USB Port on TFT 35 with SKR Pro 1.2

Bene searching the forums and I am fairly new on CNC and I have an SKR Pro 1.2 and TFT35, bought from V1engineering and pre-flashed for an LR3. Everything works on the TFT like homing and manual moves and I would like to be able to use the USB port on the TFT to connect to a PC for manual testing with Repetier-Host over having to create gcode and use the card port. Do I have to reflash my SKR Pro board to to get the USB on the TFT35 to work with a laptop? If so are there instructions on that process and is there anything needed to be done to the TFT35?

Thank you



Connect the USB from the SKR Pro board to your computer, make sure the baud rate is set to 250,000 and the port is correct in repetier host (make sure you are not using repetier server).

There really is no need to connect a computer directly, everything can be done from the screen.

You do not use the USB Port on the connect to a PC.

The USB B port on the mainboard is used to connect to a PC.

The USB port on the TFT is used to hold gcode files that you can access from the touch screen “Print” menu. You can also.use the SD card slot in that way. The SD card slot is also available in “Marlin Mode” on the TFT, but the USB port is not.

If touch screen mode is working on the TFT, then all functions are already available. The TFT acts like a limited computer. It can talk to the SKR Pro, but doesn’t really want to your desktop, and most definitely.not over USB.

1 Like

Ummmm… from the addendum on

Printing from Host

OctoPrint, ESP3D, Pronterface etc, connected to a TFT’s serial port, can browse files on both the TFT’s and mainboard’s media devices and start a print that will be handled by the host (TFT or mainboard). The following actions and the related triggering G-codes are currently supported by the TFT fw:


Printing from Remote Host

OctoPrint, ESP3D, Pronterface etc, connected to a TFT’s or mainboard’s serial port, can host a print (print handled by the host) and optionally can trigger some actions to the TFT sending specific G-codes. The following actions and the related triggering G-codes are currently supported by the TFT fw:

It doesn’t specify which serial port it is talking about but I can’t see how it could be talking about the TFT to skr serial connection…

That being the case, there should be no configuration changes needed Glenn, just plug it in and away you go. People generally use the main board USB to connect to the computer though!

We don’t have that enabled, that is why we use the SKR USB port. The TFT is a bit wonky so the less it does the better. As it is, the firmware was just fixed enough to printer faster with it. We have never had any CNC issue because we have it configured minimally but these screens have had a major bug for years in terms of printing.

1 Like

Right. The serial port which is not the USB port.

The ESP01S port (8 pin female pin header) of those serial ports and can be used to browse files. Before Ryan set up the ESP01S as connected directly to the SKR Pro, I connected it to the TFT, which required a small remix of the TFT case

There is another serial UART on board the TFT as well, but it is not connected to USB. I have never used it and have no intention to. You could use a USB to serial device similar to what you use to program the ESP01S.

You could enable it with a change to the config.ini file, (like I did for the wifi port) but it will not just conveniently work through Repetier Host or Pronterface, since those expect to talk to the printer’s firmware and not the TFT firmware. (You will be able to use the serial console, but Im reasonably sure that the command set is different. I could be wrong, but it’s an extra step and without offering that.much (to me) advantage, the USB connection to rhe mainboard is significantly easier.

Thanks Ryan and Dan for the explanation, I did say I wasn’t sure to which serial port the github page was referring.

Thank you all for your replies, I will try it out this weekend and finalize the build.