uart.c

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/*
 * File:        uart.c
 * Purpose:     Serial interface functions
 * Author:      Peter Ivanov
 * Modified by:
 * Created:     2007-05-19 11:31:29
 * Last modify: 2007-12-27 14:12:46 ivanovp {Time-stamp}
 * Copyright:   (C) Peter Ivanov, 2007
 * Licence:     GPL
 */
/**
 * \file uart.c
 * \brief Serial interface functions
 * \author Peter Ivanov
 */
#include <msp430x44x.h>
#include <msp430/basic_clock.h>
#include <msp430/system_clock.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include "uart.h"

/**
 * Initialize UART (RS232) port: 9600 baud, 8n1.
 */
void UART_init (void)
{
    //UART ini
    U1TCTL = SSEL0;                     // UCLOCK = ACLK
    U1BR0 = 0x03;                       // BAUD RATE = 9600
    U1BR1 = 0x00;
    U1MCTL = 0x4a;                      // with modulation
    U1CTL = CHAR;                       // Start 8bit 1stop, N
    ME2 = UTXE1 | URXE1;                // enable RX and TX
    P4SEL |= BIT0 | BIT1;               // select UART pins
    P4DIR |= BIT0;                      // port direction for TXD0
    P4DIR &= ~BIT1;                     // port direction for RXD0
    //IE1 |= URXIE0;                    // Enable USART0 RX interrupt
    //_EINT();                          // Enable interrupts
    //U1CTL &= ~SWRST;                  //reset UART logic
}

/**
 * Send ony byte via UART.
 *
 * @param c Character to send.
 */
void UART_putChar (char c)              // UART1 Transmit Subroutine
{
    while ((IFG2 & UTXIFG1) == 0);      // Wait for ready U1TXBUF
    U1TXBUF = c;                        // send data
}

/**
 * Check UART's input buffer.
 *
 * @return TRUE: if input buffer contains received data.
 */
char UART_getCharIsReady ()
{
    return (IFG2 & URXIFG1) != 0;
}

/**
 * Receive one byte via UART. This function waits for the input (blocking).
 *
 * @return Received character.
 */
char UART_getChar ()
{
    while (!UART_getCharIsReady ());
    return U1RXBUF;
}

/**
 * Write string buffer to UART.
 *
 * @param buf String buffer to send.
 * @param length Length of string buffer.
 */
void UART_write (const char *buf, int length)
{
    int i;
    for (i = 0; i < length; i++)
    {
        UART_putChar (buf[i]);
    }
}

/**
 * Printf function which uses UART interface to send.
 * Example:
<pre>
UART_printf ("Number: %02i\r\n", number);
</pre>
 *
 * @param fmt Printf format string. Example: "Value: %02i\r\n"
 */
void UART_printf (const char *fmt, ...)
{
    static va_list valist;
    char buf[UART_PRINTF_BUF_SIZE];
    
    va_start (valist, fmt);
    vsnprintf (buf, sizeof (buf), fmt, valist);
    va_end (valist);    
    UART_write (buf, strlen (buf));
}

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