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mirror of https://github.com/binary-kitchen/doorlockd synced 2024-12-22 18:34:25 +01:00
doorlockd-mirror/avr-code/uart.c
Ralf Ramsauer bd63a57d31 Cleanup AVR project, add new empty stubs
Signed-off-by: Ralf Ramsauer <ralf@binary-kitchen.de>
2018-09-03 21:28:41 +00:00

59 lines
1.1 KiB
C

/*
* doorlock-avr, AVR code of Binary Kitchen's doorlock
*
* Copyright (c) Binary Kitchen, 2018
*
* Authors:
* Ralf Ramsauer <ralf@binary-kitchen.de>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*/
#include <stddef.h>
#include <avr/interrupt.h>
#include <avr/io.h>
#include "uart.h"
#define UBRR_VAL ((F_OSC+UART_BAUD*8)/(UART_BAUD*16)-1)
#define BAUD_REAL (F_OSC/(16*(UBRR_VAL+1)))
#define BAUD_ERROR ((BAUD_REAL*1000)/UART_BAUD)
#if ((BAUD_ERROR<985) || (BAUD_ERROR>1010))
#warn BAUD_ERROR
#error Choose another crystal. Baud error too high.
#endif
static void (*recv_handler)(unsigned char c) = NULL;
void uart_init()
{
// Enable receive and transmit
UCSRB = (1<<RXEN)|(1<<TXEN)|(1<<RXCIE);
// Asynchronous mode, 8N1
UCSRC = (1<<UCSZ1)|(1<<UCSZ0);
UBRRH = UBRR_VAL >> 8;
UBRRL = UBRR_VAL & 0xFF;
}
void uart_set_recv_handler(void (*handler)(unsigned char c))
{
recv_handler = handler;
}
void uart_putc(const char c)
{
while ( !(UCSRA & (1<<UDRE)) );
UDR = (const unsigned char)c;
}
void uart_puts(const char* str)
{
do {
uart_putc(*str);
} while(*++str);
}