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/*
* $Id$
*/
#include <avr/io.h>
#include <stdlib.h>
//include <sig-avr.h>
#include <avr/interrupt.h>
#include "serial.h"
#include "StdDefs.h"
// 02-Sep-2008 K. Schwichtenberg Clearing of UDRIE corrected
#define ESC 0x1b
#define BUFF_SIZE 64
unsigned char CLR[] = {ESC, '[','H', ESC, '[', '2', 'J',0};
unsigned char UART_buffer[BUFF_SIZE];
unsigned char *inptr, *outptr;
unsigned char buff_cnt;
void init_uart(void)
{
inptr = UART_buffer;
outptr = UART_buffer;
buff_cnt = 0;
}
void clr(void)
{
//putstr(CLR); // Send a 'clear screen' to a VT100 terminal
}
int putchar(int c)
{
if (buff_cnt<BUFF_SIZE)
{
*inptr = c; // Put character into buffer
inptr++; // Increment pointer
buff_cnt++;
if (inptr >= UART_buffer + BUFF_SIZE) // Pointer wrapping
inptr = UART_buffer;
UART_CONTROL_REG = 0x38; // Enable UART Data register
// empty interrupt
return 1;
} else {
return 0; // Buffer is full
}
}
// Interrupt driven transmitter
SIGNAL(UART_REG_EMPTY_INT_VECTOR)
{
UART_DATA_REG = *outptr; // Send next byte
outptr++; // Increment pointer
if (outptr >= UART_buffer + BUFF_SIZE) // Pointer wrapping
outptr = UART_buffer;
if(--buff_cnt == 0) // If buffer is empty:
// UART_CONTROL_REG = UART_CONTROL_REG && (1<<UDRIE); // disable interrupt This was Atmels original
UART_CONTROL_REG = UART_CONTROL_REG & (~(1<<UDRIE)); // disable interrupt This is what they meant K.Schwi
}
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