I have a minipc and it has two HDMI outputs.

After a week of frustration, I am unable to get USB to serial working.
I have installed the drivers. I have added legacy hardware to get
Ports (COM & LPT)
but no
is available.

I suspect it has been disabled at the motherbaord level somehow

Is there any other way to connect to an Arduino via USB?
Is there a USB hardware adaptor that can facilitate a USB serial adaptor? (not a D connector)

How do you check this? Installing the drivers alone will not show up any USB-Comport in device manager. You must also connect an appropriate device at an USB port to see this in device manager. If once such a device was connected, you can still see it after unplugging if you mark 'View-> Show hidden devices' in device manager.

I don't think this is possible. At the motherboard level you can only disable USB at all, but not specific USB functionality that is provided by software.

I have another serial device that runs on the STM virtual COM port driver. That device connects fine with the driver installed on a laptop, but will not connect to the Beelink which is running Win10 Pro also.

When I plug in that device, it shows up in the device manager which reports it is unable to confrigure it.

I know how to see hidden devices and install legacy drivers. Tried every combination you can think of.

I have tried everything to get UNIVERSAL SERIAL ADAPTOR to show up in Ports (COM & LPT). it just wont install.

I agree with you that it this is a software driver for USB port hardware and thus should be available. I have been working on this for over a week. Read many sites. Run many driver updater programs. This is not a common problem which leads me to guess it is a motherboard issue that windows is seeing

Look at the complete name of the driver on the laptop. Can you find it on the Win10PC? What OS is the laptop running?

Yes! the drive is version 1.3. It installed fine on the laptop and installed ok on the beelinkl Windows reports is is ready to use. But there is no Universal serial bus (COMxxx) adaptor in the Ports of device manager so it cant be used.

This is the THE PROBLEM i believe )

It is why none of the Arduion drivers will work also.

I am unable to install the universal serial bus adaptor to ports and I am not clear why.

I suspect that this miniPC does not have a chip that a serial adaptor can recognize

PL-2303 CheckChipVersion Tool Program v1.0.2.0
For Windows OS Only

System Requirement:
. USB 1.1/2.0/3.0 Host Controller
. Device using PL2303HX/X/EA/RA/SA/TA/TB version chips
. Device using PL2303GC/GS/GB/GT/GL/GE, PL2323 version chips
. PL-2303 Windows Driver Installer v1.8.0 or above
. Supports the following Windows OS Family:
- Windows 7 (32 & 64 bit)
- Windows 8/8.1 (32 & 64 bit)
- Windows 10 (32 & 64 bit)
- Windows 8 is NOT supported in HXA/XA chip versions (will show yellow mark Error Code 10).
- Windows 8 is supported only in following chip versions:
- PL2303HXD (HX Rev D)
- PL2303EA (ESD protection)
- PL2303RA (Built-in transceiver)
- PL2303SA (SOP8 package)
- PL2303TA (PL2303HXA/XA replacement)
- PL2303TB (12 GPIO)
- PL2303GC (PL2303HXD replacement)
- PL2303GB
- PL2303GT (Built-in transceiver)
- PL2303GE (ESD protection)
- PL2303GS

Supported device ID and product strings:
. VID_067B&PID_2303 for "Prolific USB-to-Serial Comm Port"
. VID_067B&PID_2304 for "Prolific USB-to-Serial Comm Port" (PL2303TB chip)
. VID_067B&PID_23A3 for "Prolific PL2303GC USB Serial COM Port"
. VID_067B&PID_23B3 for "Prolific PL2303GB USB Serial COM Port"
. VID_067B&PID_23C3 for "Prolific PL2303GT USB Serial COM Port"
. VID_067B&PID_23D3 for "Prolific PL2303GL USB Serial COM Port"
. VID_067B&PID_23E3 for "Prolific PL2303GE USB Serial COM Port"
. VID_067B&PID_23F3 for "Prolific PL2303GS USB Serial COM Por"
. VID_067B&PID_23GD for "Prolific PL2320 USB CDC Serial Port"
. Other VID/PID based on PL2303 chip.

How to Run Tool Program

  1. Install PL-2303 Windows Driver Installer v1.8.0 or above.
  2. Plug PL2303 USB Device and go to Device Manager to check COM Port number.
  3. Run PL2303CheckChipVersion tool and set COM Port number.
  4. Click Check button to show PL-2303 chip version.

NOTE: This program cannot detect HXA/XA chip in Windows 8 and above.

Download Latest Driver here:

Prolific Technology Inc.

Nothing is recognized by this tool


This program can only recognise devices with a prolific chip. Is there anything connected to your PC with such a chip?
As far as I know Due and STM don't use such chips.

It's the other way round: Your serial adaptor will not recognise any chip on your PC, but your PC must regognise the chip on the serial adaptor. This usually is done by a suitable driver which is written for the serial adaptor.

OK this is where we have to be very careful with nomeclature :slight_smile:

I do not have a harware serial adaptor. A thing with a wire and female D9 on one end, and a USB male plu on the other. No no no.

I have a minipc with 4 usb ports. 2x2.0, 2x3.0
To connect to an Arduio via a serial connection using a wire from the Arduion with a USB male plug on it, I need windows to perform the interface via a software adaptor called UNIVERSAL SERIAL BUS (COMXXX) that resides in the ports section of device manager. THIS IS NOT PRESENT and I cant get it to install

Now I am trying to install 3rd party adaptors in the hoipe something might work or someone might know what in the sam hell is the problem!

At the end this IS a hardware serial to USB adapter. Depending on the type of board it is really a hardware serial-USB adapter included on the Board, or the processor chip itself includes the USB HW , and at the USB line it behaves like such an adapter. So there is no difference if you have a separate USB-serial adapter or an Arduino Board.
In either case you need a software driver suitable to your specific Arduino board that is able to communicate with your board. The prolific driver and tool will not help.
And a comport in device manager will only show up, if the Arduino-board is connected.