thinking about changing it up

avrserial.c

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

#define BAUD 19200
#define important_magic_number F_CPU/16/BAUD-1

int32_t main{
  begin(important_magic_number);
  /* need to figure out which ports /registers/pins to use*/

void begin( uint16_t ubrr) {
  /* set bit transfer rate */
  UBRRH = (uint8_t)(ubrr>>8);
  UBRRL = (uint8_t)ubrr;
  /*i hope this is right for tx/rx */
  UCSRB = (1<<RXEN)|(1<<TXEN);
  UCSRC = (1<<URSEL)|(3<<UCSZ0);  
  /*frame: 8data  one stop bit [?parity?]*/
}

void put_char(int8_t data) {
  /* evidently there is some kind of buffer  */
  while ( !(UCSRA & (_BV(UDRE))) );
  UDR = data; /*---- put! ---*/

}
char get_char(void) {
  /* we learned this in k&r */
  while ( !(UCSRA & (_BV(RXC))) );
  return UDR;   /*----  get!  ---*/
}
void put_string(int8_t *c) {
    while (*c) { 
        put_char(*c);
        c++;
    }
}