I am trying to do the following:
On each trigger from timer B CCR1, sample 9 channels and stop, with a single interrupt on the last conversion, to collect the data.
I would like this to run automatically, without having to manually toggle any bits. Is this possible?
I initialize stuff like this:
//timer B: 400Hz & A/D trigger
P3DIR |= BIT6; // P3.6 output PIN 43 400Hz
P3SEL |= BIT6; // P3.6 option select (TB0.6)
//ccr0 sets period
TBCCR0 = 29999; // 400Hz @24MHz (half period, toggle)
//ccr1 triggers A/D
TBCCR1 = 5; // just a narrow pulse for trigger
TBCCTL1 = OUTMOD_7; // CCR1 reset/set mode A/D trig
P5DIR |= BIT7; P5SEL |= BIT7; // (DEBUG) output pin 56 (disp pin 6)
//ccr6 generates 400Hz output
TBCCTL6 = OUTMOD_4; // toggle, pin 43 for 400Hz output
TBCCR6 = 3000; // phase offset (to sample at sinewave peaks)
TBCTL = TBSSEL_2 + MC_1; // SMCLK, upmode
//ADC12 (tudi za potenciometre)
ADC12CTL0 = ADC12ON; // ADC12 on
ADC12CTL0 &= ~ADC12ENC;
while (ADC12CTL1 & ADC12BUSY);
P6SEL |= BIT4+BIT5+BIT6+BIT7; // P6 ADC option select
P7SEL |= BIT0+BIT1+BIT2+BIT3; // P7 ADC option select
P5SEL |= BIT0+BIT1; // P7 ADC option select (potenc)
ADC12CTL0 |= ADC12SHT00 + ADC12SHT10; // Sampling time, chans 0...7 & 8...15
ADC12CTL0 |= ADC12MSC;
ADC12MCTL0 = ADC12INCH_4; // ref=Vcc,Vss, chan 4
ADC12MCTL1 = ADC12INCH_5; // ref=Vcc,Vss, chan 5
ADC12MCTL2 = ADC12INCH_6; // ref=Vcc,Vss, chan 6
ADC12MCTL3 = ADC12INCH_7; // ref=Vcc,Vss, chan 7
ADC12MCTL4 = ADC12INCH_12; // ref=Vcc,Vss, chan 12
ADC12MCTL5 = ADC12INCH_13; // ref=Vcc,Vss, chan 13
ADC12MCTL6 = ADC12INCH_14; // ref=Vcc,Vss, chan 14
ADC12MCTL7 = ADC12INCH_15; // ref=Vcc,Vss, chan 15
ADC12MCTL8 = ADC12INCH_8; // ref=Vcc,Vss, chan 8 (potenc)
ADC12MCTL9 = ADC12INCH_9 + ADC12EOS; // ref=Vcc,Vss, chan 9 (potenc), end of seq
ADC12CTL1 = ADC12SHS_3; // trig = timer B CCR1
ADC12CTL1 |= ADC12SHP; // pulse mode sampling
ADC12CTL1 |= ADC12CSTARTADD_0; // start address
ADC12CTL1 |= ADC12CONSEQ_3; // repeat sequence of chans
//ADC12CTL1 |= ADC12CONSEQ_1; // sequence of chans (toggle ADC12ENC!)
ADC12CTL2 |= ADC12RES_2; // 12 bit resolution
ADC12IE = ADC12IE9; // enable interrupt on last conversion
ADC12CTL0 |= ADC12ENC; // enable conversion (must be last)
for now, the interrupt just toggles a pin, so I can see it happen:
#pragma vector = ADC12_VECTOR
__interrupt void ADC12_ISR(void)
{
switch (ADC12IV)
{
case 0: break; // Vector 0: No interrupt
case 2: break; // Vector 2: ADC overflow
case 4: break; // Vector 4: ADC timing overflow
case 6: break; // Vector 6: ADC12IFG0
case 8: break; // Vector 8: ADC12IFG1
case 10: break; // Vector 10: ADC12IFG2
case 12: break; // Vector 12: ADC12IFG3
case 14: break; // Vector 14: ADC12IFG4
case 16: break; // Vector 16: ADC12IFG5
case 18: break; // Vector 18: ADC12IFG6
case 20: break; // Vector 20: ADC12IFG7
case 22: break; // Vector 22: ADC12IFG8
case 24: break; // Vector 24: ADC12IFG9
case 26: break; // Vector 26: ADC12IFG10
case 28: break; // Vector 28: ADC12IFG11
case 30: break; // Vector 30: ADC12IFG12
case 32: break; // Vector 32: ADC12IFG13
case 34: break; // Vector 34: ADC12IFG14
case 36: break; // Vector 36: ADC12IFG15
default: break;
}
int a=ADC12MEM9;
P1OUT ^= 0x01; // Toggle P1.0 (DEBUG)
}
The problem is, that if I set the MSC bit, the ADC keeps sampling continuously, ignoring the EOS bit, not waiting for a trigger.
If I don't set the MSC bit, ADC converts only one input for each trigger from the timer, so that the ADC interrupt hapens only after nine triggers.
