• State Resolved
  • Locked Locked
  • Replies 9 replies
  • Subscribers 30 subscribers
  • Views 774 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TM4C123GH6PM: cannot make ADC0 SS3 work at interrupt mode

Mohamed Samy
Prodigy 110 points
Part Number: TM4C123GH6PM

Hi,

I tried to configure TivaC to work with ADC in interrupt mode but it doesn't work

bit 3 in ADCIM for ADC0 is set, bit 2 in ADCSSCTL3 for ADC0 is set, bit 17 in EN0 is set.

also all required registers are set to make ADC0 work and i tested then by working polling based and i worked fine.

What should i do also to make it works ?

Thanks.

  • 0
    TI__Guru 72500 points
    Your problem description is too vague for me to offer specific help. In general you must either register the interrupt service routine with the function IntRegister() or edit the startup_ccs.c file to make the ADC Sequence 3 vector (line107) to point to your interrupt routine instead of "IntDefaultHandler". You need to enable the master interrupts with a call to IntMasterEnable(), and you need to enable the ADC0 sequence 3 interrupt with a call to IntEnable(INT_ADC0SS3).
  • 0 in reply to Bob Crosby
    Prodigy 110 points
    line 107 is // Timer 1 subtimer A did you mean line 103 (// ADC Sequence 3)?
    i didn't change IntDefaultHandler and i wait for the system to enter while(1) to make sure that is working then i will change it
    which header file include this function IntMasterEnable() ?
    and which one for this function IntEnable(INT_ADC0SS3) ?
  • 0 in reply to Mohamed Samy
    TI__Guru 72500 points

    Yes, sorry. I mean the line for ADC Sequence 3. The line numbers will change as you will also need to add  a function prototype for your interrupt routine line  like:

    extern void MyADC0Seq3IntRoutine(void);

    Add these two header files:

    #include "inc/hw_ints.h"
#include "driverlib/interrupt.h"

  • 0 in reply to Bob Crosby
    Prodigy 110 points

    Bob Crosby said:
    #include "inc/hw_ints.h"
#include "driverlib/interrupt.h"



    I am working code composer and these two header files cannot be found so should i download them or what ?
  • 0 in reply to Mohamed Samy
    TI__Guru 72500 points

    These header files are part of TivaWare. The default installation location of the latest version of TivaWare is:
    C:\ti\TivaWare_C_Series-2.1.4.178

  • 0 in reply to Bob Crosby
    Prodigy 110 points

    I downloaded TivaWare, installed it and used this code from internet

    #include <stdint.h>
#include <stdbool.h>
#include "inc/hw_memmap.h""
#include "inc/hw_types.h"
#include "inc/tm4c123gh6pm.h"
#include "driverlib/pin_map.h"
#include "driverlib/sysctl.h"
#include "driverlib/debug.h"
#include "driverlib/gpio.h"
#include "driverlib/adc.h"
#include "driverlib/rom.h"
#include "driverlib/timer.h"
#include "driverlib/interrupt.h"

const int sampleFreq = 8000;

uint32_t ADC0Value[1];
uint16_t samplePeriod;

uint8_t x = 0;

void systemSetup(void){
    // *** Clock
    ROM_SysCtlClockSet(SYSCTL_SYSDIV_2_5|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN);

    // *** Peripheral Enable
    ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_ADC0);
    ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER0);
    ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);

    // *** ADC0
    ROM_ADCHardwareOversampleConfigure(ADC0_BASE,4);
    ROM_ADCReferenceSet(ADC0_BASE,ADC_REF_INT);
    ROM_ADCSequenceConfigure(ADC0_BASE,3,ADC_TRIGGER_TIMER,0);
    ROM_ADCSequenceStepConfigure(ADC0_BASE,3,0,ADC_CTL_CH7|ADC_CTL_IE|ADC_CTL_END);
    ROM_ADCSequenceEnable(ADC0_BASE,3);

    // *** Timer0
    ROM_TimerConfigure(TIMER0_BASE,TIMER_CFG_PERIODIC);
    samplePeriod = ROM_SysCtlClockGet()/sampleFreq;
    ROM_TimerLoadSet(TIMER0_BASE,TIMER_A,samplePeriod - 1);
    ROM_TimerControlTrigger(TIMER0_BASE,TIMER_A,true);

    // *** GPIO
    ROM_GPIOPinTypeADC(GPIO_PORTD_BASE,GPIO_PIN_0);

    // *** Interrupts
    ROM_IntEnable(INT_TIMER0A);
    ROM_TimerIntEnable(TIMER0_BASE,TIMER_TIMA_TIMEOUT);
    ROM_IntEnable(INT_ADC0SS3);
    ROM_ADCIntEnable(ADC0_BASE,3);

    ROM_IntMasterEnable();
    ROM_TimerEnable(TIMER0_BASE,TIMER_A);
}

int main(void)
{

    systemSetup();

    while(1)
    {

    }

    return 0;
}

void Timer0IntHandler(void){
    ROM_TimerIntClear(TIMER0_BASE, TIMER_TIMA_TIMEOUT);


}

void ADC0SS3IntHandler(void){
    x++;
    ROM_ADCIntClear(ADC0_BASE,3);

    ROM_ADCSequenceDataGet(ADC0_BASE,3,ADC0Value); // Get Data from ADC and store it in ADC0Value
}

    i expected while running the code x increase with time but it remains at 0 why?

    i added Timer0IntHandler at Timer 0 Subtimer A and ADC0SS3IntHandler at ADC Sequence 3

  • 0 in reply to Mohamed Samy
    TI__Guru*** 128125 points

    Hello Mohamed,

    You need to declare the variable 'x' as a volatile for it to be updated within your ISR. This can be done as follows:

    volatile uint8_t x = 0;

    Please see this E2E post for background as to why this is important when using a global variable within an ISR: e2e.ti.com/.../2550611

  • 0 in reply to Ralph Jacobi
    Prodigy 110 points

    aha i forgot to do that but also after i made it volatile i expected to run the chip and by tracking x at the debug i should saw it increase by the rate of timer but x didn't change from 0 
    What is the problem ?

    Best Regards.

  • 0 in reply to Ralph Jacobi
    Prodigy 110 points
    Thank you,
    That was the problem.
    Best Regards.