Klangstrom is a project in a very experimental state. there are a number of known issues. in addition to the following list, make sure to also consult the issues tracking system where bugs + feature requests are submitted.


  • Desktop Emulator currently only works on macOS and partly on Linux
  • Desktop Emulator lacks most Arduino functions



  • SD Card reader is not working. CS is not connected properly.
  • HEADPHONE+MIC ( TRRS audio jack ) requires adapter OMTP to CTIA/AHJ
  • SERIAL_00 + SERIAL_01 require dedicated twisted cable
  • GPIO_07 is also used by the programmer button


  • 5/12V power switch does not work. jumper PATCH_5V needs to used to power the board.
  • USB connectors ( HOST + DEVICE+PWR ) are switched. in Arduino IDE this can be rectified by selecting High Speed in Full Speed mode ti use DEVICE+PWR connector and Low/Full Speed to use HOST. however, for DFU upload to work a custom USB-A-to-USB-A cable must be used on HOST connector.