mirror of
https://github.com/binary-kitchen/doorlockd
synced 2024-12-22 10:24:26 +01:00
54 lines
936 B
C
54 lines
936 B
C
#include <stddef.h>
|
|
#include <avr/interrupt.h>
|
|
#include <avr/io.h>
|
|
|
|
#include "uart.h"
|
|
|
|
#define UBRR_VAL ((F_CPU+BAUD*8)/(BAUD*16)-1)
|
|
#define BAUD_REAL (F_CPU/(16*(UBRR_VAL+1)))
|
|
#define BAUD_ERROR ((BAUD_REAL*1000)/BAUD)
|
|
|
|
#if ((BAUD_ERROR<990) || (BAUD_ERROR>1010))
|
|
#error Choose another crystal. Baud error too high.
|
|
#endif
|
|
|
|
static void (*recv_handler)(unsigned char c) = NULL;
|
|
|
|
ISR(USART_RX_vect)
|
|
{
|
|
cli();
|
|
if(recv_handler)
|
|
recv_handler(UDR);
|
|
sei();
|
|
}
|
|
|
|
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);
|
|
}
|