StarTech.com

1 Port FTDI USB to Serial RS232 Adapter Cable with Optical Isolation

Add an RS232 serial port with circuit isolation to your laptop or desktop computer, through USB

Product ID: ICUSB2321FIS

  • USB to Straight-Through RS232 Serial Adapter
  • Integrated 2500Vrms Optical Isolation Circuits
  • 500W Bi-Directional Surge Protection Circuits
View More
  • Integrated FTDI USB UART Chip
  • COM Port assignments maintained across reboot
  • Compatible with Windows®, Mac OS and Linux
  • Baud Rate up to 921.6 Kbps
  • Powered by the USB port - no external power adapter required
  • Designed to make serial port expansion quick and easy
  • 8-foot cable length for connecting to devices without having to be too close
122,99 € EUR exc VAT
151,28 € EUR inc VAT
93+ In stock
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Overview

The ICUSB2321FIS 1-Port FTDI USB to Serial RS232 Adapter Cable with Optical Isolation converts an available USB 1.1 or 2.0 port into an RS232 DB9 port that can be used to connect, monitor and control your serial devices.

The USB to serial adapter features integrated optical isolation circuits and surge protection to protect your critical, sensitive control equipment against electrical damage, making it a viable solution for costly industrial serial devices.

The versatile FTDI chipset also supports COM retention, additional customization/features, and compatibility not offered by most other solutions. Broad operating system compatibility including Windows®, Windows CE, Mac OS and Linux, makes this product easy to integrate into mixed environments.

Backed by a StarTech.com 2-year warranty and free lifetime technical support.

The StarTech.com Advantage

  • Circuit isolation provides electrical protection for sensitive, and often expensive industrial equipment
  • Portable USB-Powered design requires no bulky power adapter or outlet
  • The FTDI chipset driver is highly customizable and broadly compatible, making it the ideal solution for any setup

Applications

Perfect for IT Administrators looking to add legacy functionality to newer laptops, desktop computers and servers that lack an integrated RS232 port

Connect, monitor and control industrial/automotive sensors and other sensitive equipment

Connect bar code scanners, receipt printers and other point-of-sale devices

Connect and program LED and Digital signage boards with serial communication ports

Connect a satellite receiver, serial modem, or PDU

Technical Specifications

Warranty Information
Warranty 2 Years
Hardware
Bus Type USB 2.0
Chipset ID FTDI - FT232RL
Interface Serial
Port Style Cable Adapters
Ports 1
Performance
Data Bits 7, 8
FIFO 256 Bytes
Isolation 2500 Vrms
Max Baud Rate 921.6 Kbps
Maximum Cable Length 2.5 m [8.3 ft]
Parity None, Odd, Even, Mark, Space
Serial Protocol RS-232
Stop Bits 1, 2
Supported Protocols RS 232
Surge Protection 500W Bi-directional circuits
Connector(s)
Connector Type(s) 1 - DB-9 (9 pin, D-Sub) Male
1 - USB Type-A (4 pin) USB 2.0 Male
Software
Microsoft WHQL Certified Yes
OS Compatibility Windows® CE (4.2, 5.0, 6.0), XP Embedded, 98SE, 2000, XP, Vista, 7, 8, 8.1, 10
Windows Server® 2003, 2008 R2, 2012, 2012 R2, 2016
Mac OS® 10.6 to 10.13
Linux 2.4.x to 4.11.x LTS Versions only
Special Notes / Requirements
System and Cable Requirements One available USB 1.1 (or better) port
Power
Power Source USB-Powered
Environmental
Humidity 5~95% RH
Operating Temperature 0°C to 55°C (32°F to 131°F)
Storage Temperature -20°C to 85°C (-4°F to 185°F)
Physical Characteristics
Cable Length 2.5 m [8.3 ft]
Color Black
Enclosure Type Plastic
Product Height 20 mm [0.8 in]
Product Length 2.5 m [8.3 ft]
Product Weight 86 g [3 oz]
Product Width 40 mm [1.6 in]
Packaging Information
Shipping (Package) Weight 0.2 kg [0.4 lb]
What's in the Box
Included in Package 1 - USB to RS-232 Serial Adapter
1 - Driver CD
1 - Instruction Manual

Compatibility

View full OS compatibility
Windows® CE (4.2, 5.0, 6.0), XP Embedded, 98SE, 2000, XP, Vista, 7, 8, 8.1, 10
Windows Server® 2003, 2008 R2, 2012, 2012 R2, 2016
Mac OS® 10.6 to 10.13
Linux 2.4.x to 4.11.x LTS Versions only

Certifications

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Accessories

Product Support

Frequently Asked Questions

Installation

Some driver installation packages may require you to disable driver signature enforcement in Windows 8, which will allow unsigned driver packages to be installed on your system.

