8-Port Industrial USB 2.0 to RS-232 DB-9 Adapter High-Speed FTDI Chip

RS-232 | 512 Bytes Receive | 512 Bytes Transmit

  • Superior Build Quality: Housed in a rugged steel chassis with optional mountable flanges, the serial adapter hub is perfect for installations in labs, warehouses, or heavy machinery.
  • Industrial Connections: Designed for use with Bar Code Scanners, Time Clocks, Label Printers, Point of Sale Terminals, Receipt Printers, and more
  • Expand Your Serial Capabilities: Connect 8 legacy 9-pin serial device through a USB-A port to add legacy functionality to newer technologies with no serial port connections.
  • COM Retention: COM Ports are fully configurable, and after reboots, port assignments are preserved.
  • USB Power: Power is drawn from a USB connection, no bulky power supply or power outlet is required. 
  • Upstream: 1 USB port, Type B Female Connector
  • Downstream: 8 Male DB9s, w/ nuts


(1 customer review)

In stock

Volume Pricing

Units Price
1 - 4 $249.95
5 - 11 $242.45
12 - 24 $237.45
25 - 49 $232.45
50+ $224.96

Also available from:

Model No. USBG-8COM-M



The USBG-8COM-M Industrial 8-Port DB-9 RS232 to USB Adapter provides scalability to quickly adapt to new USB technologies to drive your system expansion. Multiple modules can be added to a single USB interface allowing you to add RS232 connectivity as needed. This device is supported by Windows 11.


With its USB Plug-and-Play feature, follow the instructions of Install Wizard once connected to your host port and complete the install. You don’t have to deal with Card Slots, I/O address, IRQ jumpers, DMA and others when you are connecting the devices, the system will recognize the device and install the drivers automatically.


  • Data Rate from 75 bps to 921.6Kbps
  • 512-Byte Deep FIFOs for each Port
  • Rigid Metal Case for Critical Applications
  • Provides 8 RS232 Serial Ports over USB Port
  • Provides 8 DSUB-9 Connectors
  • Supports 5,6,7,8 Data Bits
  • Odd, Even, Mark, Space, or None parity mode
  • Supports 1, 1.5 and 2 Stop Bits
  • Supports USB Bus Power

OS Support:

  • Windows 98, Me, XP, 2000, 2003, CE, Vista, Windows 7, 8, and 10
  • Linux and Mac OS

Power Requirements:

  • Normally Power solely from USB Bus, no external power supply needed.
  • 5V DC Jack Input for supports Power over DB9-Male applications.

Form Factor:

  • 6.83(L) x 3.83(W) x 1.70(H) (17.35 x 9.72 x 4.32 cm)

Package Contents:

  • 8 port USB to Serial adapter
  • Power supply and power cord
  • USB A to B cable
  • Paper installation manual

Product Specifications

Input Voltage

+5V DC

Power Source

DC Barrel Jack 1.3mm ID × 3.5mm OD

External Power Required


Country of Origin






Item Dimensions (L × W × H)

6.83 × 3.83 × 1.70 in.

Item Weight

1.193 lbs.

Mounting Style

Surface Mount


8 Serial Ports

Material of Construction


USB Type

USB 2.0

Upstream USB Ports

1 Type-B Female USB

Screw Lock Compatible


Serial Attributes
Serial Standards


Baud Rate

921.6K bps

FIFO Receive

512 bytes

FIFO Transmit

512 bytes

Data Bits

5, 6, 7, 8


None, Even, Odd, Mark, Space

Stop Bits

1, 1.5, 2

Flow Control

Hardware (RTS, CTS), XON/XOFF

OS Support

Linux, Mac OSX, Win 10, Win 7, Win 8, Win XP

Product Information

1 year from date of purchase

Other Data

DB9 Male w/ Nuts


1 year from date of purchase


2 lbs


11.5 × 7.5 × 2.75 in

UPC: 729440626983

DB9 RS-232 Pin-Outs

DB9 RS-232 Pin-Out Diagram
DB9 RS-232 Pin-Out Chart
Accessories & Replacement Parts

Accessories & Replacement Parts

The Industrial 8-Port DB-9 RS232 to USB Adapter has certain accessories that work with it. These accessories are what you can order if needed.

USB 2.0 Cable for close connections Use this USB 2.0 cable to connect your desktop or laptop using a USB hub, printer, or scanner. Transfer…

Model# USB2-AB


In stock

6in 16in 1ft 2ft 3ft 4ft 5ft 6ft 10ft 15ft
This option is required
Black White
This option is required

Select options

RS232 Male to Female Serial Data Cable Complete your serial data connection with this 5ft. RS232 DB-9 Male to Female data cable for fast reliable…

Model# 9DBMF5FT


In stock

Add to cart

Serial F.A.Q.

Product F.A.Q.

View frequently asked product questions below. For all serial troubleshooting, visit this page.
Still need help? Reach out!

