Микропроцессорная техника / MSP430G2xx3_Code_Examples / msp430g2xx3_ta_11

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 *                       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--*/
//******************************************************************************
//  MSP430G2xx3 Demo - Timer_A, Toggle P1.1/TA0, Up Mode, 32kHz ACLK
//
//  Description: Toggle P1.1 using hardware TA0 output. Timer_A is configured
//  for up mode with CCR0 defining period, TA0 also output on P1.1. In this
//  example, CCR0 is loaded with 10-1 and TA0 will toggle P1.1 at TACLK/10.
//  Thus the output frequency on P1.1 will be the TACLK/20. No CPU or software
//  resources required. Normal operating mode is LPM3.
//  ACLK= TACLK = 32kHz, MCLK = default DCO
//  As coded with TACLK = ACLK, P1.1 output frequency = 32768/20 = 1.6384kHz
//  //* External watch crystal installed on XIN XOUT is required for ACLK *//
//
//            MSP430G2xx3
//         -----------------
//     /|\|              XIN|-
//      | |                 | 32kHz
//      --|RST          XOUT|-
//        |                 |
//        |         P1.1/TA0|--> ACLK/20
//
//  D. Dang
//  Texas Instruments Inc.
//  December 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
  P1DIR |= 0x02;                            // P1.1 output
  P1SEL |= 0x02;                            // P1.1 option select
  CCTL0 = OUTMOD_4;                         // CCR0 toggle mode
  CCR0 = 10-1;
  TACTL = TASSEL_1 + MC_1;                  // ACLK, upmode

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