When this happens, it means that more than one device is trying to use the same I/O port. Open the device manager and see if there are any yellow exclamation points ...
(LOW start, 8 data bits LSB-first, two HIGH stop bits). DEFAULT_VCD = PROJECT_ROOT / "waveforms" / "toyota_obd1_gpio21.vcd" DEFAULT_GTKW = PROJECT_ROOT / "waveforms" / "toyota_obd1_gpio21.gtkw" # INJ ...