SARA-R510AWS - ESP32 not working

Development Boards MicroMod
1

I am writing to inform you that we recently purchased the SARA-R510AWS Micromod board, and we are currently in the process of testing it with Arduino examples.

However, we have encountered an issue with the Arduino examples that involve interfacing with the u-blox component. Unfortunately, these examples do not seem to be functioning as expected. Despite our efforts, we have been unable to achieve the desired results.

I am currently using is: https://www.sparkfun.com/products/21229 , which appears to differ from the one referenced in the tutorials on your website https://www.sparkfun.com/products/17272 and associated Arduino library and examples https://github.com/sparkfun/MicroMod_Asset_Tracker .

After reviewing the documentation for SARA-R510AWS, I found that the TX and RX pins on the board are labeled as 12 and 13, respectively. These are then mapped to your board’s pins 17 (also referred to as G3 or TX1) and 19 (also known as G4 or RX1), which are further remapped to the ESP32 (provided in the kit) on GPIO 17 and 16.

Here’s a summary of my attempts:

  1. Connected via the module https://www.sparkfun.com/products/17725 , configured the board through USB UART, and successfully sent a message to my AWS MQTT broker.

  2. Installed MicroPython on the MicroMod ESP32 module without any issues.

  3. Powered up the ublox module using MicroPython, and it worked fine (LED lit up).

  4. Configured UART using the library, issued the “AT” command, but did not receive “OK” (configured with pins 16 and 17).

  5. Attempted to use the I2S library to check if the issue was with the microphone, but no audio data was received from the buffer.

  6. Tried Arduino examples provided by SparkFun, and all non-SARA-R510AWS sensor-related examples worked (e.g., blink, imu), while those requiring the ublox module did not (12>).

  7. Tested with the micromod stm32 module https://www.sparkfun.com/products/21326 , but observed no difference.

Thank you very much for your help.

2

Are you using the instructions here? https://github.com/aws/iot-expresslink (note that the board/AWS uses a modified AT command set)

Since the other examples are working (it might help to be sure to test those same pin #s), I’m leaning toward suspecting an AWS setting or similar on-boarding being an issue

3

Thank you TS-Russell for your response. The issue actually lies before the “type of AT command.” With the “AT” command to which SARA should respond with “OK,” there is no response at all. Therefore, the problem is with the pins on the SparkFun board, which are definitely not correct. Do you have the same board, and were you able to make it work?