Hello Team,
Posting on behalf of my customer:
Using CCSv12.
I set up the ADC to read a voltage on one channel, then later switch the channel using
ADC10AE0 = (ADC10AE0 & ~ADC2)|ADC1; // here ADC1 is defined as BIT4
ADC10CTL1 = (ADC10CTL1 & ~INCH_15)|INCH_4; // Selects Channel 4
The problem is the ADC10CTL1 register does not change after executing the line that is supposed to change it.
Any clues or help would be appreciated as to how to change ADC channels. I have used CONSEQ before, but I am specifically changing channels to read one channel at a time for this case. My full code is below.
#include <msp430.h>
#define STEP1 BIT1 // P2.1 TA1.1
#define STEP2 BIT4 // P2.4 TA1.2
#define DIR1 BIT2 // P2.2
#define DIR2 BIT3 // P2.3
#define ADC1 BIT4 // P1.4
#define ADC2 BIT5 // P1.5
#define HYST 10 // hysteresis for pot comparator value
#define PERIOD 1000 // timer ticks for 5 steps/s (200 ms)
#define PULSE 200 // timer ticks for minimum step time
int potPos1; //Declare variable to take ADC value
int motorPos1=0;
int delta1;
int potPos2; //Declare variable to take ADC value
int motorPos2=0;
int delta2;
void main(void)
{
WDTCTL = WDTPW | WDTHOLD; // stop watchdog timer
//Set clock speed to be sure it is 1MHz
BCSCTL1 = CALBC1_1MHZ; //Basic Clock System CTL (1,8,12,16_MHZ available)
DCOCTL = CALDCO_1MHZ; //Digitally-Controlled Oscillator CTL
// motor pins
P2DIR |= STEP1+STEP2;
P2OUT &= ~(STEP1+STEP2);
P2SEL &= ~(STEP1+STEP2); // initially off--select timer when stepping is needed
P2DIR |= DIR1+DIR2;
P2OUT |= DIR1+DIR2; // initially + direction=1
// Initialize P1.4 as the ADC input
ADC10CTL0 = ADC10SHT_2 + ADC10ON + ADC10IE; // ADC10 control register
// ADC10SHT_2: ADC10 sample-and-hold time = 16 x ADC10CLKs
// ADC10ON: ADC10 On/Enable
// ADC10IE: ADC10 Interrupt Enable (flag set when ADC10MEM ready)
ADC10CTL1 = INCH_4; // Selects Channel (initially INCH_4)
ADC10AE0 |= ADC1; // Analog Input Enable (initially ADC1=BIT4)
// set up timer for the stepper rate
TA1CTL = TASSEL_2 + MC_1 + ID_3; // SMCLK, up mode, divide by 8
TA1CCR0 = PERIOD; // timer step period
TA1CCR1 = PULSE;
TA1CCTL1 = OUTMOD_7; // PWM timer for motor 1
TA1CCTL2 = OUTMOD_7; // PWM timer for motor 2
TA1CCTL0 = CCIE;
// main while(1) infinite loop with state machine, sleep & wake, or just sleep (LPM)
while(1){
if(ADC10AE0 & ADC1){
ADC10CTL1 = (ADC10CTL1 & ~INCH_15)|INCH_5; // Selects Channel 5
}
else{
ADC10CTL1 = (ADC10CTL1 & ~INCH_15)|INCH_4; // Selects Channel 4
}
__bis_SR_register(LPM0_bits + GIE);
}
}
// ADC10 interrupt service routine
#pragma vector=ADC10_VECTOR
__interrupt void ADC10_ISR (void)
{
if(ADC10AE0 & ADC1){
potPos1 = ADC10MEM;
if((potPos1-HYST) > motorPos1){
P2OUT |= DIR1; // + direction
delta1 = potPos1 - motorPos1;
P2SEL |= STEP1;
}
else if((potPos1+HYST) < motorPos1){
P2OUT &= ~DIR1; // - direction
delta1 = motorPos1 - potPos1;
P2SEL |= STEP1;
}
else{
P2SEL &= ~STEP1;
delta1 = 0;
}
ADC10AE0 = (ADC10AE0 & ~ADC1)|ADC2; // Analog Input Enable
__no_operation();
}
else{
potPos2 = ADC10MEM;
if((potPos2-HYST) > motorPos2){
P2OUT |= DIR2; // + direction
delta1 = potPos2 - motorPos2;
P2SEL |= STEP2;
}
else if((potPos2+HYST) < motorPos2){
P2OUT &= ~DIR2; // - direction
delta2 = motorPos1 - potPos1;
P2SEL |= STEP2;
}
else{
P2SEL &= ~STEP2;
delta2 = 0;
}
ADC10AE0 = (ADC10AE0 & ~ADC2)|ADC1; // Analog Input Enable
}
__bic_SR_register_on_exit(LPM0_bits); // return on exit
}
// Timer ISR for TA1CCR0 interrupt
#pragma vector = TIMER1_A0_VECTOR
__interrupt void TA1_ISR(void) {
// Read the analog voltage at the ADC
ADC10CTL0 |= ENC + ADC10SC; // ADC10 Enable Conversion
if(P2SEL & STEP1){
if(P2OUT & DIR1) motorPos1++;
else motorPos1--;
delta1--;
if(!delta1) P2SEL &= ~STEP1;
}
if(P2SEL & STEP2){
if(P2OUT & DIR2) motorPos2++;
else motorPos2--;
delta2--;
if(!delta2) P2SEL &= ~STEP2;
}
}
Regards,
Renan
