By default Tuner Studio connectivity is using pin PC10 for TX and PC11 RX, baud rate 38400. Do not forget about GND wire.
Please be sure to use current firmware version with current rusefi.ini project from build_server
Troubleshooting Tuner Studio connectivity
First of all make sure that you have serial port drivers installed. STMicroelectronics Virtual for microUSB or USB serial for PC10/PC11
You can test physical connectivity with a terminal application like putty: 1) connect to the TS port 2) type 't' you are expected to see a response like this:
Q: I try to connect with Tuner Studio and it says "line:532:rusEfiVersion,20140822@4388 Ford Aspire,outpin,c1@PC6,outpin,c2@PA5,ou"?
A: what you have is a piece of rusEfi own console text-based protocol, you need to connect TS to the other port.
Q: how should it look in Tuner Studio mini terminal?
A: like that. Note that now new lines between 't' symbols, note that at first some random stuff was received once and that's OK