Select the correct COM port for your rusEFI. You will usually see only two COM ports. Chances are, the one with the higher number is the rusEFI COM-port. For most cases, the selected Baud rate does not matter.
If you can't establish communication, try baud rate 38,400 | 57,600 or 115,200. If that doesn't work, you may need to try a different COM port.
After selecting the COM-port (and baud rate), click on "Test Port". This should result in a "successful!" message. If you get a failed message, you need to adjust your settings. After a successful test of the port click "Accept".
**Question:** found [here](http://rusefi.com/forum/viewtopic.php?f=5&t=210&start=29)
I'd like to try to connect to Tuner Studio and see what happens. I have a USB/TTL device which looks the same as the photo that Andrey posted. What do I connect to what and what is the procedure?
1. Verify pin assignments for your USB TTL cable. Colors might be slightly different from what is shown above and there maybe additional wires which are not needed. Before connecting the TTL to the brain board, connect it to your desktop and install the drivers if required.
2. Once the USB TTL Serial device and drivers are installed, connect GND wire to GND on the brain board
This UART/real serial is just another way to connect either TunerStudio or rusEFI console to the firmware. By combining both microUsb virtual serial and TTL real serial one can connect to rusEFI with both TunerStudio and rusEFI console simultaneously.