All firmware burnt to my Dan Dock M1 results in garbage output at the USB serial terminal. Take the hello_world example, the output looks like
$ python -m serial.tools.miniterm --- Available ports: --- 1: /dev/cu.Bluetooth-Incoming-Port 'n/a' --- 2: /dev/cu.YuchisBeatsSolo3-SPPSer 'n/a' --- 3: /dev/cu.YuchisBeatsSolo3-Wirele 'n/a' --- 4: /dev/cu.usbserial-1430 'USB2.0-Serial' --- 5: /dev/cu.wchusbserial1430 'USB2.0-Serial' --- Enter port index or full name: 5 --- Miniterm on /dev/cu.wchusbserial1430 9600,8,N,1 --- --- Quit: Ctrl+] | Menu: Ctrl+T | Help: Ctrl+T followed by Ctrl+H --- (␀
Note that each time I reset the board by pressing that button, the output would change, but its length remain fixed. I have overclocked it to 600MHz in a previous experiment, and I wonder if that has somehow damaged the board?