Inspiron

Last reply by 02-03-2021 Unsolved
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2 Bronze
2 Bronze
2518

Inspiron 5770 Windows 10 - How to make USB look like COM port?

I have a legacy device that connects via USB, but needs to look like a COM port. In Device Manager, Ports (COM and LPT) does not even appear as it did in previous versions of Windows. So, how do I make my USB ports recognize a serial interface over USB? Do I need a new driver? If so, which one and where do I get it?

Replies (9)
6 Indium
2491


@mencik wrote:

I have a legacy device that connects via USB, but needs to look like a COM port. In Device Manager, Ports (COM and LPT) does not even appear as it did in previous versions of Windows. So, how do I make my USB ports recognize a serial interface over USB? Do I need a new driver? If so, which one and where do I get it?


The driver you need depends on the IC that is in the adapter you are using which we don't know anything about except that you have one. 

 

 

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2465

It is a simple USB cable, no adapter. On other computers, like my older HP also running Windows 10 and others running older versions of Windows, there is a section in the device manager for Ports (COM and LPT). On the Inspiron, there is no such section. If that section was there, you can select which COM port a USB device represents. Obviously something is different with the Inspiron as far as how the USB acts, and I suspect a driver is missing. If it is something else, I am open to suggestions.

 

2460


@mencik wrote:

It is a simple USB cable, no adapter. 

 


That makes no sense!

 

2447

You obviously have never dealt with a device that uses the old USB Type B to USB Type A cable for older devices. It communicates with the system as if it were a COM serial port. On many computers you can look in device manager and see Ports (COM & LPT) and you can specify the particular port that a USB interface will look like. On the Inspiron 5770 with latest Windows 10, the Ports (COM & LPT) is not part of device manager, so I can't specify, and my device cannot connect. It does not auto-detect.

2441


@mencik wrote:

You obviously have never dealt with a device that uses the old USB Type B to USB Type A cable for older devices. It communicates with the system as if it were a COM serial port. On many computers you can look in device manager and see Ports (COM & LPT) and you can specify the particular port that a USB interface will look like. On the Inspiron 5770 with latest Windows 10, the Ports (COM & LPT) is not part of device manager, so I can't specify, and my device cannot connect. It does not auto-detect.


ROTFL.

I haven't have I????

ROTFL.

 

I guess you would have to tell my current employer that I am not actually programming for the COM port!

It is all in my imagination.

 

Your device needs a Windows 10 driver.

.

2437

Welcome to the Dell Community  @mencik 

Power-on and start tapping "f2" to enter BIOS setup.

See if you have the option to Enable or Disable the Serial Ports.

Best regards,

U2

7 Plutonium
2425

It depends what USB to Serial Adaptor you have. These ones Plugable USB to RS-232 DB9 Serial Adapter (Prolific PL2303HX Rev D Chipset) have a Driver which Windows 10 obtains directly from Windows Update. Do you have any unknown Devices or any Devices marked with an ! or ? in the Device Manager? If not does the port work on another PC?

 
 

Dr Philip Yip
Tech Enthusiast and Author of the Unofficial Dell Windows Reinstallation Guide

Windows FAQs and OEM Downloads


#IDoNotWorkFor Dell
10 Diamond
2416

https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/usb-driver-installation-based-on-co...

The PL-2303HX is a low cost and high performance USB-to-Serial Bridge Controller. Prolific does not make adapters.

The PL2303 Windows 10 driver can also be downloaded automatically via Windows Update. Just plug-in the PL2303 USB Serial device and Windows Update (Internet connection is required) will download and install the latest drivers.

NOTE:

  • Windows 10 is NOT supported in PL-2303HXA/XA EOL (End-of-Life) chip versions.
  • Prolific recommends to buy PL-2303HXD (HX Rev D) chip or newer generation chip versions.

Because this works the chip is often counterfieted. So beware of FAKE PL2403HXD adapters.

https://www.amazon.com/Plugable-Adapter-Prolific-PL2303HX-Chipset/dp/B00425S1H8

Windows Driver Installer Setup Program 
(For PL2303 GC, GS, GT, GL, GE & PL2323 versions)

http://www.prolific.com.tw/US/ShowProduct.aspx?p_id=225&pcid=41

USB SERIALUSB SERIAL

 

Windows 10

In Windows 10, a new INF, Usbser.inf, has been added to %Systemroot%\Inf that loads Usbser.sys as the function device object (FDO) in the device stack. If your device belongs to the Communications and CDC Control device class, Usbser.sys is loaded automatically.You do not need to write your own INF to reference the driver. The driver is loaded based on a compatible ID match similar to other USB device class drivers included in Windows.

USB\Class_02

USB\Class_02&SubClass_02

Starting in Windows 10, Usbser.sys supports USB Selective Suspend. It allows the attached USB-to-serial device to enter a low power state when not in use, while the system remains in the S0 state. When communication with the device resumes, the device can leave the Suspend state and resume Working state. The feature is disabled by default and can be enabled and configured by setting the IdleUsbSelectiveSuspendPolicy entry under this registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\USB\<hardware id>\<instance id>\Device Parameters

To configure power management features of Usbser.sys, you can set IdleUsbSelectiveSuspendPolicy to:

  • "0x00000001"

    Enters selective suspend when idle, that is, when there are no active data transfers to or from the device.

  • "0x00000000"

    Enters selective suspend only when there are no open handles to the device.

 

 


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@nyc10036 Why are you being so mean? The fact that you know more than someone about a subject does not mean you have to be rude to them about it.

 

@mencik good luck friend, sorry I can't help you out here

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