ICM20948 multi device addressing problem

Sensors IMU & Motion
1

Hi to everybody,

i am developing a system based on ICM 20948 IMU devices programmed with library “SparkFun_9DoF_IMU_Breakout_-ICM_20948-_Arduino_Library” ver. 1.2.11.

It is working properly with one device only and quaternions as output.

We need now for our project to use more devices together addressed by SPI, but it doesn’t work and even if addressed with different CS no device answers in this case. Do you have any suggestions to help us to solve this problem?

Thank you in advance for your support

2

Do you have one device working with SPI, or was that I2C? If the latter, verify that one device works with SPI.

Please post the code, using code tags, and a clear, complete wiring diagram, with pins and connections clearly labeled.

3

This is the code (it is an example from SparkFun_9DoF_IMU_Breakout_-ICM_20948-_Arduino_Library https://github.com/sparkfun/SparkFun_IC … PITest.ino ):

#include "ICM_20948.h" // Click here to get the library: http://librarymanager/All#SparkFun_ICM_20948_IMU

#define SERIAL_PORT Serial

#define SPI_PORT SPI // Your desired SPI port.
#define CS_PIN_1 7   // Which pin you connect CS to for Sensor 1
#define CS_PIN_2 6   // Which pin you connect CS to for Sensor 2

ICM_20948_SPI myICM1; // Create an ICM_20948_SPI object
ICM_20948_SPI myICM2; // Create an ICM_20948_SPI object

void setup()
{

  SERIAL_PORT.begin(115200);
  while (!SERIAL_PORT)
  {
  };

  SPI_PORT.begin();

  myICM1.enableDebugging(); // Uncomment this line to enable helpful debug messages on Serial
  myICM2.enableDebugging(); // Uncomment this line to enable helpful debug messages on Serial

  bool initialized = false;
  while (!initialized)
  {

    myICM1.begin(CS_PIN_1, SPI_PORT);

    SERIAL_PORT.print(F("Initialization of sensor 1 returned: "));
    SERIAL_PORT.println(myICM1.statusString());
    if (myICM1.status != ICM_20948_Stat_Ok)
    {
      SERIAL_PORT.println(F("Trying again..."));
      delay(500);
    }
    else
    {
      initialized = true;
    }
  }

  initialized = false;
  while (!initialized)
  {

    myICM2.begin(CS_PIN_2, SPI_PORT);

    SERIAL_PORT.print(F("Initialization of sensor 2 returned: "));
    SERIAL_PORT.println(myICM1.statusString());
    if (myICM2.status != ICM_20948_Stat_Ok)
    {
      SERIAL_PORT.println(F("Trying again..."));
      delay(500);
    }
    else
    {
      initialized = true;
    }
  }
}

bool dataSeen = false;

void loop()
{

  if (myICM1.dataReady())
  {
    myICM1.getAGMT(); // The values are only updated when you call 'getAGMT'
    SERIAL_PORT.print("Sensor 1: ");
    //printRawAGMT( myICM1.agmt);
    printScaledAGMT(&myICM1);
    dataSeen = true;
  }
  if (myICM2.dataReady())
  {
    myICM2.getAGMT(); // The values are only updated when you call 'getAGMT'
    SERIAL_PORT.print("Sensor 2: ");
    //printRawAGMT( myICM2.agmt );
    printScaledAGMT(&myICM2);
    dataSeen = true;
  }
  if (dataSeen)
  {
    delay(30);
    dataSeen = false;
  }
  else
  {
    SERIAL_PORT.println("Waiting for data");
    delay(500);
  }
}

// Below here are some helper functions to print the data nicely!

