Добавил:
Upload Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
Скачиваний:
6
Добавлен:
05.03.2016
Размер:
4.99 Кб
Скачать
/* --COPYRIGHT--,BSD_EX
 * Copyright (c) 2012, Texas Instruments Incorporated
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * *  Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * *  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.
 *
 * *  Neither the name of Texas Instruments Incorporated 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
 *
 *******************************************************************************
 * 
 *                       MSP430 CODE EXAMPLE DISCLAIMER
 *
 * MSP430 code examples are self-contained low-level programs that typically
 * demonstrate a single peripheral function or device feature in a highly
 * concise manner. For this the code may rely on the device's power-on default
 * register values and settings such as the clock configuration and care must
 * be taken when combining code from several examples to avoid potential side
 * effects. Also see www.ti.com/grace for a GUI- and www.ti.com/msp430ware
 * for an API functional library-approach to peripheral configuration.
 *
 * --/COPYRIGHT--*/
//******************************************************************************
//  MSP430G2xx1 Demo - Timer_A, Toggle P1.0-2, Cont. Mode ISR, 32kHz ACLK
//
//  Description: Use Timer_A CCRx units and overflow to generate four
//  independent timing intervals. For demonstration, CCR0 and CCR1 output
//  units are optionally selected with port pins P1.1 and P1.2 in toggle
//  mode. As such, these pins will toggle when respective CCRx registers match
//  the TAR counter. Interrupts are also enabled with all CCRx units,
//  software loads offset to next interval only - as long as the interval offset
//  is aded to CCRx, toggle rate is generated in hardware. Timer_A overflow ISR
//  is used to toggle P1.0 with software. Proper use of TAIV interrupt vector
//  generator is demonstrated.
//  ACLK = TACLK = 32kHz, MCLK = SMCLK = Default DCO
//  As coded and with TACLK = 32768Hz, toggle rates are:
//  P1.1 = CCR0 = 32768/(2*4) = 4096Hz
//  P1.2 = CCR1 = 32768/(2*16) = 1024Hz
//  P1.0 = overflow = 32768/(2*65536) = 0.25Hz
//  //* External watch crystal on XIN XOUT is required for ACLK *//	
//
//              MSP430G2xx1
//            ---------------
//        /|\|            XIN|-
//         | |               | 32kHz
//         --|RST        XOUT|-
//           |               |
//           |       P1.1/TA0|--> CCR0
//           |       P1.2/TA1|--> CCR1
//           |           P1.0|--> Overflow/software
//
//  D. Dang
//  Texas Instruments Inc.
//  October 2010
//  Built with CCS Version 4.2.0 and IAR Embedded Workbench Version: 5.10
//******************************************************************************

#include <msp430.h>

int main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
  P1SEL |= 0x06;                            // P1.1 - P1.2 option select
  P1DIR |= 0x07;                            // P1.0 - P1.2 outputs
  CCTL0 = OUTMOD_4 + CCIE;                  // CCR0 toggle, interrupt enabled
  CCTL1 = OUTMOD_4 + CCIE;                  // CCR1 toggle, interrupt enabled
  TACTL = TASSEL_1 + MC_2 + TAIE;           // ACLK, contmode, interrupt enabled

  _BIS_SR(LPM3_bits + GIE);                 // Enter LPM3 w/interrupt
}

// Timer A0 interrupt service routine
#pragma vector=TIMERA0_VECTOR
__interrupt void Timer_A0 (void)
{
  CCR0 += 4;                                // Add Offset to CCR0
}

// Timer_A2 Interrupt Vector (TAIV) handler
#pragma vector=TIMERA1_VECTOR
__interrupt void Timer_A1(void)
{
  switch( TAIV )
  {
  case  2: CCR1 += 16;                      // Add Offset to CCR1
           break;
  case 10: P1OUT ^= 0x01;                   // Timer_A3 overflow
           break;
 }
}

Соседние файлы в папке MSP430G2xx1_Code_Examples