Hello,
I am using my own board for MSP432P401M. The ADC has external reference voltages is 3.3V and I can successfully sample the voltage. A single sample is made on A1 with reference to AVcc.ADC14 internal oscillator times sample (16x) and conversion. Timer 32 (module 0) is set up in 32-bit, free-run, and periodic mode.Timer count is loaded with an initial value of 0xFFFFFF. The timer interrupt triggers and the ISR is executed. Within the ISR, Software sets ADC14_CTL0_SC to start sample and conversion - ADC14_CTL0 automatically cleared at EOC and increment the value of counter n.It just clears the interrupt flag and exits back to the main application and enters a while loop.
1) when this code is debug, value of counter m and n is increment but response is very slow.
This is my code:-
#include "MSP432P401M.h"
#include <stdint.h>
unsigned int i;
unsigned int j;
unsigned int l=1;
//Counters for debugging
unsigned int m=0;
unsigned int n=0;
//*************************************************************************************
//Main code
int main(void)
{
//Stop watchdog timer
WDT_A->CTL = WDT_A_CTL_PW | WDT_A_CTL_HOLD;
// GPIO setting
P5->SEL1 |= BIT4; // Configure P5.4 for ADC
P5->SEL0 |= BIT4;
// UNUSED pin setup
P10->DIR &= ~(BIT0 + BIT1 + BIT2 + BIT3); // set P10 as input direction
P10->REN |= BIT0 + BIT1 + BIT2 + BIT3; //enable pull-up/pull-down resistors on P10
P10->OUT &= ~(BIT0 + BIT1 + BIT2 + BIT3); //Set P10 resistors to pull down
P1->DIR &= ~(BIT1 + BIT4 + BIT5 + BIT6 + BIT7);
P1->REN |= BIT1 + BIT4 + BIT5 + BIT6 + BIT7;
P1->OUT &= ~(BIT1 + BIT4 + BIT5 + BIT6 + BIT7);
P2->DIR &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P2->REN |= BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7;
P2->OUT &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P8->DIR &= BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7;
P8->REN |= BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7;
P8->OUT &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P9->DIR &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5);
P9->REN |= BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 ;
P9->OUT &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5);
P6->DIR &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P6->REN |= BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7;
P6->OUT &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P4->DIR &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P4->REN |= BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7;
P4->OUT &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P5->DIR &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P5->REN |= BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7;
P5->OUT &= ~(BIT0 + BIT1 + BIT2 + BIT3 + BIT4 + BIT5 + BIT6 + BIT7);
P7->DIR &= ~(BIT0 + BIT1 + BIT2 + BIT3);
P7->REN |= BIT0 + BIT1 + BIT2 + BIT3;
P7->OUT &= ~(BIT0 + BIT1 + BIT2 + BIT3);
//ADC Setup
ADC14->CTL0 = ADC14_CTL0_SHT0_2 | ADC14_CTL0_SHP | ADC14_CTL0_ON; // Sampling time, S&H=16, ADC14 on
//ADC14->CTL1 = ADC14_CTL1_RES_2; // Use sampling timer, 12-bit conversion results
ADC14->CTL1 = ADC14_CTL1_RES_3; // Use sampling timer, 14-bit conversion results
ADC14->MCTL[0] |= ADC14_MCTLN_INCH_1; // A1 ADC input select; Vref=AVCC
// ADC14->IER0 |= ADC14_IER0_IE0; // Enable ADC conv complete interrupt
while (1)
{
if(l == 1)
{
// Timer32 set up in periodic ,free run, 32-bit, no pre-scale
TIMER32_1->CONTROL = TIMER32_CONTROL_SIZE | TIMER32_CONTROL_ONESHOT;
// Load Timer32 Counter with initial value
TIMER32_1->LOAD= 0xFFFFFF;
// Enable the Timer32 interrupt in NVIC
__enable_irq();
NVIC->ISER[0] = 1 << ((T32_INT1_IRQn) & 31);
// Disable sleep on exit from ISR
SCB->SCR &= ~SCB_SCR_SLEEPONEXIT_Msk;
// Start Timer32 and enable interrupt
TIMER32_1->CONTROL |= TIMER32_CONTROL_ENABLE | TIMER32_CONTROL_IE;
// Enter LPM0 and wait for the timer interrupt to wake-up
// __sleep();
// __no_operation();
m++;
if (m>50000)
{
m=0;
}
l=0;
}
}
}
void T32_INT1_IRQHandler(void)
{
// P1->OUT ^= BIT0; // Toggle P1.0 LED
// Start sampling/conversion
ADC14->CTL0 |= ADC14_CTL0_ENC | ADC14_CTL0_SC;
n++;
if (n==50000)
{
n=0;
}
TIMER32_1->INTCLR |= BIT0; // Clear Timer32 interrupt flag
// Disable the timer and interrupt
TIMER32_1->CONTROL &= ~(TIMER32_CONTROL_ENABLE |TIMER32_CONTROL_IE);
l= 1;
}
2) if l am removing l=1 from my code then counter n is not increment
This is my code:-
(GPIO pin setup and ADC setup is same as above code)
while (1)
{
// Timer32 set up in periodic ,free run, 32-bit, no pre-scale
TIMER32_1->CONTROL = TIMER32_CONTROL_SIZE | TIMER32_CONTROL_ONESHOT;
// Load Timer32 Counter with initial value
TIMER32_1->LOAD= 0xFFFFFF;
// Enable the Timer32 interrupt in NVIC
__enable_irq();
NVIC->ISER[0] = 1 << ((T32_INT1_IRQn) & 31);
// Disable sleep on exit from ISR
SCB->SCR &= ~SCB_SCR_SLEEPONEXIT_Msk;
// Start Timer32 and enable interrupt
TIMER32_1->CONTROL |= TIMER32_CONTROL_ENABLE | TIMER32_CONTROL_IE;
// Enter LPM0 and wait for the timer interrupt to wake-up
// __sleep();
// __no_operation();
m++;
if (m>50000)
{
m=0;
}
}
void T32_INT1_IRQHandler(void)
{
// P1->OUT ^= BIT0; // Toggle P1.0 LED
// Start sampling/conversion
ADC14->CTL0 |= ADC14_CTL0_ENC | ADC14_CTL0_SC;
n++;
if (n==50000)
{
n=0;
}
TIMER32_1->INTCLR |= BIT0; // Clear Timer32 interrupt flag
// Disable the timer and interrupt
TIMER32_1->CONTROL &= ~(TIMER32_CONTROL_ENABLE |TIMER32_CONTROL_IE);
}
Why the counter value n is not incremented??
