nes-proj/cpu/msp430/f5xxx/uart1.c
2015-11-17 20:26:43 +05:30

177 lines
5.3 KiB
C

/*
* Copyright (c) 2011, 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.
*/
/*
* Yet another machine dependent MSP430X UART0 code.
* IF2, etc. can not be used here... need to abstract to some macros
* later.
*/
#include "contiki.h"
#include <stdlib.h>
#include "sys/energest.h"
#include "dev/uart1.h"
#include "dev/watchdog.h"
#include "isr_compat.h"
static int (*uart1_input_handler)(unsigned char c);
static volatile uint8_t transmitting;
#ifdef UART1_CONF_RX_WITH_DMA
#define RX_WITH_DMA UART1_CONF_RX_WITH_DMA
#else /* UART1_CONF_RX_WITH_DMA */
#define RX_WITH_DMA 1
#endif /* UART1_CONF_RX_WITH_DMA */
#if RX_WITH_DMA
#define RXBUFSIZE 128
static uint8_t rxbuf[RXBUFSIZE];
static uint16_t last_size;
static struct ctimer rxdma_timer;
static void
handle_rxdma_timer(void *ptr)
{
uint16_t size;
size = DMA0SZ; /* Note: loop requires that size is less or eq to RXBUFSIZE */
while(last_size != size) {
uart1_input_handler((unsigned char)rxbuf[RXBUFSIZE - last_size]);
last_size--;
if(last_size == 0) {
last_size = RXBUFSIZE;
}
}
ctimer_reset(&rxdma_timer);
}
#endif /* RX_WITH_DMA */
/*---------------------------------------------------------------------------*/
uint8_t
uart1_active(void)
{
return (UCA1STAT & UCBUSY) | transmitting;
}
/*---------------------------------------------------------------------------*/
void
uart1_set_input(int (*input)(unsigned char c))
{
#if RX_WITH_DMA /* This needs to be called after ctimer process is started */
ctimer_set(&rxdma_timer, CLOCK_SECOND / 64, handle_rxdma_timer, NULL);
#endif
uart1_input_handler = input;
}
/*---------------------------------------------------------------------------*/
void
uart1_writeb(unsigned char c)
{
watchdog_periodic();
/* Loop until the transmission buffer is available. */
while((UCA1STAT & UCBUSY));
/* Transmit the data. */
UCA1TXBUF = c;
}
/*---------------------------------------------------------------------------*/
/**
* Initalize the RS232 port.
*
*/
void
uart1_init(unsigned long ubr)
{
/* RS232 */
UCA1CTL1 |= UCSWRST; /* Hold peripheral in reset state */
UCA1CTL1 |= UCSSEL_2; /* CLK = SMCLK */
ubr = (MSP430_CPU_SPEED / ubr);
UCA1BR0 = ubr & 0xff;
UCA1BR1 = (ubr >> 8) & 0xff;
/* UCA1MCTL |= UCBRS_2 + UCBRF_0; // Modulation UCBRFx=0 */
UCA1MCTL = UCBRS_3; /* Modulation UCBRSx = 3 */
P4DIR |= BIT5;
P4OUT |= BIT5;
P5SEL |= BIT6 | BIT7; /* P5.6,7 = USCI_A1 TXD/RXD */
P4SEL |= BIT7;
P4DIR |= BIT7;
/*UCA1CTL1 &= ~UCSWRST;*/ /* Initialize USCI state machine */
transmitting = 0;
/* XXX Clear pending interrupts before enable */
UCA1IE &= ~UCRXIFG;
UCA1IE &= ~UCTXIFG;
UCA1CTL1 &= ~UCSWRST; /* Initialize USCI state machine **before** enabling interrupts */
UCA1IE |= UCRXIE; /* Enable UCA1 RX interrupt */
#if RX_WITH_DMA
UCA1IE &= ~UCRXIE; /* disable USART1 RX interrupt */
/* UART1_RX trigger */
DMACTL0 = DMA0TSEL_20;
/* source address = RXBUF1 */
DMA0SA = (unsigned int)&UCA1RXBUF;
DMA0DA = (unsigned int)&rxbuf;
DMA0SZ = RXBUFSIZE;
last_size = RXBUFSIZE;
DMA0CTL = DMADT_4 + DMASBDB + DMADSTINCR_3 + DMAEN + DMAREQ;
msp430_add_lpm_req(MSP430_REQUIRE_LPM1);
#endif /* RX_WITH_DMA */
}
/*---------------------------------------------------------------------------*/
#if !RX_WITH_DMA
ISR(USCI_A1, uart1_rx_interrupt)
{
uint8_t c;
ENERGEST_ON(ENERGEST_TYPE_IRQ);
if(UCA1IV == 2) {
if(UCA1STAT & UCRXERR) {
c = UCA1RXBUF; /* Clear error flags by forcing a dummy read. */
} else {
c = UCA1RXBUF;
if(uart1_input_handler != NULL) {
if(uart1_input_handler(c)) {
LPM4_EXIT;
}
}
}
}
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
#endif /* !RX_WITH_DMA */
/*---------------------------------------------------------------------------*/