Back to what a few others were saying about the compilation problem – I had the same issue, failed to compile a sketch based on the DRWI logging examples, got the error message tied to “AlphasenseCO2.cpp” because of the line “#include <Adafruit_ADS1X15.h>”. I noticed that the Adafruit_ADS1X15 folder in the .zip file that came with the very convenient bundle of libraries described in the EnviroDIY/libraries readme on github includes the file “Adafruit_ADS1015.h”, not “Adafuit_ADS1X15.h”. I removed the Adafruit_ADS1X15 library folder and installed the version of that library available through the Manage Libraries tool in the Arduino IDE. That version includes “Adafruit_ADS1X15.h”. With this replacement, the sketch compiled fine and the board talks to the sensors and logs to the SD card as expected. I am not using any Alphasense CO2 sensors, and I did not dig deeper into possible differences between the two files, so I can’t say whether this will break anything else, but it’s worked so far.
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