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//******************************************************************************
// MSP430F20xx 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 *//
//
// MSP430F20xx
// -----------------
// /|\| XIN|-
// | | | 32kHz
// --|RST XOUT|-
// | |
// | P1.1/TA0|--> ACLK/20
//
// M. Buccini / L. Westlund
// Texas Instruments Inc.
// October 2005
// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.40A
//******************************************************************************
#include <msp430x20x3.h>
void 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
}
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