ADC Trigger using PWM

Hello Vijay

SysCtlClockSet(SYSCTL_SYSDIV_2 | SYSCTL_USE_PLL| SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ);

is not correct. The System Clock Divider must be 2.5 at least for 80MHz system clock.

Secondly you have an Interrupt enable for PWM but no interrupt handler for the PWM. It may cause the PWM to go to a while(1) loop of the default interrupt handler. Can you check what your current code is executing?

the system is currently executing void PWM0IntHandler(void); function for PWM interrupt

Hello Vijay

So it is stuck in the PWM interrupt handler. Due to the load time of 100 (system clock) the PWM is taking almost all of CPU bandwidth. As an experiment, can you disable the PWM interrupt and see if the ADC interrupt handler is getting processed?

I have disabled PWM and checked it is not getting processed ???

Just one doubt is there any possibility of running 4 PWM in parallel so that i can generate a specific RGB on and OFF sequence and reduce the load on this PWM Block , is there any sample code which tells us how to run multiple PWM blocks in Parallel

Hi VR,

Seems you may not have the correct (trigger) set for the sequencer to start samples from PWM0 load. Have a look at the other directives and be sure to set the sequencer interrupt vector.

Hello Vijay

Yes, all PWM generators are independent of each other but can be forced to work together using SYNC.

When you mentioned that you have disabled PWM, what is not getting processed?

Hi Amith Ashara

I have disbled the PWM Interrupt and in debug mode i placed an brak point in the ADC Interrupt but still it is not working , i have decided to run 5 different PWM for CLOCK PULSE , R ,G,B on sequence and For ADC trigger , i will get back to you as soon as i test the PWM Module

Hi Amith Ashara

here is the reworked code i have initilised 2 PWM GEN in PWM 1 module i havce created one 50% duty cycle and the other at 90% duty cycle i have sucessfully got the PWM outputs ant the ports here is the revised code

#include <stdbool.h>
#include <stdint.h>
#include "inc/hw_ints.h"
#include "inc/hw_memmap.h"
#include "driverlib/gpio.h"
#include "driverlib/interrupt.h"
#include "driverlib/pin_map.h"
#include "driverlib/pwm.h"
#include "driverlib/sysctl.h"
#include "driverlib/uart.h"
#include "utils/uartstdio.h"
#include "driverlib/adc.h"

int Count,PWM_FREQUENCY,ui8Adjust,ui32Load, ui32PWMClock;
uint32_t ui32ADC0Value[4];
//*****************************************************************************
//
// The interrupt handler for the for PWM0 interrupts.
//
//*****************************************************************************
void
PWM0IntHandler(void)
{

}

//void ADCIntHandler(void)
//{
//
// ADCIntClear(ADC0_BASE, 0);
// ADCSequenceDataGet(ADC0_BASE, 0, ui32ADC0Value);
//}

//*****************************************************************************
//
// Configure PWM0 for a load interrupt. This interrupt will trigger everytime
// the PWM0 counter gets reloaded. In the interrupt, 0.1% will be added to
// the current duty cycle. This will continue until a duty cycle of 75% is
// received, then the duty cycle will get reset to 0.1%.
//
//*****************************************************************************
int main(void)
{
SysCtlClockSet(SYSCTL_SYSDIV_4 | SYSCTL_USE_PLL| SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ);
SysCtlPWMClockSet(SYSCTL_PWMDIV_1);
SysCtlPeripheralEnable(SYSCTL_PERIPH_PWM1);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE); // connector J1, pin PE4 and PE5
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF); // connector J3, pin PD0 and PD1

// GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, GPIO_PIN_3|GPIO_PIN_2|GPIO_PIN_1);

GPIOPinTypePWM(GPIO_PORTD_BASE, GPIO_PIN_0);
GPIOPinConfigure(GPIO_PD0_M1PWM0);

// PWM PD1, motor B
GPIOPinTypePWM(GPIO_PORTD_BASE, GPIO_PIN_1);
GPIOPinConfigure(GPIO_PD1_M1PWM1);

// PWM PE4, motor C
GPIOPinTypePWM(GPIO_PORTE_BASE, GPIO_PIN_4);
GPIOPinConfigure(GPIO_PE4_M1PWM2);

// PWM PE5, motor D
GPIOPinTypePWM(GPIO_PORTE_BASE, GPIO_PIN_5);
GPIOPinConfigure(GPIO_PE5_M1PWM3);

PWMGenConfigure(PWM1_BASE, PWM_GEN_0,PWM_GEN_MODE_DOWN );
PWMGenConfigure(PWM1_BASE, PWM_GEN_1,PWM_GEN_MODE_DOWN );


