I'm trying to write a sketch that will pull data from a BME280 and ADXL345 using the I2C protocol and then write that data to an SD card. Using different sketches I've found online I got something that I think should work, but isn't and I'm not sure what the issue is. During setup, I ask it to create a file HAB Flight Data.txt, write a header then close for later use. I can't even get that to work. Another problem I'm having is my BME sensor not working. I've got both sensors connected on a FeatherWing Proto as follows

Feather      ADXL     BME       
SCL ----->  SCL-----> SCK
SDA------>  SDA-----> SDI
3V------->  VIN-----> VIN
GND------>  GND-----> GND
3V------->  CS

Hardware specs: 1x Feather M0 Adalogger 1x ADXL345 1x BME280 1x FeatherWing Proto

Any insight as to where I went wrong would be much appreciated!

#include <SdFat.h>                 // SD card library
#include <Wire.h>               // I2C wire lbrary
#include <Adafruit_BME280.h>    // Pressure Sensor library
#include <Adafruit_Sensor.h>    // Adafruit Sensor library
#include <Adafruit_ADXL345_U.h> // ADXL345 library

#define SEALEVELPRESSURE_HPA (1013.25)
#define RANGE_2_G 0;

int chipSelect = 4;
float hgInches = 29.97;

SdFat SD;
Adafruit_BME280 bme;
Adafruit_ADXL345_Unified accel = Adafruit_ADXL345_Unified(12345);

void setup() {
  //turn on serial monitor
  while (!Serial) {
  }// end while - serial

  // initialize I2C bus

  bool status;
  //initialize BME sensor
  status =  bme.begin();
  if (!status) {
    Serial.println("No BME");
    while (1);
  } // end if - BME

  //initialize ADXL sensor, range and data rate
  status = accel.begin();
  accel.setRange( ADXL345_RANGE_2_G );
  accel.setDataRate( ADXL345_DATARATE_50_HZ );
  if (!status) {
    Serial.println("No ADXL");
    while (1);
  } // end if - accel

  // initialize the SD card
  Serial.print("Looking for SD: ");
  if (!SD.begin(chipSelect)) {
    Serial.println("SD not found ");
  } // end if - SD
  Serial.println(" SD found");
  // print a header in HAB Flight Data.txt
  File flightData = SD.open("HAB Flight Data.txt", FILE_WRITE);
  if (flightData) {
    flightData.print("HAB FLight Data");
    flightData.println("Temperature, Pressure, Altitude, Humidity, X-Axis, Y-Axis, Z-Axis");
  } //end if - flightdata
} // end main setup

void loop() {
  //var to hold sensor data
  float BMEt1 = (bme.readTemperature());
  float BMEh1 = (bme.readHumidity());
  float BMEp1 = (bme.readPressure() / 100.0F);
  float BMEa1 = (bme.readAltitude(SEALEVELPRESSURE_HPA));
  // register events for ADXL
  sensors_event_t event;

  // print out BME data to serial monitor
  Serial.println("BME Data.");
  Serial.print("Temperature = "); Serial.print(BMEt1); Serial.println(" *F");
  Serial.print("Pressure = "); Serial.print(BMEp1); Serial.println(" hPa");
  Serial.print("Approx. Altitude = "); Serial.print(BMEa1); Serial.println(" meters");
  Serial.print("Humidity = "); Serial.print(BMEh1); Serial.println(" %");

  // print out ADXL data to serial monitor
  Serial.println("Accelerometer Data");
  Serial.print("X: "); Serial.print(event.acceleration.x); Serial.print("  ");
  Serial.print("Y: "); Serial.print(event.acceleration.y); Serial.print("  ");
  Serial.print("Z: "); Serial.print(event.acceleration.z); Serial.print("  ");

  delay(1000); //Pause between readings.

  // Create a txt file adn record data
  File flightData = SD.open("HAB Flight Data.txt", FILE_WRITE);
  if (flightData) {
    flightData.print(BMEt1); flightData.print(","); flightData.print(BMEp1); flightData.print(",");
    flightData.print(BMEa1); flightData.print(","); flightData.print(BMEh1); flightData.print(",");
    flightData.println("X: "); flightData.print(event.acceleration.x); flightData.print(",");
    flightData.println("Y: "); flightData.print(event.acceleration.y); flightData.print(",");
    flightData.println("Z: "); flightData.print(event.acceleration.z); flightData.print(",");
  } //  end if - data recorder
  else {
    Serial.println("error opening HAB Flight Data.txt");
  } // end else - SD error

} //end Main loop
  • 2
    reduce your code to only create a file on the SD card and write some fixed data to it (like "abc123") ..... do not include anything else in your code .... run a test and update your question with the result .... also update your program listing so that it shows the minimized code – jsotola Nov 29 '18 at 22:59
  • 1
    I took the sensors and code apart and tested individually before slowly incorporating things back together. Thank you for the advice, it was what I needed! – ChaoSweeper Nov 30 '18 at 21:10

[SOLVED] - Based on the advice of a few different people I slowly took the code apart and tested each part individually before plugging sections back in. I also tested the code on new sensors individually after seeing it working, I made a new wiring harness and retested. Worked perfectly!

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