Note: Before you continue, save any open documents and close all open programs.

To disable driver signature enforcement, complete the following:

  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 finishes restarting, complete the following:

  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 your drivers.

Note: When you restart your computer after you install your drivers, driver signature enforcement will be enabled again. This does not prevent your newly installed drivers from working, but does prevent any other unsigned drivers from being installed until driver signature enforcement is disabled.

Some driver installation packages may require you to disable driver signature enforcement in Windows 8.1, which will allow unsigned driver packages to be installed on your system.

Note: Before you continue, save any open documents and close all open programs.

To disable driver signature enforcement, complete the following:

  1. Press the Windows key + C.
  2. Click Settings > Change PC Settings.
  3. In the left pane, click Update & Recovery.
  4. In the left pane, click Recovery.
  5. Under Advanced startup, click Restart now.

When your system finishes restarting, complete the following:

  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 your drivers.

Note: When you restart your computer after you install your drivers, driver signature enforcement will be enabled again. This does not prevent your newly installed drivers from working, but does prevent any other unsigned drivers from being installed until driver signature enforcement is disabled.­­­­­­­

You may need to disable Driver Signature Enforcement in Windows 10 to use some driver installation packages. When you disable this feature, you can install unsigned driver packages on your computer.

Note: Before you continue, save any open documents and close all of your programs. You will need to restart your computer to disable Driver Signature Enforcement.

To disable Driver Signature Enforcement, complete the following:

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

After your computer finishes restarting, complete the following:

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

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

Note: When you restart your computer after you install your drivers, driver signature enforcement will be enabled again. This does not prevent your newly installed drivers from working, but does prevent any other unsigned drivers from being installed until driver signature enforcement is disabled.­­­­­­­

Prior to installing this device, ensure that your operating system is up to date (for example, you have installed the most recent service pack).

To install the driver:

  1. Download the latest drivers from the StarTech.com website (http://www.startech.com/Support). You can find the part number and product ID on the product’s packaging.

Note: Windows will typically save the files to the Downloads folder that is associated with your user account (for example, C:\Users\your_name\Downloads).

  1. Once the download is complete, right-click the zip folder that you downloaded, select Extract All, and follow the on-screen instructions.
  2. Open the appropriate folder for your operating system.
  3. Right-click Setup.exe. 
  4. Click Run as Administrator.

Note: If the Run as Administrator option is not available, you might be attempting to run the installer from within the zipped file. Extract the files using the instructions in Step 2.

  1. Follow the on-screen prompts to install the device drivers and restart the computer when prompted.
  2. Your computer will automatically complete the driver installation and your device should be ready to use.

Prior to installing this device, ensure that your operating system is up to date (for example, you have installed the most recent service pack).

To install the driver:

  1. Download the latest drivers from the StarTech.com website (http://www.startech.com/Support). You can find the part number and product ID on the product’s packaging.

Note: Windows will typically save the files to the Downloads folder that is associated with your user account (for example, C:\Documents and Settings\your_name\My Documents\Downloads).

  1. Once the download is complete, right-click the zip folder that you downloaded, select Extract All, and follow the on-screen instructions.
  2. Open the appropriate folder for your operating system.
  3. Double-click Setup.exe.
  4. Follow the on-screen prompts to install the device drivers and restart the computer when prompted.
  5. Your computer will automatically complete the driver installation and your device should be ready to use.

How to

To confirm that Windows detects your USB device, complete the following:

  1. Press the Windows key+R, type devmgmt.msc, and press Enter.
  2. In Device Manager, under the appropriate heading, confirm that your expansion card is listed and that there isn't an exclamation mark next to it.  For example, a USB controller card would be under Universal Serial Bus controllers.

Your USB device is listed according to the name of the chipset. To determine the name of the chipset of your USB device, navigate to www.StarTech.com and look on the Technical Specifications tab for your product.

