SpresenseとIIS3DWBでの通信ができません

O

OrangeJuice

Spresense+Spresense拡張ボードの環境でIIS3DWBの加速度センサを利用したいと考えています．
事前にArduinoでは動作確認済みのコードを使って，Spresenseで動作させようとしたところ「IIS3DWB not functioning!」と出て，getChipID関数で正しくデバイスのIDが取得できません．
ソースコードを添付しますので，何かお気づきの点があればご助言いただきたいです．

なお，拡張ボードの電圧設定は5V，IIS3DWBとSpresenseの結線は以下の通りです．

SpresenseIIS3DWB
3.3V3.3V
SPI CS(D10)SS
SPI MOSI(D11)MOSI
SPI MISO(D12)MISO
SPI SCK(D13)SCK
GNDGND

Code: 
    #include <IIS3DWB.h>
    #include "SPI.h"

    #define SerialDebug true  // set to true to get Serial output for debugging
    #define CSPIN    10

    /* Specify sensor parameters (sample rate is same as the bandwidth 6.3 kHz by default)
     * choices are:  AFS_2G, AFS_4G, AFS_8G, AFS_16G  
    */ 
    uint8_t Ascale = AFS_4G;
    
    float aRes;                              // scale resolutions per LSB for the accel 
    float accelBias[3] = {0.0f, 0.0f, 0.0f}; // offset biases for the accel 
    int16_t IIS3DWBData[4] = {0};                  // Stores the 16-bit signed sensor output
    float ax, ay, az, accelTemp;             // variables to hold latest accel data values 
    uint8_t IIS3DWBstatus;
    
    volatile bool IIS3DWB_DataReady = true, IIS3DWB_Wakeup = true;

    IIS3DWB IIS3DWB(CSPIN); // instantiate IIS3DWB class

    void setup() 
    {
      Serial.begin(115200);
      delay(4000);
    
      SPI.begin(); // Start SPI serial peripheral
      Serial.print("SPI Start!\n");
    
      // Configure SPI ship select for sensor breakout
      pinMode(CSPIN, OUTPUT);
      digitalWrite(CSPIN, HIGH); // disable SPI at start
    
      // Read the IIS3DWB Chip ID register, this is a good test of communication
      Serial.println("IIS3DWB accel...");
      uint8_t c = IIS3DWB.getChipID();  // Read CHIP_ID register for IIS3DWB
      Serial.print("IIS3DWB "); Serial.print("I AM "); Serial.print(c, HEX); Serial.print(" I should be "); Serial.println(0x7B, HEX);
      Serial.println(" ");
    
      if(c == 0x7B) // check if all SPI sensors have acknowledged
      {
       Serial.println("IIS3DWB is online...");  
       Serial.println(" ");
    
       // reset IIS3DWB to start fresh
       IIS3DWB.reset();

       // get accel sensor resolution, only need to do this once
       aRes = IIS3DWB.getAres(Ascale);
    
       IIS3DWB.selfTest();
    
       IIS3DWB.init(Ascale); // configure IIS3DWB  

       IIS3DWB.offsetBias(accelBias);
       Serial.println("accel biases (mg)"); Serial.println(1000.0f * accelBias[0]); Serial.println(1000.0f * accelBias[1]); Serial.println(1000.0f * accelBias[2]);
       Serial.println(" ");
       delay(1000); 
    
      }
      else 
      {
      if(c != 0x6A) Serial.println(" IIS3DWB not functioning!"); 
      while(1){};
      }
    
     }
    /* End of setup */

    void loop() {
      
      if(IIS3DWB_DataReady)  // Handle data ready condition
      {
        IIS3DWBstatus = IIS3DWB.DRstatus(); // read data ready status
        if (IIS3DWBstatus & 0x01) {         // if new accel data is available, read it
          IIS3DWB.readAccelData(IIS3DWBData);  
          // Now we'll calculate the accleration value into actual g's
            ax = (float)IIS3DWBData[0]*aRes - accelBias[0];  // get actual g value, this depends on scale being set
            ay = (float)IIS3DWBData[1]*aRes - accelBias[1];   
            az = (float)IIS3DWBData[2]*aRes - accelBias[2];  
           }
         }  // end of data ready interrupt handlin
 
       // end sensor interrupt handling
        
      if(SerialDebug) { // report latest accel data
        Serial.print("ax = "); Serial.print((int)1000*ax);  
        Serial.print(" ay = "); Serial.print((int)1000*ay); 
        Serial.print(" az = "); Serial.print((int)1000*az); Serial.println(" mg");
        }

      IIS3DWBData[3] = IIS3DWB.readTempData(); // get IIS3DWB chip temperature
      accelTemp = ((float) IIS3DWBData[3]) / 256.0f + 25.0f; // Accel chip temperature in degrees Centigrade
      // Print temperature in degrees Centigrade      
      if(SerialDebug) {
        Serial.print("IIS3DWB temperature is ");  Serial.print(accelTemp, 1);  Serial.println(" degrees C"); // Print T values to tenths of a degree C
        }

    }
    /*  End of main loop */
 

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