59 lines
1.9 KiB
C
59 lines
1.9 KiB
C
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#include <msp430.h>
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/**
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* main.c
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*/
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int freq[4] = {0, 128, 256, 512}; // off, 1KHz, 2 KHz, 4 Khz
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int main(void)
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{
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WDTCTL = WDT_ADLY_1000; // 1 s interval
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_EINT(); // Enable interrupts
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IE1 |= WDTIE; // Enable WDT interrupt
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P2SEL |= BIT2; // P2.2 special function (TB0 output)
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P2SEL &= ~BIT1; // Clear P2.1
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P2OUT &= ~(BIT1+BIT2); // Turn Off LED1
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TB0CTL = TBSSEL_1 + MC_1; // Upmode
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P3SEL |= 0x20; // P3.5 as special function
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P3DIR |= 0x20; // P3.5 as digital output
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TB0CCTL4 = OUTMOD_4; // TB4 output is in toggle mode
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TB0CCTL0 = freq[0];
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_BIS_SR(LPM3_bits + GIE); // Enter Low Power Mode 3
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}
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// Watchdog Timer interrupt service routine
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#pragma vector=WDT_VECTOR
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__interrupt void watchdog_timer(void)
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{
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static int i =0;
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i++;
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if(i == 1){
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TB0CCTL0= freq[0]; // f = 4 MHz
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P2OUT &=~ BIT1; // Turn on LED2
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P2OUT &= ~BIT2; // Turn Off LED1
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}
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else if(i == 2){
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TB0CCTL0= freq[2]; // f = 2 MHz
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P2OUT &= BIT1; // Turn on LED2
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P2OUT |= BIT2; // Turn Off LED1
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}
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else if(i == 3){
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TB0CCTL0= freq[3]; // f = 4 MHz
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P2OUT |= BIT1; // Turn on LED2
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P2OUT |= BIT2; // Turn Off LED1
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}
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else if(i == 4){
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TB0CCTL0= freq[1]; // f = 4 MHz
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P2OUT &=~ BIT1; // Turn on LED2
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P2OUT &= ~BIT2; // Turn Off LED1
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}
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else if(i == 5){
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TB0CCTL0= freq[3]; // f = 4 MHz
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P2OUT &=~ BIT1; // Turn on LED2
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P2OUT |= BIT2; // Turn Off LED1
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}
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}
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