USB Serial – USB 2.0 RS232 Adapter with LED Indicators

(16 customer reviews)


This USB to Serial adapter is a tool of choice when supporting serial peripherals in newer computers without serial support. Now supported by Windows 11, this is an ideal solution for device support.


  • Easily connect to legacy USB-A ports
  • Plug and play function
  • Fully supports RS-232 signals
  • LED activity monitoring
  • Supports Windows 7, 8, 10, and 11, Linux, OSX

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Model #: GM-FTDI2-LED Categories: , , , Tag:

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This USB serial device is a USB 2.0 to RS-232 serial adapter used to easily add a serial port to your computer even if they are unequipped with COM port ability. The GM-FTDI2-LED supports peripherals requiring a serial RS-232 connection. This USB serial adapter allows you to add  a single serial port and monitor the status of your connections by using LED activity flashes.

USB to Serial RS-232 Adapter with Type-A connector

When connection activity is present, the LED’s will flash letting you know you have signal on the pins. The GM-FTDI2-LED offers an advanced an FTDI Chipset supported by Windows 11. The device is powered individually by the USB 2.0 port and is easy to install with Plug & Play and easily tests RS-232 Host to Device link with backward compatibility with USB Spec 1.1.

Package Contents:

  • USB 2.0 RS232 Serial Adapter with LED’s
  • Latest FTDI Driver (available for download)
  • GM-FTDI2-LED Product Manual (available for download)


GM-FTDI2-LED full view with ferrite ring and USB connectorDevice Support:

  • PDA RS-232 Port support 56K Modem support Serial Mouse support+ Serial PC camera support
  • Fully compliant with USB Spec 2.0 Compliant USB Spec1.1
  • RS-232 – DB9 / M Data rate : Over 1000kbps
  • ESD Protection for RS-232 I/O’ +-15KV RS-232 for DTE Mode

We’ve written a blog post on Serial Driver Support including information on Windows Operating System life cycle.

DB-9 Pin Assignment
Pin Data Type Input/Output LED Color
1 IN Data Carrier Detect (DCD) Green
2 IN Receive Data Receive (RXD) None
3 OUT Transmit Data (TXD) Green
4 OUT Data Terminal Ready (DTR) Green
5 GND Ground Wire Red
6 IN Data Set Ready (DSR) None
7 OUT Request Send (RTS) Green
8 IN Clear Send (CTS) None
9 IN Ringing Indicator (RI) None


Additional Features & Specifications:
LED Color:

  • 1~4, 6~9 PIN Signal 0 : Green / Signal 1 : RED GND – RED – POWER PS. DB9-F PIN / 1,2,6,8,9 NO Input LED no light
  • Easy test RS-232 Host to Device link

OS Support:

  • Windows 7, 8, 10, and Windows 11
  • Linux, Mac OS 10.X


Additional information

Weight .156 lbs
Dimensions 8.250 × 5.750 × .750 in




Supported OS

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Cable Length




USB to RS232


1 year from date of purchase.

Tech Note

Download page contains a special note with regard to driver install.

Alt Part No


Drivers & Manuals

16 reviews for USB Serial – USB 2.0 RS232 Adapter with LED Indicators

  1. James D.K.

    5.0 out of 5 stars

    works, like the LEDs as I know what they mean, it will help if there are HW or driver issues
    works, like the LEDs as I know what they mean, it will help if there are HW or driver issues

  2. Steve

    5.0 out of 5 stars

    Use to communicate with fire panel
    I needed this to help program and diagnose a fire alarm panel. I initially wired my connector incorrectly and could not get any communication. Thanks to the lights on this adapter I was able to quickly diagnose my mistake and get my programming done. I had originally used a more expensive adapter from a local store but couldn’t get any communication and thought it was defective (which I later learned was my mistake). If you need a USB to serial, this is the only way to go!

  3. Paul Mills

    4.0 out of 5 stars

    Works, but
    Would be nice if LED’s were two color and showed true state of each line. Don’t buy it for line monitoring capabilities.

  4. Vandy Starkweather

    It works fine
    Easy to setup and use.

  5. PumpkinSeed

    This is the one to get
    Don’t mess around with other chipsets that can be unstable, have poor driver support and even may cause Blue Screen of Death when connecting and disconnecting. This has the very reliable FTDI chipset with status indicator lights at a great price. Cheers! ~Andrew

  6. Kerrick

    great deal
    I have needed this for a while now. I ordered and received easy to use and worked perfect. makes life easier programming 2-way radios.

  7. Arno

    Very helpful when resolving RS232-USB problems
    Too bad they put on the sticker slightly shifted so the indicators were not clear to see. Re-sticking it is a bit of a pain. For the rest a very handy and good working device.

  8. Big John

    Okay. Usable – though not perfect
    It didn’t work for my project but I suppose I can use this cable. I will keep it. I like the data light feature, that’s the best thing about it.In terms of quality— It’s too expensive for the cheap looking design and feel.

  9. dontcrossme

    Worked great on multiple devices so far.
    I have had no issues connecting to, Watchguard, Cisco, Dlink, HP switch with this adapter and the Serial to RJ cable.

  10. Rodney B

    Fast delivery
    Works, but found I didn’t need it right away.

  11. JC

    Works great with Windows 10

  12. Virgil N.

    Not a problem
    Plug it in and it worked

  13. Wulfie

    Rock solid connectivity so far
    The female connector screws refuse to come out, annoying since i cannot use the dongle directly on the equipment ,have to use a male female cable extension.

  14. Roger

    For Linux operating systems, activate the CONFIG_USB_SERIAL_FTDI_SIO config option and rebuild the kernel, or:# cd /usr/src/linux && make menuconfigLinux > Device Drivers > USB > USB Serial Converter > USB FTDI Single Port Serial Driver# make bzImage && make modules && make modules_install && make installShould see something within syslog similar to the following:Product: FT232R USB UARTManufacturer: FTDISerialNumber: XXXXXXXXDetected FT232RLFTDI USB Serial Device converter now attached to ttyUSB0

  15. Aaron Chesney

    Works just fine, would buy again
    It reports to the OS that it is FTDI, who knows anymore. But it works absolutely fine, would buy again.

  16. Mobius

    Works perfectly, no additional drivers needed
    Worked (almost*) right out of the box. Tested only in Windows 10 64 bit.Needed to program a universal remote (URC MX-800, also should work with all other variants like MX-600, MX-700, etc). *The default latency was set to 16ms which made it not communicate with my equipment properly, but setting it to 1ms in device manager solved it.LED’s are nice and useful, you can see which lanes/pins are actively receiving or transmitting.Material of the case is good.Two things that could make this even more perfect in my humble opinion.Make the cable the same color as the case (smoke colored). As it is, it looks like something from 2003 or so with its see-through cable and being able to see the sheilding.Second, if they could somehow add a opaque piece of plastic between each LED so the light doesnt bleed into the holes next to it, it would look so much more nice looking and easier to read the LEDs.

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