+/**
+ * \file
+ * <!--
+ * This file is part of BeRTOS.
+ *
+ * Bertos 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction. Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License. This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ *
+ * Copyright 2004, 2005 Develer S.r.l. (http://www.develer.com/)
+ * All Rights Reserved.
+ * -->
+ *
+ * \brief Simple serial I/O driver
+ *
+ * \version $Id$
+ * \author Francesco Sacchi <batt@develer.com>
+ */
+
+/*#*
+ *#* $Log$
+ *#* Revision 1.2 2006/07/19 12:56:26 bernie
+ *#* Convert to new Doxygen style.
+ *#*
+ *#* Revision 1.1 2005/04/12 01:37:50 bernie
+ *#* Import into DevLib.
+ *#*
+ *#* Revision 1.7 2005/01/23 12:24:27 bernie
+ *#* Include macros.h for BV().
+ *#*
+ *#* Revision 1.6 2004/10/20 13:40:54 batt
+ *#* Put {} instead of ; after while loop.
+ *#*
+ *#* Revision 1.5 2004/10/20 13:39:40 batt
+ *#* Reformat.
+ *#*
+ *#* Revision 1.4 2004/10/20 13:30:02 batt
+ *#* Optimization of UCSR0C writing
+ *#*
+ *#* Revision 1.3 2004/10/14 15:55:32 batt
+ *#* Add ser_purge.
+ *#*
+ *#* Revision 1.2 2004/10/14 14:46:59 batt
+ *#* Change baudrate calculation.
+ *#*
+ *#* Revision 1.1 2004/10/13 16:35:36 batt
+ *#* New (simple) serial driver.
+ *#*/
+#include "ser_simple.h"
+
+#include <compiler.h>
+#include <config.h>
+#include <macros.h> /* BV() */
+#include <hw.h>
+
+#include <avr/io.h>
+
+/**
+ * Send a character over the serial line.
+ *
+ * \return the character sent.
+ */
+int _ser_putchar(int c)
+{
+ /* Disable Rx to avoid echo*/
+ UCSR0B &= ~BV(RXEN);
+ /* Enable tx*/
+ UCSR0B |= BV(TXEN);
+ /* Prepare transmission */
+ UDR0 = c;
+ /* Wait until byte sent */
+ while (!(UCSR0A & BV(TXC))) {}
+ /* Disable tx to avoid short circuit when tx and rx share the same wire. */
+ UCSR0B &= ~BV(TXEN);
+ /* Enable Rx */
+ UCSR0B |= BV(RXEN);
+ /* Delete TRANSMIT_COMPLETE_BIT flag */
+ UCSR0A |= BV(TXC);
+ return c;
+}
+
+
+/**
+ * Get a character from the serial line.
+ * If ther is no character in the buffer this function wait until
+ * one is received (no timeout).
+ *
+ * \return the character received.
+ */
+int _ser_getchar(void)
+{
+ /* Wait for data */
+ while (!(UCSR0A & BV(RXC))) {}
+ return UDR0;
+
+}
+
+
+/**
+ * Get a character from the receiver buffer
+ * If the buffer is empty, ser_getchar_nowait() returns
+ * immediatly EOF.
+ */
+int _ser_getchar_nowait(void)
+{
+ if (!(UCSR0A & BV(RXC))) return EOF;
+ else return UDR0;
+}
+
+void _ser_settimeouts(void)
+{
+}
+
+/**
+ * Set the baudrate.
+ */
+void _ser_setbaudrate(unsigned long rate)
+{
+ /* Compute baud-rate period */
+ uint16_t period = (((CLOCK_FREQ / 16UL) + (rate / 2)) / rate) - 1;
+
+ UBRR0H = (period) >> 8;
+ UBRR0L = (period);
+}
+
+/**
+ * Send a string.
+ */
+int _ser_print(const char *s)
+{
+ while(*s) _ser_putchar(*s++);
+ return 0;
+}
+
+
+void _ser_setparity(int parity)
+{
+ /* Set the new parity */
+ UCSR0C |= (UCSR0C & ~(BV(UPM1) | BV(UPM0))) | (parity << UPM0);
+}
+
+/**
+ * Dummy functions.
+ */
+void _ser_purge(void)
+{
+ while (_ser_getchar_nowait() != EOF) {}
+}
+
+/**
+ * Initialize serial.
+ */
+struct Serial * _ser_open(void)
+{
+ /*
+ * Set Rx and Tx pins as input to avoid short
+ * circuit when serial is disabled.
+ */
+ DDRE &= ~(BV(PE0)|BV(PE1));
+ PORTE &= ~BV(PE0);
+ PORTE |= BV(PE1);
+ /* Enable only Rx section */
+ UCSR0B = BV(RXEN);
+ return NULL;
+}
+
+
+/**
+ * Clean up serial port, disabling the associated hardware.
+ */
+void _ser_close(void)
+{
+ /* Disable Rx & Tx. */
+ UCSR0B &= ~(BV(RXEN) | BV(TXEN));
+}