CCS/TM4C1294NCPDT: TM4C1294 ADC sample problems

Tool/software: Code Composer Studio

Hi together,

i want to convert 3 analog inputs over 1 sequencer with the following settings.

When I debug my code, than it look like I have a problem with the FIFO.

With the first Interrupt there were stored 3 values in the “adcBuffer2” variable. And in the next interrupts the adcBuffer2 stored 6 values. I don’t understand why this happened.

Have you any idears?

//
// Library Generals
//
#include "stdbool.h"
#include <stdio.h>
#include <stdint.h>

//
// Library TivaWare
//
#include "driverlib/sysctl.h"
#include "driverlib/interrupt.h"
#include "driverlib/adc.h"
#include "inc/tm4c1294ncpdt.h"
#include "inc/hw_memmap.h"

//
// Library own
//
#include "adc2.h"

//
// Globale Variablen
//
uint32_t adcBuffer2[30];
uint32_t adcGetValues;

//
// Interrupt Handler ADC0SS0
//
void ADC0IntHandler(void) {
	uint32_t test = 0;


	// Clear interrupt Flag
	ADCIntClear(ADC0_BASE, 0);

	ADCSequenceDataGet(ADC0_BASE, 0, adcBuffer2);


	adcGetValues=1;


}


void main(void) {

	adcGetValues=0;


	uint32_t sysclock_read=0;
	sysclock_read=SysCtlClockFreqSet(SYSCTL_OSC_INT | SYSCTL_USE_PLL | SYSCTL_CFG_VCO_480, 120000000);
	printf("Systemclock is set to: %d\n", sysclock_read);

	// ADC Init
	adc2_init();


	IntPrioritySet(INT_ADC0SS0, 0x00);

	//
	// ADC0SS0 Interrupt source
	//
	ADCIntRegister(ADC0_BASE, 0, ADC0IntHandler);

	//
	// Register Interrupt to NVIC
	//
	IntRegister(INT_ADC0SS0, ADC0IntHandler);

	//
	// ADC0 enable
	//
	ADCIntEnable(ADC0_BASE, 0);



	//
	// Interrupt ADC0SS0 enable
	//
	IntEnable(INT_ADC0SS0);

	//
	// Enable Global Interrupts
	//
	IntMasterEnable();

	//
	// Sequencer enable
	//
	ADCSequenceEnable(ADC0_BASE, 0);

	while(1){


		if (adcGetValues==1) {
			ADCSequenceDisable(ADC0_BASE, 0);
			ADCIntDisable(ADC0_BASE, 0);
			IntDisable(INT_ADC0SS0);

			//ADCSequenceDisable(ADC0_BASE, 0);


/*
			printf("ADC Value1: %d\n", adcBuffer2[0]);
			printf("ADC Value2: %d\n", adcBuffer2[1]);
			printf("ADC Value3: %d\n", adcBuffer2[2]);
*/
			adcGetValues = 0;

			ADCIntEnable(ADC0_BASE, 0);
			IntEnable(INT_ADC0SS0);
			ADCSequenceEnable(ADC0_BASE, 0);


		}


	}

}

#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>

#include "inc/tm4c1294ncpdt.h"
#include "inc/hw_memmap.h"
#include "driverlib/sysctl.h"
#include "driverlib/adc.h"
#include "driverlib/gpio.h"
#include "driverlib/comp.h"

#include "func.h"



adc2_init(){

	uint32_t adcClock=0, adcDiv=0;

	//
	// Enable the ADC0 peripheral
	//
	SysCtlPeripheralEnable(SYSCTL_PERIPH_ADC0); wait();

	SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE); wait();
	GPIOPinTypeADC(GPIO_PORTE_BASE, GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3);

	//
	// Configure the ADC to use PLL at 480 MHz with Full rate devided by 30 to get 16 MHz
	//
	ADCClockConfigSet(ADC0_BASE, ADC_CLOCK_SRC_PLL | ADC_CLOCK_RATE_FULL, 30);

	ADCSequenceDisable(ADC0_BASE, 0);

	//
	// Read the current ADC configuration
	//
	adcClock=ADCClockConfigGet(ADC0_BASE, &adcDiv);
	printf("ADC clock is: 0x%x, div: 0x%x\n", adcClock, adcDiv);

	//
	// Hardware averageing: by a faktor of 2 -> 2,4,8,16,32,64
	//
	ADCHardwareOversampleConfigure(ADC0_BASE, 0);

	//
	// ADC voltage-lvl reference set to intern
	//
	ADCReferenceSet(ADC0_BASE, ADC_REF_INT);

	//
	// ADC Sequencer config: Source ADC0, Sequencer 0, Trigger: always, priority: 0
	//
	ADCSequenceConfigure(ADC0_BASE, 0, ADC_TRIGGER_ALWAYS, 0);

	//
	// ADC Sequencer step
	// 1. Source-ADC -> ADC0_BASE
	// 2. Source-Sequencer -> 0
	// 3. Sample-Value depends in the depth of the FIFO, by Sequencer 0 it is up to 7 (0-7)
	// 4. Config-> select input-channel AINx, interrupt specification
	//
	ADCSequenceStepConfigure(ADC0_BASE, 0, 0, ADC_CTL_CH0);
	ADCSequenceStepConfigure(ADC0_BASE, 0, 1, ADC_CTL_CH1);
	ADCSequenceStepConfigure(ADC0_BASE, 0, 2, (ADC_CTL_CH2 | ADC_CTL_IE | ADC_CTL_END));

}