test44x_ta05.c

来自「msp430系列开发板源代码」· C语言 代码 · 共 58 行

//******************************************************************************
//  MSP430-TEST44X Demo - Timer_A Toggle P5.1, CCR0 upmode ISR, 32kHz ACLK
//
//  Description; Toggle P5.1 using software and the TA_0 ISR. Timer_A is
//  configured in an upmode, thus the the timer will overflow when TAR counts
//  to CCR0. In this example, CCR0 is loaded with 1000.
//  Toggle rate = 32768/(2*1000) = 16.384
//  ACLK = TACLK = LFXT1 = 32768, MCLK = SMCLK = DCO = 32xACLK = 1.048576MHz
//  //*An external watch crystal on XIN XOUT is required for ACLK*//	
//
//           MSP430F449
//         ---------------
//     /|\|            XIN|-
//      | |               | 32kHz
//      --|RST        XOUT|-
//        |               |
//        |           P5.1|-->LED
//  zhangchong
//  Lierda, Inc
//  February 2006.03
//  Built with IAR Embedded Workbench Version: 3.40a
//  ID：  MSP430-TEST44X
//  DATA：2005-7-12
//  REV： 2.0A
//  程序功能：该程序是用F449的内部TIMER_A CCR0的比较模式功能，来控制P5.1口驱动LED 1S(32768/32.768)闪烁。
//  硬件连接：先连接P5.1口的短接器，然后连接键盘上方的短接器J2。
//
//******************************************************************************

#include <msp430x44x.h>

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;             // Stop WDT
  FLL_CTL0 |= XCAP14PF;                 // Configure load caps
  TACTL = TASSEL0 + TACLR;              // ACLK, clear TAR
  CCTL0 = CCIE;                         // CCR0 interrupt enabled
  CCR0 = 32768;
  P5DIR |= 0x02;                        // Set P5.1 to output direction
  TACTL |= MC0;                         // Start Timer_a in upmode
  _EINT();                              // Enable interrupts

  for (;;)
  {
    _BIS_SR(LPM3_bits);                 // Enter LPM3
    _NOP();                             // Required only for C-spy
  }
}

// Timer A0 interrupt service routine
//interrupt[TIMERA0_VECTOR] void Timer_A (void)
#pragma vector=TIMERA0_VECTOR
__interrupt void Timer_A (void)
{
    P5OUT ^= 0x02;                      // Toggle P5.1 using exclusive-OR
}