Trigger ADC with Timer

[e174]

I'm trying to trigger an ADC channel with a Timer, but it isn't working. Could you tell me where is the mistake? I'm using an LPC4337.

This is the code :

#include "board.h"


/************ ADC setup ************/

void ADC_setup(void) {

     Chip_SCU_ADC_Channel_Config(0, ADC_CH1);

     static ADC_CLOCK_SETUP_T ADCSetup;

     Chip_ADC_Init(LPC_ADC0, &ADCSetup);

     Chip_ADC_EnableChannel(LPC_ADC0, ADC_CH1, ENABLE);

     Chip_ADC_SetSampleRate(LPC_ADC0, &ADCSetup, ADC_MAX_SAMPLE_RATE);

     Chip_ADC_SetResolution(LPC_ADC0, &ADCSetup, ADC_10BITS);

     Chip_ADC_SetStartMode(LPC_ADC0, ADC_START_ON_CTOUT15, ADC_TRIGGERMODE_RISING);

     Chip_ADC_SetBurstCmd(LPC_ADC0, DISABLE);

     Chip_ADC_Int_SetChannelCmd(LPC_ADC0, ADC_CH1, ENABLE);

}

uint16_t data = 0;

void ADC0_IRQHandler(void) {

     if(Chip_ADC_ReadStatus(LPC_ADC0, ADC_CH1, ADC_DR_OVERRUN_STAT) == SET){

          printf("ADC OVERRUN\n");

     }

     Chip_ADC_ReadValue(LPC_ADC0, ADC_CH1, &data);

     printf("Enter ADC0_IRQHandler()\n");

}

/************ TIMER setup ************/

#define TICKRATE_HZ                     50000

#define LPC_TIMER                          LPC_TIMER3
#define NVIC_TIMER_IRQ                     TIMER3_IRQn
#define TIMER_IRQHandler                void TIMER3_IRQHandler(void)

#define CHIP_RGU_TIMER_RST                RGU_TIMER3_RST
#define CHIP_CLK_TIMER                    CLK_MX_TIMER3

#define LPC_TIMER_MATCH_INT_NUM      3

void TIMER_setup(){

     Chip_TIMER_Init(LPC_TIMER);

     Chip_RGU_TriggerReset(CHIP_RGU_TIMER_RST);

     while (Chip_RGU_InReset(CHIP_RGU_TIMER_RST)) {}

     uint32_t timerFreq = Chip_Clock_GetRate(CHIP_CLK_TIMER);

     Chip_TIMER_Reset(LPC_TIMER);

     Chip_TIMER_MatchEnableInt(LPC_TIMER, LPC_TIMER_MATCH_INT_NUM);

     Chip_TIMER_SetMatch(LPC_TIMER, LPC_TIMER_MATCH_INT_NUM, (timerFreq / TICKRATE_HZ));

     Chip_TIMER_ResetOnMatchEnable(LPC_TIMER, LPC_TIMER_MATCH_INT_NUM);

     Chip_TIMER_ExtMatchControlSet(LPC_TIMER, 1, TIMER_EXTMATCH_TOGGLE, LPC_TIMER_MATCH_INT_NUM);

     Chip_TIMER_Enable(LPC_TIMER);

}

TIMER_IRQHandler {

     if (Chip_TIMER_MatchPending(LPC_TIMER, LPC_TIMER_MATCH_INT_NUM)) {

          Chip_TIMER_ClearMatch(LPC_TIMER, LPC_TIMER_MATCH_INT_NUM);

     }

     //printf("Enter TIMER_IRQHandler()\n");

}

/************ main() ************/

int main(void)
{
     SystemCoreClockUpdate();

     Board_Init();

     ADC_setup();

     TIMER_setup();

     NVIC_EnableIRQ(ADC0_IRQn);
     NVIC_ClearPendingIRQ(ADC0_IRQn);

     NVIC_EnableIRQ(NVIC_TIMER_IRQ);
     NVIC_ClearPendingIRQ(NVIC_TIMER_IRQ);

     while(1) {

          __WFI();

     }

     return 1;
}‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

[fabian_nardone]

Hello, I am trying to implement your code, copy and paste it, adding the line of code that you said solved the problem, the interruption of the timer works correctly, but the adc never interrupts, are there any more details that you could clarify? Thank you!

[mike-dekoker]

Just in case anyone else runs into this, the EDGE bit (0x2) also needs to be set in order to the trigger the ADC.

LPC_GIMA->ADCSTART0_IN = 0x6;

[e174]

I found the solution reading the chapter about GIMA:

So, what worked for me was to add the following line:

LPC_GIMA->ADCSTART0_IN = 0x4;‍‍