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//******************************************************************************
// MSP430F21x2 Demo - Software Toggle P1.0, MCLK = VLO/8
//
// Description; Pulse P1.0 with a 1/100 active duty cycle using software.
// Ultra-low frequency ~ 1.5kHz, ultra-low power active mode demonstrated.
// ACLK = VL0, MCLK = VLO/8 ~1.5kHz, SMCLK = n/a
//
// MSP430F21x2
// -----------------
// /|\| XIN|-
// | | |
// --|RST XOUT|-
// | |
// | P1.0|-->LED
//
// A. Dannenberg
// Texas Instruments Inc.
// October 2006
// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.41A
//******************************************************************************
#include "msp430x21x2.h"
volatile unsigned int i; // volatile to prevent optimization
void main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop watchdog timer
BCSCTL3 |= LFXT1S_2; // LFXT1 = VLO
IFG1 &= ~OFIFG; // Clear OSCFault flag
__bis_SR_register(SCG1 + SCG0); // Stop DCO
BCSCTL2 |= SELM_3 + DIVM_3; // MCLK = LFXT1/8
P1DIR = 0xFF; // All P1.x outputs
P1OUT = 0; // All P1.x reset
P2SEL = 0; // All P2.x GPIO function
P2DIR = 0xFF; // All P2.x outputs
P2OUT = 0; // All P2.x reset
P3DIR = 0xFF; // All P3.x outputs
P3OUT = 0; // All P3.x reset
for (;;)
{
P1OUT |= 0x01; // P1.0 set
for (i = 10; i > 0; i--); // Delay 1x
P1OUT &= ~0x01; // P1.0 reset
for (i = 1000; i > 0; i--); // Delay 100x
}
}
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