Hi
I am trying to use the comparator B and timer A0 interrupts on the msp430f5529 .The code is written in Energia and imported into CCS:
#include <msp430.h>
int count =0;
int x=5;
int time1=0;
int time2=0;
void setup()
{ volatile unsigned int i;
Serial.begin(9600);
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
P1DIR |= BIT0; // P1.0/LED output direction
P4DIR |=BIT7;
// Setup ComparatorB
CBCTL0 |= CBIPEN + CBIPSEL_0; // Enable V+, input channel CB0
CBCTL1 |= CBPWRMD_0; // ULTRA LOW power mode
CBCTL2 |= CBRSEL; // VREF is applied to -terminal
CBCTL2 |= CBRS_3|CBREFL_3; // R-ladder off; bandgap ref voltage (1.2V)
// supplied ref amplifier to get Vcref=2.5V (CBREFL_3)
CBCTL3 = BIT0; // Input Buffer Disable @P6.0/CB0
__delay_cycles(75); // delay for the reference to settle
CBINT &= ~(CBIFG | CBIIFG); // Clear any errant interrupts
CBINT |= CBIE; // Enable CompB Interrupt on rising edge of CBIFG (CBIES=0)
CBCTL1 |= CBON + CBIES; // Turn On ComparatorB
TA0CTL = TASSEL_1| MC_2 | TACLR |TAIE;//Enable Timer interrupt in Continuous mode
enableWatchDog();
__bis_SR_register(LPM3_bits|GIE); // Enter LPM3 with inetrrupts enabled
}
// Comp_B ISR - LED Toggle
#pragma vector=COMP_B_VECTOR
__interrupt void Comp_B_ISR (void)
{
CBCTL1 ^= CBIES; // Toggles interrupt edge
CBINT &= ~(CBIFG | CBIIFG); // Clear Interrupt flag
P1OUT ^= 0x01; // Toggle P1.0
}
//Timer A1 ISR
#pragma vector=TIMER0_A1_VECTOR
__interrupt void TIMER0_A1_ISR(void)
{
if( CBOUT ==1)
{ count =1;
P4OUT ^=BIT7;
delay(1000);
}
else{P4OUT ^=BIT7;
delay(1000);
count =0;}
}
void loop()
{enableWatchDog();
Serial.println("HELLO");
Serial.println(count);
sleepcount(x);
delay(1000);
__bis_SR_register(GIE);
}
int sleepcount(int y)
{enableWatchDog();
time1=millis();
if (count == 1)
{sleepSeconds(x);
x=x+1;}
else
{delay(x*1000);
x=x-1;
if(x==0){x=10;}
else{}}
time2=millis();
Serial.println(time2-time1);
}
I get the following output:
When voltage applied is less than or more 2.5 V Green and Red led toggle alternatively.(GREEN ON RED OFF and vice versa) .
According to the code I am following once the processor enters the comparator interrupt for V>2.5 V it should toggle RED LED and stay in that state until V<2.5 V
The problem seems to be that the Comparator interrupt somehow resets all of its flags .
Also the Serial print statement gives value 0 for (time2-time1) and if I do not enable the Watch Dog before entering into LPM3 it does not even print "HELLO".
