VEML6075 with expLoRaBLE

Sensors Environmental
1

Hi there,

I’ve been tinkering with the new expLoRaBLE board (which is great) and have happily hooked it up to my TTN account. All good so far.

But on hooking up the VEML6075 via Qwiic and following the tutorial, I’m hit with an error while compiling. I’m able to add in the setup script fine, but the issue seems to come when adding the “Stream UV” example code.

I know the expLoRaBLE board is pretty, new, but any assistance would be hugely appreciated! I’m hoping to set the device up as a sensor hub in the garden.

c:/users/charcal/appdata/local/arduino15/packages/sparkfun/tools/arm-none-eabi-gcc/8-2018-q4-major/bin/../lib/gcc/arm-none-eabi/8.2.1/../../../../arm-none-eabi/bin/ld.exe: C:\Users\CharCal\AppData\Local\Temp\arduino_cache_62770\core\core_7648347cdbfe68e40944e0f46369a71a.a(String.cpp.o): in function `arduino::String::String(float, unsigned char)':

C:\Users\CharCal\AppData\Local\Arduino15\packages\SparkFun\hardware\apollo3\2.0.5/cores/arduino/mbed-bridge/core-api/api/String.cpp:116: undefined reference to `dtostrf'

collect2.exe: error: ld returned 1 exit status
exit status 1
Error compiling for board LoRa Thing Plus expLoRaBLE.
2

Just to update, I borrowed some code from the Adafruit VEML6075 example sketch and now have readings in the serial window.

  Serial.print("uva:  "); Serial.println(uv.uva());
  Serial.print("uvb:  "); Serial.println(uv.uvb());
  Serial.print("uv index: "); Serial.println(uv.index());

Now for a second question (sorry, still quite new to Arduino IDE) - is there any documentation to get sensor data from the ExpLoRaBLE to TTN? I can get “Hello World”, but would like to transmit and decode sensor readings. Google hasn’t been helpful so far!

Here is the code from the example sketch for the board:

  uint8_t mydata[] = ("Hello World");
  LMIC_setTxData2(1, mydata, sizeof(mydata) - 1, 0);

Any help appreciated!