Arduino Compatibility

[uljad]

Hello, is there any chance the ADC code can be Arduino Nano BLE compatible?

[andenoremode]

Hi, I'm not too familiar with the Arduino development environment. If it gives you access to the CMSIS style header files then it should be compatible. But Arduino probably gives you some wrapper to use the ADC?

[uljad]

Thank you for your email. Arduino lets me convert but I nees at about 20ksps and Arduino is too slow. The registers interface should work but I am running into troubles. I raised an issue here https://devzone.nordicsemi.com/f/nordic-q-a/73829/how-do-i-use-registers-to-configure-saadc-for-my-arduino-nano-33

On Tue, Apr 13, 2021 at 10:34 AM andenoremode @.***> wrote:

Hi, I'm not too familiar with the Arduino development environment. If it gives you access to the CMSIS style header files then it should be compatible. But Arduino probably gives you some wrapper to use the ADC?

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/andenore/NordicSnippets/issues/26#issuecomment-818478554, or unsubscribe https://github.com/notifications/unsubscribe-auth/AMV7B6IUKIP3G4665KZAF5DTIPQV5ANCNFSM42YRQGSQ .

[uljad]

#include <Arduino.h>
#include <nrf.h>

 volatile uint32_t result = 0;
 volatile uint32_t result_channel;
 volatile uint32_t amount =0;
  float precise_result = 0;

void setup() {

  Serial.begin(9600);

  // Start HFCLK from crystal oscillator, this will give the SAADC higher accuracy
  NRF_CLOCK->TASKS_HFCLKSTART = 1;
  while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0);
  NRF_CLOCK->EVENTS_HFCLKSTARTED = 0;

  // Configure SAADC singled-ended channel, Internal reference (0.6V) and 1/6 gain.
  NRF_SAADC->CH[0].CONFIG = (SAADC_CH_CONFIG_GAIN_Gain1_6    << SAADC_CH_CONFIG_GAIN_Pos) |
                            (SAADC_CH_CONFIG_MODE_SE         << SAADC_CH_CONFIG_MODE_Pos) |
                            (SAADC_CH_CONFIG_REFSEL_Internal << SAADC_CH_CONFIG_REFSEL_Pos) |
                            (SAADC_CH_CONFIG_RESN_Bypass     << SAADC_CH_CONFIG_RESN_Pos) |
                            (SAADC_CH_CONFIG_RESP_Bypass     << SAADC_CH_CONFIG_RESP_Pos) |
                            (SAADC_CH_CONFIG_TACQ_3us        << SAADC_CH_CONFIG_TACQ_Pos);

  // Configure the SAADC channel with VDD as positive input, no negative input(single ended).
  NRF_SAADC->CH[0].PSELP = SAADC_CH_PSELP_PSELP_AnalogInput1 << SAADC_CH_PSELP_PSELP_Pos;
  NRF_SAADC->CH[0].PSELN = SAADC_CH_PSELN_PSELN_NC << SAADC_CH_PSELN_PSELN_Pos;

  // Configure the SAADC resolution.
  NRF_SAADC->RESOLUTION = SAADC_RESOLUTION_VAL_14bit << SAADC_RESOLUTION_VAL_Pos;

  // Configure result to be put in RAM at the location of "result" variable.
  NRF_SAADC->RESULT.MAXCNT = 1;
  NRF_SAADC->RESULT.PTR = (uint32_t)&result;

  // No automatic sampling, will trigger with TASKS_SAMPLE.
  NRF_SAADC->SAMPLERATE = SAADC_SAMPLERATE_MODE_Task << SAADC_SAMPLERATE_MODE_Pos;

  // Enable SAADC (would capture analog pins if they were used in CH[0].PSELP)
  NRF_SAADC->ENABLE = SAADC_ENABLE_ENABLE_Enabled << SAADC_ENABLE_ENABLE_Pos;

  // Calibrate the SAADC (only needs to be done once in a while)
  NRF_SAADC->TASKS_CALIBRATEOFFSET = 1;
  while (NRF_SAADC->EVENTS_CALIBRATEDONE == 0);
  NRF_SAADC->EVENTS_CALIBRATEDONE = 0;
  while (NRF_SAADC->STATUS == (SAADC_STATUS_STATUS_Busy <<SAADC_STATUS_STATUS_Pos));

  // Start the SAADC and wait for the started event.
  NRF_SAADC->TASKS_START = 1;
  while (NRF_SAADC->EVENTS_STARTED == 0);
  NRF_SAADC->EVENTS_STARTED = 0;

  // Do a SAADC sample, will put the result in the configured RAM buffer.
  NRF_SAADC->TASKS_SAMPLE = 1;
  while (NRF_SAADC->EVENTS_END == 0);
  NRF_SAADC->EVENTS_END = 0;

  // // Convert the result to voltage
  // // Result = [V(p) - V(n)] * GAIN/REFERENCE * 2^(RESOLUTION)
  // // Result = (VDD - 0) * ((1/6) / 0.6) * 2^14
  // // VDD = Result / 4551.1
  // precise_result = (float)result / 4551.1f;
  // precise_result; // to get rid of set but not used warning

  // // Stop the SAADC, since it's not used anymore.
  // NRF_SAADC->TASKS_STOP = 1;
  // while (NRF_SAADC->EVENTS_STOPPED == 0);
  // NRF_SAADC->EVENTS_STOPPED = 0;

}

void loop() {

  Serial.println("Measure1");

  // Convert the result to voltage
  // Result = [V(p) - V(n)] * GAIN/REFERENCE * 2^(RESOLUTION)
  // Result = (VDD - 0) * ((1/6) / 0.6) * 2^14
  // VDD = Result / 4551.1
  result = NRF_SAADC->RESULT.PTR;
  result_channel = result & 0xFFFF0000;
  precise_result =result_channel/4551.1;

  Serial.println("===============");
  // Serial.println(SAADC_CH_PSELN_PSELN_AnalogInput0);
  Serial.println(result,HEX);
  Serial.println(precise_result);
  Serial.println(NRF_SAADC->RESULT.AMOUNT);
  Serial.println();

  // //Stop the SAADC, since it's not used anymore.
  // NRF_SAADC->TASKS_STOP = 1;
  // while (NRF_SAADC->EVENTS_STOPPED == 0);
  // NRF_SAADC->EVENTS_STOPPED = 0;

  //   while (1)
  // {
  //   __WFE();
  // }

}