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/* uart.c -- routines for manipulating the ATmega16 UART.
Copyright (C) 2008 Ajith Kumar, Inter-University Accelerator Centre,
New Delhi and Pramode C.E, GnuVision.com.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
*/
#include <avr/io.h>
#define CPU_CLOCK 8000000 // 8 MHz clock is assumed
#define COMPUTE_BAUD(b) ((uint32_t)(CPU_CLOCK)/((uint32_t)(b)*16) - 1)
//Initialise UART: format 8 data bits, No parity, 1 stop bit
void uart_init(uint32_t baud)
{
UCSRB = (1 << TXEN) | (1 << RXEN);
UBRRH = (COMPUTE_BAUD(baud) >> 8) & 0xff;
UBRRL = (COMPUTE_BAUD(baud)) & 0xff;
UCSRC = (1 << URSEL) | (1 << UCSZ1) | (1 << UCSZ0);
}
uint8_t uart_recv_byte(void)
{
while( !(UCSRA & (1 <<RXC)) );
return UDR;
}
void uart_send_byte(uint8_t c)
{
while( !(UCSRA & (1 <<UDRE) ) );
UDR = c;
}
void uart_send_string(char *s){
while(*s!='\0'){
uart_send_byte(*(s++));
}
}
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