To confirm that the Mac OS detects your USB device, complete the following:

  1. Click the Apple icon.
  2. Click About This Mac.
  3. Click More Info or System Report.
  4. Under the appropriate heading, confirm that your USB device is listed and that there isn't an error. For example, a network card would be under Ethernet Cards.

You may need to refresh the System Information page after you plug in your device.  To do so, press Command R with the System Information page open.

Your USB device is listed according to the name of the chipset. To determine the name of the chipset of your USB device, navigate to www.StarTech.com and look on the Technical Specifications tab for your product.

Troubleshooting

When you troubleshoot issues with a serial device, there are some quick tests that you can complete to rule out potential problems. You can test to make sure that the following components are working correctly and are not the source of the issue:

  • Serial cables

  • Serial ports

  • Serial devices

To test your setup components, try the following:

  • Use the serial cable, serial port, and serial device in another setup to see if the problem is with the components or the setup.

  • Use a different serial cable, serial port, and serial device in your setup to see if the problem persists. Ideally, you should test a component that you know works in another setup.

When you test your cables, it is recommended that you do the following:

  • Test each cable individually.

  • Use short cables when you are testing.

When you test the serial ports and serial device, it is recommended that you do the following:

Note: Some serial devices work only if the COM port number is between a certain range. For example, COM1 to COM4.

To check whether or not an RS-232 serial port is working, perform an RS-232 loopback test by doing the following:

  1. If your serial port is not female, convert it by taking a female/female cable or gender changer and plugging it into the serial port.
  2. Take a metal paperclip or wire and cross pins 2 and 3. If you look closely at the female end, the pins should be numbered.
  3. Open a telnet session on the COM port number of the device that you are testing. To find out the COM port number, refer to the following FAQ: https://www.startech.com/faq/com-port-listing-windows.

Note: To open a telnet session on the COM port, you need a telnet client like PuTTY or Hyper Terminal. Windows XP comes with Hyper Terminal.

  1. When the session is open, anything you type into it you should see. The loopback test fails when you cannot see what you are typing.

If the loopback test fails, make sure that the serial cable or gender changer that you are using works and that the adapter is in the correct port. 

You can check multiple ports at the same time by opening multiple sessions, putting the loopback adapter on one port, and trying to type into each session.  When you can see what you are typing, you know that the COM port is working and you can see which port number the physical serial port is. Close the window for the port that you just tested to speed up the testing of the remaining serial ports.

For products related to this article, click here.

If the USB device does not work after your computer has been in extended hibernation, it is likely that Windows has automatically turned off the USB Root hub to save power. 

The steps below outline how to configure the USB root hub to stay on during hibernation, to prevent this from happening.
 

Windows 10 / 8

  1. On your keyboard, press the Windows key + X and select Control Panel.
  2. Click Hardware and Sound, then click Power Options.
  3. Click Change plan settings for the plan you want to change.
  4. Click Change advanced power settings.
  5. Click the plus sign (+) next to “USB settings” and “USB selective suspend setting” to expand the options and change the setting to Disabled.
  6. Click OK to apply the setting.

Note: You may need to disconnect and re-connect your USB device after applying these settings to re-establish the connection.

Windows 7 / Vista

  1. Click the Start button and select Control Panel.
  2. Click Hardware and Sound, then click Power Options.
  3. Click Change plan settings for the plan you want to change.
  4. Click Change advanced power settings.
  5. Click the plus sign (+) next to “USB settings” and “USB selective suspend setting” to expand the options and change the setting to Disabled.
  6. Click OK to apply the setting.

Note: You may need to disconnect and re-connect your USB device after applying these settings to re-establish the connection.

Windows XP

  1. On your desktop, right-click the My Computer icon and select Properties.
  2. Click the Device Manager tab.
  3. Expand Universal Serial Bus controllers by clicking the arrow to the left of it.
  4. Right-click the first USB Root Hub device and select Properties.
  5. Click the Power Management tab.
  6. Clear the box next to Allow the computer to turn off this device to save power.
  7. Click OK to apply the setting.
  8. Repeat steps 4-7 for any remaining devices in the Universal Serial Bus Controllers section with “Root Hub” in the name.

Note: You may need to disconnect and re-connect your USB device after applying these settings to re-establish the connection.