irgendwas machen was eben gemacht werden soll wenn die cam ACK gesendet hat

}

void uart_putchar(char c)

{

  // Warten bis Buffer bereit ...

  while (!(UCSRA & (1 << UDRE)));

  // Senden...

  UDR = c;

  _delay_ms(10);  

}

char uart_getchar()

{

  // Ist schon ein Zeichen im Buffer?

  while( !(UCSRA & (1<<RXC)) );

   return UDR;  

}

int main(void)

{

  char kommando; 

  // RS232 einschalten ... 

  setup_uart();

  DDRB = 0xFF;

  //sendet Anforderung (ENQ)

  uart_putchar(0x05);    

  kommando = uart_getchar(); 

  if (kommando=0x06)   

     PORTB = 0x0F;

  else

     PORTB = 0x55;

  return0;

if (kommando == 0x06)   

     PORTB = 0x0F;

  else

     PORTB = 0x55;

void initall()

{

  setup_uart(); 

  //interrupt

  TCNT0 = 5;        //Set Timer/counter

  TIMSK |= (1<<TOIE0);  //Enable Timer/counter0 overflow interrupt

  TCCR0 |= (1<<CS01);

  TCCR0 |= (1<<CS00);  //Select the clock source to be used by the timer/counter --> CPU Takt  --> 4MHz/64 

  TIFR |= (1<<TOV0);  //interrupt starts with each overflow   

}//End initall()

//Interrupt Service Routine 

ISR(TIMER0_OVF_vect) 

{

  ADIteiler++;    //clocks interrupt counter value on each ms 

  if(ADIteiler >= 60)  //Counter cycle for all ms 60

  {

    ADIteiler=0;    //counter 0 set

    DDRB = 0xFF;

    char kommando;

    kommando = uart_getchar(); 

    if (kommando == 0x06)

      PORTB = 0x0F;

   else

      PORTB = 0x55;  

 }

}//End ISR(TIMER0_OVF_vect) 

int main(void) 

{

    initall();

    //sendet Anforderung (ENQ)

    uart_putchar(0x05);

    sei();

    return 0;                     

} //end main()

PC  <---------------->  PC

PC  <--Pegelwandler-->  AVR

AVR <---------------->  Cam

PC  <--Pegelwandler-->  Cam

#ifndef F_CPU

/* In the new version of the WinAVR/Mfile Makefile guideline One can defined F_CPU in the Makefile, a repeated 

   definition here would lead to a compiler warning . therefore "prevention" through    #ifndef/#endif

   This "Prevention" can lead to Debugger, if AVRStudio use a another, not the hardware fitting Clock rate: 

   Then the    following definition doesn't use, but instead the default value (1 MHz?) of AVRStudio - hence 

   the Output of a warning if F_CPU yet does not define:*/ 

#warning "F_CPU was not defined yet, now make up with 4000000"

#define F_CPU 4000000L                  // Systemtakt in Hz - define as  long>> Without errors in the computation 

#endif

#define BAUD 9600L

#define UBRR_VAL ((F_CPU+BAUD * 8)/(BAUD*16)-1)     //clever round

#define BAUD_REAL (F_CPU/(16*(UBRR_VAL+1)))         //real baud rate

#define BAUD_ERROR ((BAUD_REAL*1000)/BAUD-1000)     //Error per thousand

#if ((BAUD_ERROR>10)||(BAUD_ERROR<-10))

#error Systematic error in the baud rate more than 1% and thus too high!

#endif

#include <avr/io.h>

#include <stdlib.h>

#include <inttypes.h>

#include <util/delay.h>

void USART_Init(void) 

{

  UBRRH = (unsigned char)(UBRR_VAL>>8);      // Set baud rate

  UBRRL = (unsigned char)UBRR_VAL;

  UCSRB |= (1<<RXEN)|(1<<TXEN);          // Enable receiver and transmitter

  UCSRC = (1<<URSEL) | (1<<UCSZ0)|(1<<UCSZ1);  // Set frame format: 8data, 1stop bit        

}//end USART_Init()

void USART_Putc(unsigned char c)

{

    while (!(UCSRA & (1<<UDRE))); // Do nothing until data have been transmited 

  UDR = c;                      // Put data into Buffer, sends the data

  _delay_ms(10);   

}//end USART_Putc()

void USART_Puts (char *string)

{

    while( *string != '\0' )  //as long as *string != '\0' so unlike the "stringer end-character"

    {  

        USART_Putc(*string);

        string++;

    }

}//end USART_Puts()

unsigned char USART_Receive()

{