Technical issues

Linux

Permission denied

When trying to upload code to the Wemos D1 mini, you might get permisson errors like:

• avrdude: ser_open(): can't open device "<port>": Permission denied
• avrdude: usbdev_open(): can't open device: Permission denied
• No device found on <port> (bossac)
• dfu-util: No DFU-capable USB device available

This is solved by running the following command in the terminal:

sudo usermod -a -G dialout $USER

After running this command, the user needs to log out and log back in for the changes to take effect. You can check if the user is in the dialout group by running the following command:

groups

Ubuntu

Ubuntu 22.04 issue with recognising any MCU boards, this is solved by running the 4 following commands in the terminal:

systemctl stop brltty-udev.service
sudo systemctl mask brltty-udev.service
systemctl stop brltty.service
systemctl disable brltty.service

Windows

General

Program stops working after a certain amount of time, this is usually a memory leak, which is solved by either declaring all variables globally or by solving the leak or by malloc and free commands (does not work in every case). For more information on this, see General information.

Wemos motor shield not working with 2 motors, no fun solution sadly, the solution used due to time limits was adding more motor shields and if necessary a multiplexer.

Wemos motor shield v1 not working correctly. solution: do not use v1 until an SA flashed these.