nes-proj/cpu/msp430/dev/uart1.c

137 lines
4.2 KiB
C

/*
* Copyright (c) 2006, Swedish Institute of Computer Science
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)$Id: uart1.c,v 1.3 2007/09/06 11:45:08 nvt-se Exp $
*/
/*
* Machine dependent MSP430 UART1 code.
*/
#include <stdlib.h>
#include <io.h>
#include <signal.h>
#include "lib/energest.h"
#include "dev/uart1.h"
static void (*uart1_input_handler)(unsigned char c);
/*---------------------------------------------------------------------------*/
void
uart1_set_input(void (*input)(unsigned char c))
{
uart1_input_handler = input;
}
/*---------------------------------------------------------------------------*/
void
uart1_writeb(unsigned char c)
{
/* Loop until the transmission buffer is available. */
while ((IFG2 & UTXIFG1) == 0);
/* Transmit the data. */
TXBUF1 = c;
}
/*---------------------------------------------------------------------------*/
int
putchar(int c)
{
uart1_writeb((char)c);
return c;
}
/*---------------------------------------------------------------------------*/
/**
* Initalize the RS232 port.
*
*/
void
uart1_init(unsigned long ubr)
{
/* RS232 */
P3DIR &= ~0x80; /* Select P37 for input (UART1RX) */
P3DIR |= 0x40; /* Select P36 for output (UART1TX) */
P3SEL |= 0xC0; /* Select P36,P37 for UART1{TX,RX} */
UCTL1 = SWRST | CHAR; /* 8-bit character, UART mode */
#if 0
U1RCTL &= ~URXEIE; /* even erroneous characters trigger interrupts */
#endif
UTCTL1 = SSEL1; /* UCLK = MCLK */
UBR01 = ubr;
UBR11 = ubr >> 8; /* always zero */
/*
* UMCTL1 values calculated using
* http://mspgcc.sourceforge.net/baudrate.html and are not
* complete. Also the table assumes that F_CPU = 2,457,600 Hz.
*/
switch(ubr) {
case UART1_BAUD2UBR(115200):
UMCTL1 = 0x4a;
break;
case UART1_BAUD2UBR(57600):
UMCTL1 = 0x5b;
break;
case UART1_BAUD2UBR(19600):
UMCTL1 = 0x4a;
break;
default:
UMCTL1 = 0x00;
}
ME2 &= ~USPIE1; /* USART1 SPI module disable */
ME2 |= (UTXE1 | URXE1); /* Enable USART1 TXD/RXD */
UCTL1 &= ~SWRST;
/* XXX Clear pending interrupts before enable!!! */
IE2 |= URXIE1; /* Enable USART1 RX interrupt */
}
/*---------------------------------------------------------------------------*/
interrupt(UART1RX_VECTOR)
uart1_interrupt(void)
{
ENERGEST_ON(ENERGEST_TYPE_IRQ);
/* Check status register for receive errors. */
if(URCTL1 & RXERR) {
volatile unsigned dummy;
dummy = RXBUF1; /* Clear error flags by forcing a dummy read. */
} else {
if (uart1_input_handler != NULL) {
uart1_input_handler(RXBUF1);
LPM4_EXIT;
}
}
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/