mega16 test board test code 1-serial port test program

/**********Serial port definition**********/
#define RxD PD0
#define TxD PD1

#define baudrate 9600 //Baud rate
#define F_CPU 8000000UL //Define crystal frequency

void uart_init(void)
{
  /*****RS232 port line settings*****/
  PORTD|=BIT(RxD)|BIT(TxD);
  DDRD&=~BIT(RxD);
  DDRD|=BIT(TxD);
  
  /* Set baud rate*/
  UBRRL=(F_CPU/baudrate/16-1)%256; //This setting does not double the baud rate and U2X=0
  UBRRH=(F_CPU/baudrate/16-1)/256;
  /* Receiver and transmitter enable*/
  UCSRB|=BIT(4)|BIT(3);  
  /* Set transmission format*/
  //Asynchronous, 8-bit data, no parity, one stop bit, no speed
  UCSRC|=BIT(7)|BIT(2)|BIT(1);  
}

//Serial port data transmission, query method
void putc(unsigned char c)
{
   /* Wait for the transmission buffer to be empty*/
   while (!(UCSRA&(1<   /* Put the data into the buffer and send the data*/
   UDR = c;
}

//Serial string sending, query method
void puts(unsigned char *s)
{
  while(*s)
  {
   putc(*s);
   s++;
  }
  putc('\n');
  //return 1;
}

//Serial port data reception, query method
unsigned char getc(void)
{
  /* Wait for receiving data*/
  while (!(UCSRA&(1<   /* Get and return data from the buffer*/
  return UDR;
}

//Serial port receives data and stores it in an array
void get_s(unsigned char *js,unsigned int num)
{
 unsigned int i; 
   for(i=0;i    {
  js[i]=getc(); //Save data into the array
   }
}

//test.c

//ICC-AVR application builder : 2008-11-4 12:34:31
// Target : M16
// Crystal: 8.0000Mhz

#include
#include

#include "uart.h"

void main(void)
{
 uart_init();
 while(1)
 {
  putc(getc());
 }
}