I recently bought a Qwiic Pro Micro and had trouble getting the device to program and the ports to stay open, which seems like a pretty common issue. I’m on an Arch Linux machine, which adds an extra wrinkle. I managed to get the device working, so I’m writing this down should anyone else experience the same issues.
Symptoms: Able to program the board in bootloader mode (double click reset), however no serial communication. ACM port appears briefly and then drops out. Device does not show up in lsusb.
Solution:
- For whatever reason, installing the arduino-IDE via pacman has various errors and glitches. This is solved by downloading a nightly build, extracting, and running direct from the folder. I do not need to run as sudo.
- Follow the wiki steps for udev rules.
- Install the board per the sparkfun instructions.
- Plug in the board and check lsusb. Mine shows up as “SparkFun Pro Micro”. It may not show up at first, but should after you complete all steps. Check again when you’re done.
- Make sure your processor is set to 5V, even if you’re running 3.3V by cutting the jumper.
- Get your blinky code ready.
- Double click the reset button to get the longer bootloader and upload your code.
After getting blinky sent over successfully, the ACM port stayed open and I was able to upload future sketches without double clicking reset. Also, make sure you close the serial monitor before you upload new code (including other sketches you may have in the background and forget about like me).