PWMGenPeriodSet(PWM1_BASE, PWM_GEN_0, 60);
PWMGenPeriodSet(PWM1_BASE, PWM_GEN_1, 60);

PWMPulseWidthSet(PWM1_BASE, PWM_OUT_0, 30);
PWMPulseWidthSet(PWM1_BASE, PWM_OUT_1, 54);



PWMOutputState(PWM1_BASE, PWM_OUT_0_BIT|PWM_OUT_1_BIT, true);
PWMOutputInvert(PWM1_BASE, PWM_OUT_1_BIT, true);



PWMGenEnable(PWM1_BASE, PWM_GEN_1);
IntMasterEnable();
PWMIntEnable(PWM1_BASE, PWM_INT_GEN_1);
PWMGenIntTrigEnable(PWM1_BASE, PWM_GEN_1,PWM_INT_CNT_LOAD);
// IntEnable(INT_PWM1_1);

////ADC Configuration
ADCSequenceConfigure(ADC0_BASE, 3, ADC_TRIGGER_PWM1|ADC_TRIGGER_PWM_MOD1, 0);
ADCSequenceStepConfigure(ADC0_BASE, 3, 0, ADC_CTL_CH0);
ADCSequenceStepConfigure(ADC0_BASE, 3, 1,ADC_CTL_CH1);
ADCSequenceStepConfigure(ADC0_BASE, 3, 2, ADC_CTL_CH2| ADC_CTL_IE | ADC_CTL_END);
ADCSequenceEnable(ADC0_BASE, 3);
ADCIntClear(ADC0_BASE, 3);
ADCIntEnableEx(ADC0_BASE, 3);
PWMGenEnable(PWM1_BASE, PWM_GEN_0|PWM_GEN_1);
while(1)
{

}
}

the problem i am now facing is if i run the code in debug mode i am getting a fault ISR in

ADCSequenceConfigure(ADC0_BASE, 3, ADC_TRIGGER_PWM1|ADC_TRIGGER_PWM_MOD1, 0);

this Sequence configure is for triggering the ADC at PWM gen 1 Interrupt , for module 1

i coudnt figure out the problems pls correct me where i have gone wrong

Hi Amith Ashara

i have not enable to the Peripheral enable for ADC now the code is not entering into the fault ISR , i am working on the ADC interrupt will update asap

Hi Amith

i have managed to get the PWM working and ADC interrupt as well here is the code that i have done , i facing only one problem here i able to get the ADC interrupt only for the one step configuration

if i have the step configured ADCSequenceStepConfigure(ADC0_BASE, 3, 0, ADC_CTL_CH0 | ADC_CTL_IE | ADC_CTL_END);

i am able to get the ADC interrupt but if i configured 3 channels like below my interrupt is not generating

ADCSequenceStepConfigure(ADC0_BASE, 3, 0, ADC_CTL_CH0);
ADCSequenceStepConfigure(ADC0_BASE, 3, 1, ADC_CTL_CH1);
ADCSequenceStepConfigure(ADC0_BASE, 3, 2, ADC_CTL_CH2 | ADC_CTL_IE | ADC_CTL_END);


for the forum reference i am attaching the full code again

#include <stdbool.h>
#include <stdint.h>
#include "inc/hw_ints.h"
#include "inc/hw_memmap.h"
#include "driverlib/gpio.h"
#include "driverlib/interrupt.h"
#include "driverlib/pin_map.h"
#include "driverlib/pwm.h"
#include "driverlib/sysctl.h"
#include "driverlib/uart.h"
#include "utils/uartstdio.h"
#include "driverlib/adc.h"

int Count,PWM_FREQUENCY,ui8Adjust,ui32Load, ui32PWMClock,FLAG_ADC;
uint32_t ui32ADC0Value[4];
//*****************************************************************************
//
// The interrupt handler for the for PWM0 interrupts.
//
//*****************************************************************************
void
PWM0IntHandler(void)
{
if(FLAG_ADC==0)ADCProcessorTrigger(ADC0_BASE, 3);
while(!ADCIntStatus(ADC0_BASE, 3, false))
{
FLAG_ADC=1;
}
if(FLAG_ADC==1)
{


}

}

void ADCIntHandler(void)
{
ADCIntClear(ADC0_BASE, 3);
ADCSequenceDataGet(ADC0_BASE, 3, ui32ADC0Value);
FLAG_ADC = 0;