void printPaddedInt16b(int16_t val)
{
  if (val > 0)
  {
    SERIAL_PORT.print(" ");
    if (val < 10000)
    {
      SERIAL_PORT.print("0");
    }
    if (val < 1000)
    {
      SERIAL_PORT.print("0");
    }
    if (val < 100)
    {
      SERIAL_PORT.print("0");
    }
    if (val < 10)
    {
      SERIAL_PORT.print("0");
    }
  }
  else
  {
    SERIAL_PORT.print("-");
    if (abs(val) < 10000)
    {
      SERIAL_PORT.print("0");
    }
    if (abs(val) < 1000)
    {
      SERIAL_PORT.print("0");
    }
    if (abs(val) < 100)
    {
      SERIAL_PORT.print("0");
    }
    if (abs(val) < 10)
    {
      SERIAL_PORT.print("0");
    }
  }
  SERIAL_PORT.print(abs(val));
}

void printRawAGMT(ICM_20948_AGMT_t agmt)
{
  SERIAL_PORT.print("RAW. Acc [ ");
  printPaddedInt16b(agmt.acc.axes.x);
  SERIAL_PORT.print(", ");
  printPaddedInt16b(agmt.acc.axes.y);
  SERIAL_PORT.print(", ");
  printPaddedInt16b(agmt.acc.axes.z);
  SERIAL_PORT.print(" ], Gyr [ ");
  printPaddedInt16b(agmt.gyr.axes.x);
  SERIAL_PORT.print(", ");
  printPaddedInt16b(agmt.gyr.axes.y);
  SERIAL_PORT.print(", ");
  printPaddedInt16b(agmt.gyr.axes.z);
  SERIAL_PORT.print(" ], Mag [ ");
  printPaddedInt16b(agmt.mag.axes.x);
  SERIAL_PORT.print(", ");
  printPaddedInt16b(agmt.mag.axes.y);
  SERIAL_PORT.print(", ");
  printPaddedInt16b(agmt.mag.axes.z);
  SERIAL_PORT.print(" ], Tmp [ ");
  printPaddedInt16b(agmt.tmp.val);
  SERIAL_PORT.print(" ]");
  SERIAL_PORT.println();
}

void printFormattedFloat(float val, uint8_t leading, uint8_t decimals)
{
  float aval = abs(val);
  if (val < 0)
  {
    SERIAL_PORT.print("-");
  }
  else
  {
    SERIAL_PORT.print(" ");
  }
  for (uint8_t indi = 0; indi < leading; indi++)
  {
    uint32_t tenpow = 0;
    if (indi < (leading - 1))
    {
      tenpow = 1;
    }
    for (uint8_t c = 0; c < (leading - 1 - indi); c++)
    {
      tenpow *= 10;
    }
    if (aval < tenpow)
    {
      SERIAL_PORT.print("0");
    }
    else
    {
      break;
    }
  }
  if (val < 0)
  {
    SERIAL_PORT.print(-val, decimals);
  }
  else
  {
    SERIAL_PORT.print(val, decimals);
  }
}

void printScaledAGMT(ICM_20948_SPI *sensor)
{
  SERIAL_PORT.print("Scaled. Acc (mg) [ ");
  printFormattedFloat(sensor->accX(), 5, 2);
  SERIAL_PORT.print(", ");
  printFormattedFloat(sensor->accY(), 5, 2);
  SERIAL_PORT.print(", ");
  printFormattedFloat(sensor->accZ(), 5, 2);
  SERIAL_PORT.print(" ], Gyr (DPS) [ ");
  printFormattedFloat(sensor->gyrX(), 5, 2);
  SERIAL_PORT.print(", ");
  printFormattedFloat(sensor->gyrY(), 5, 2);
  SERIAL_PORT.print(", ");
  printFormattedFloat(sensor->gyrZ(), 5, 2);
  SERIAL_PORT.print(" ], Mag (uT) [ ");
  printFormattedFloat(sensor->magX(), 5, 2);
  SERIAL_PORT.print(", ");
  printFormattedFloat(sensor->magY(), 5, 2);
  SERIAL_PORT.print(", ");
  printFormattedFloat(sensor->magZ(), 5, 2);
  SERIAL_PORT.print(" ], Tmp (C) [ ");
  printFormattedFloat(sensor->temp(), 5, 2);
  SERIAL_PORT.print(" ]");
  SERIAL_PORT.println();
}

In attach the wiring diagram

ICM 20948 connections.png
ICM 20948 connections.png867×430 8.23 KB