  • How do I clean and reinstall my FTDI drivers?
      1. Download the CDM Uninstaller HERE.
      2. Extract the zip file, or open the “CDMuninstallerGUI.exe” utility.
      3. Leave the ‘Vendor ID’ set to 0403 and ‘Product ID’ set to 6001.
      4. Click Add.
      5. Click Remove Devices.
      6. Download the corresponding driver for your operating system and follow on-screen prompts. Windows Driver | MacOS Driver

    Video tutorial here.

  • How can I change my device’s COM port?
      1. Click on Start and navigate to the Control Panel
      2. Locate and click on Device Manager
      3. Under “Ports (COM & LPT)” you will find your serial device titled “USB Serial Port” along with its current COM Port.
      4. Right click on “USB Serial Port” and click on Properties.
      5. Navigate to the “Port Settings” tab and click on “Advanced…”
      6. Once there, the “COM Port Number:” can be changed with a dropdown menu to select the port number.
      7. Click your desired port number (i.e. COM2) and click “OK”.
      8. Click “OK” once more.
      9. Your serial device is now assigned to your chosen COM Port.


  • How do I check to ensure the COM port is listed properly in Windows?
    To ensure your serial device is installed properly, complete the following:

    1. Press Windows Key + R to open the Device Manager. Once Run comes up, type “devmgmt.msc” into the text field and press Enter.
    2. Expand the section labeled, Ports (COM & LPT).
    3. You should now see a COM number in brackets to the right of each port. If the device is installed properly, no exclamation points or question marks should be present next to the device.
  • I have everything hooked up, but nothing is functioning correctly.
    To rule out potential issues, quickly test your individual components to ensure that they are working correctly individually, and are not the source of the problem:

    • Serial cables
    • Serial ports
    • Serial devices

    Test your components by:

    • Hook up the serial cable(s), serial port(s), and serial device(s) in a different setup to see if the issue stems from a particular component, or the setup as a whole.
    • Replace the serial cable, port, or device within your setup to further troubleshoot the issue’s origin.

    When testing cables:

    • Test each cable individually.
    • Use short cables when you are testing.

    When testing serial ports and devices:

    • Press the Windows key + R, in Run, type devmgmt.msc, and press Enter to open the Device Manager. You can then check to see if your device is listed under Ports (COM & LPT).
    • Ensure that the COM port number is the correct number for the serial device and that the software being used to connect the computer to the serial device uses the correct COM port number.
    • If the device is listed with an error, follow the instructions on the website to reinstall the drivers.
  • Serial communication is not functioning correctly, how can I tell if the problem caused by the adapter or my serial software application?
    Older serial communication applications make use of legacy hardware addresses, often incompatible with PCI, PCIe, and USB to Serial products. Contact the software provider to troubleshoot.
  • I am receiving an error when I try to install the drivers in Windows 8 64 bit.
    Driver Signature Enforcement in Windows 8 may need to be disabled in order to use various drivers. After disabling this feature, the driver will be allowed to install.

    Note: You are required to restart your computer after disabling the Driver Signature Enforcement. Save all open work on your computer.

    Disable driver signature enforcement:

    1. Press the Windows key + C.
    2. Click Settings > Change PC Settings.
    3. In the left pane, click General.
    4. In the right pane, under Advanced startup, click Restart now.

    When your system restarts:

    1. Click Troubleshoot > Advanced options > Startup Settings > Restart.
    2. Press 7.

    When your computer restarts, Driver Signature Enforcement will be disabled and you can install the drivers.

  • I am receiving an error when I try to install the drivers in Windows 10 64 bit.
    Driver Signature Enforcement in Windows 10 may need to be disabled in order to use various drivers. After disabling this feature, the driver will be allowed to install.

    Note: You are required to restart your computer after disabling the Driver Signature Enforcement. Save all open work on your computer.

    Disable Driver Signature Enforcement:

    1. Click the Windows icon in the taskbar.
    2. Click Power.
    3. Press and hold the Shift key and click Restart.

    After your computer restarts:

    1. Click Troubleshoot Advanced Options Startup Settings Restart.
    2. Press 7.

    When your computer restarts, Driver Signature Enforcement will be disabled and you can install the drivers.

  • Why did the software not install properly in macOS High Sierra (10.13) or later?
    High Sierra 10.13 and later versions of macOS enforce strict security policy revisions. In order for the device to operate, software packages like those used in this installation must be allowed in macOS Security and Privacy settings once the software is installed.

    Once the driver/software is installed, follow these steps to allow the software:

    1. Open System Preferences.
    2. Open Security & Privacy.
    3. Click the Allow button near the bottom of the General tab.
Reviews (1)

1 review for 8-Port Industrial USB 2.0 to RS-232 DB-9 Adapter High-Speed FTDI Chip

  1. Chris M

    This unit works with Windows XP through Windows 7, I have not tested it with Windows 8, Linux and MacOS X. I have two of these in production and use them to manage several network devices made by Cisco, Netgear and D-Link. I have not had any issues with these devices. If I could make one complaint, it is that the ports are a bit close together. I use the Cables to Go Serial270 DB9 F/F cables which have fairly wide and thick housing around the DB9 connectors, so it’s a little tight, but not so tight that it’s infuriating.

    I love these and plan to buy at least one more soon.

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