}

//*****************************************************************************
//
// Configure PWM0 for a load interrupt. This interrupt will trigger everytime
// the PWM0 counter gets reloaded. In the interrupt, 0.1% will be added to
// the current duty cycle. This will continue until a duty cycle of 75% is
// received, then the duty cycle will get reset to 0.1%.
//
//*****************************************************************************
int main(void)
{
SysCtlClockSet(SYSCTL_SYSDIV_4 | SYSCTL_USE_PLL| SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ);
SysCtlPWMClockSet(SYSCTL_PWMDIV_1);
SysCtlPeripheralEnable(SYSCTL_PERIPH_PWM1);
SysCtlPeripheralEnable(SYSCTL_PERIPH_ADC0);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE); // connector J1, pin PE4 and PE5
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF); // connector J3, pin PD0 and PD1
GPIOPinTypeADC(GPIO_PORTE_BASE, GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2);
// GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, GPIO_PIN_3|GPIO_PIN_2|GPIO_PIN_1);

GPIOPinTypePWM(GPIO_PORTD_BASE, GPIO_PIN_0);
GPIOPinConfigure(GPIO_PD0_M1PWM0);

// PWM PD1, motor B
GPIOPinTypePWM(GPIO_PORTD_BASE, GPIO_PIN_1);
GPIOPinConfigure(GPIO_PD1_M1PWM1);

// PWM PE4, motor C
GPIOPinTypePWM(GPIO_PORTE_BASE, GPIO_PIN_4);
GPIOPinConfigure(GPIO_PE4_M1PWM2);

// PWM PE5, motor D
GPIOPinTypePWM(GPIO_PORTE_BASE, GPIO_PIN_5);
GPIOPinConfigure(GPIO_PE5_M1PWM3);

PWMGenConfigure(PWM1_BASE, PWM_GEN_0,PWM_GEN_MODE_DOWN );
PWMGenConfigure(PWM1_BASE, PWM_GEN_1,PWM_GEN_MODE_DOWN );


PWMGenPeriodSet(PWM1_BASE, PWM_GEN_0, 60);
PWMGenPeriodSet(PWM1_BASE, PWM_GEN_1, 60);

PWMPulseWidthSet(PWM1_BASE, PWM_OUT_0, 30);
PWMPulseWidthSet(PWM1_BASE, PWM_OUT_1, 54);



PWMOutputState(PWM1_BASE, PWM_OUT_0_BIT|PWM_OUT_1_BIT, true);
PWMOutputInvert(PWM1_BASE, PWM_OUT_1_BIT, true);


PWMGenEnable(PWM1_BASE, PWM_GEN_0);
PWMGenEnable(PWM1_BASE, PWM_GEN_1);

PWMIntEnable(PWM1_BASE, PWM_INT_GEN_1);
PWMGenIntTrigEnable(PWM1_BASE, PWM_GEN_1,PWM_INT_CNT_LOAD);

////ADC Configuration
ADCSequenceConfigure(ADC0_BASE,3,ADC_TRIGGER_PROCESSOR, 0);
ADCSequenceStepConfigure(ADC0_BASE, 3, 0, ADC_CTL_CH0);
ADCSequenceStepConfigure(ADC0_BASE, 3, 1, ADC_CTL_CH1);
ADCSequenceStepConfigure(ADC0_BASE, 3, 2, ADC_CTL_CH2 | ADC_CTL_IE | ADC_CTL_END);
ADCSequenceEnable(ADC0_BASE, 3);
ADCIntClear(ADC0_BASE, 3);
ADCIntEnable(ADC0_BASE, 3);
IntEnable(INT_ADC0SS3);
PWMGenEnable(PWM1_BASE, PWM_GEN_0|PWM_GEN_1);
IntEnable(INT_PWM1_1);
IntMasterEnable();
while(1)
{


}
}


pls clarify

Vijayanarayana R said:

PWMGenPeriodSet(PWM1_BASE, PWM_GEN_0, 60);
PWMGenPeriodSet(PWM1_BASE, PWM_GEN_1, 60);

With your PWM clock set as: "SysCtlPWMClockSet(SYSCTL_PWMDIV_1);"

and your 2 digit PWM Period - you've set your PWM frequency extremely high.   

Why have you done that?    And what are the likely consequences of so high a PWM frequency?

I AM TRYING TO GET DATA FROM A cis SENSOR DATA

VR,

Remain curious how did you get the PWM load count interrupt to trigger the ADC sample sequencer with your source code?  

Please explain how the interrupt hander for sequencer 3 is now being called by your source code.

Perhaps your source PWM is not properly configured?

PWMGenIntTrigEnable(PWM0_BASE, PWM_GEN_0, PWM_INT_CNT_LOAD);

ADCSequenceConfigure(ADC0_BASE, 3, ADC_TRIGGER_PWM0 , 0);

VR,

>I have got the output i have wrongly set the sample sequencer thanks for the help provided now i am able to get 3 channel sample

Yet who alerted you only to later see self awarded answer flag? Never look back thank all helpers for making you aware of configuration issue :(