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#include <msp430.h>
/* * main.c */ volatile unsigned long doublemillis = 0; volatile int j = 0; volatile int brainFq[] = {
15, //1 14, //2 13, //3 12, //4 11, //5 10, //6 9, //7 8, //8 7, //9 6, //10 5, //11 4, //12 7, //13 6, //14 5, //15 4, //16 6, //17 5, //18 4, //19 5, //20 6, //21 7, //22 8, //23 9, //24 10, //25 11, //26 12, //27 13, //28 14, //29 15, //30
}; volatile int brainDuration[] = {
20, //1 20, //2 20, //3 20, //4 20, //5 20, //6 20, //7 30, //8 30, //9 30, //10 30, //11 40, //12 5, //13 10, //14 20, //15 60, //16 5, //17 10, //18 30, //19 5, //20 5, //21 5, //22 5, //23 5, //24 5, //25 5, //26 5, //27 5, //28 5, //29 25, //30
}; volatile int ArrayLength = 30; volatile int on = 0; Declaration of functions int FreqTime(int Hz); int FreqCycle(int Hz , unsigned long speed); unsigned long millis(); int blinkms(int Millis); int CountByTime(int duration, int ArrayLength); MAIN program int main(void) {
// Set Watchdog as timer with an interrupt every 0.5ms BCSCTL1 = CALBC1_1MHZ; DCOCTL = CALDCO_1MHZ; WDTCTL = WDT_MDLY_0_5; // (WDTPW+WDTTMSEL+WDTCNTCL+WDTIS1) /* 0.5ms IFG1 &= ~WDTIFG; IE1 |= WDTIE; // Enable WDT interrupt P1DIR |= 0x0F; // Set P1.0 - P1.3 as Output
P1OUT &= 0xF0; Set P1.0 - P1.3 to 0 Timer_A
TA0CCR0 = 1250; // Count limit for 400Hz at !MHz (1000000 / 400 / 2) TA0CCTL0 = 0x10; // Enable Timer A0 interrupts, bit 4=1 TA0CTL = TASSEL_2 + MC_1; // Timer A0 with SMCLK, count UP TA1CCR0 = 1250; // Count limit for 400Hz predefinitoin, will be overwriten later TA1CCTL0 = 0x10; // Enable Timer A0 interrupts, bit 4=1 TA1CTL = TASSEL_2 + MC_1; // Timer A1 with SMCLK, count UP _EINT(); //enable interrupts
Endless loop while(1){ j = CountByTime(brainDuration[j], ArrayLength); on = blinkms(FreqTime(brainFq[j])); TA1CCR0 = FreqCycle(brainFq[j]+400, 1000000); if (on){ P1OUT |= 0x03; } else{ P1OUT &= 0xFC; } } return 0; } Functions
blink in the rhythm of given ms int blinkms(int Millis){ static unsigned long PreviousMillis = 0; static int back = 0; unsigned long CurrentMillis = millis(); if (CurrentMillis - PreviousMillis >= Millis){ PreviousMillis = CurrentMillis; back ^= 0x01; } return back; } count 1 up, if time in ms done int CountByTime(int duration, int ArrayLength){
static unsigned long PreviousMillis = 0;
static int back = 0;
unsigned long Millis = duration * 1000;
unsigned long CurrentMillis = millis();
if (CurrentMillis - PreviousMillis >= Millis){
PreviousMillis = CurrentMillis;
if (back < ArrayLength) back++;
}
return back;
}
Convert frequency to ms int FreqTime(int Hz){ int v = 1000 / Hz / 2; return v; } Convert frequency to Cycles by given Clockspeed int FreqCycle(int Hz, unsigned long speed){
int v = speed / Hz / 2; return v;
}
Function that is reuturning ms since startup unsigned long millis(){ return doublemillis » 1; Double Millisecondy divided by 2 }
————————– Interrupts —————————————— #pragma vector=WDT_VECTOR interrupt void WDT(void){ doublemillis++; } #pragma vector=TIMER0_A0_VECTOR Timer0 A0 interrupt service routine interrupt void Timer0_A0 (void) { P1OUT ^= 0x04; Toggle output P1.2 } #pragma vector=TIMER0_A1_VECTOR Timer1 A0 interrupt service routine interrupt void Timer1_A0 (void) { P1OUT ^= 0x08; Toggle output P1.3 }