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//******************************************************************************
// MSP430F20xx Demo - Timer_A, Toggle P1.1/TA0, Up/Down Mode, DCO SMCLK
//
// Description: Toggle P1.1 using hardware TA0 output. Timer_A is configured
// for up/down mode with CCR0 defining period, TA0 also output on P1.1. In
// this example, CCR0 is loaded with 250 and TA0 will toggle P1.1 at
// TACLK/2*250. Thus the output frequency on P1.1 will be the TACLK/1000.
// No CPU or software resources required.
// ACLK = n/a, SMCLK = MCLK = TACLK = default DCO
// As coded with TACLK = SMCLK, P1.1 output frequency is ~1000000/1000
//
// MSP430F20xx
// -----------------
// /|\| XIN|-
// | | |
// --|RST XOUT|-
// | |
// | P1.1/TA0|--> SMCLK/1000
//
// 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 = 250;
TACTL = TASSEL_2 + MC_3; // SMCLK, up-downmode
_BIS_SR(CPUOFF); // CPU off
}
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