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FTDI USB to serial adapter with DB9 connector lets you connect RS422 and RS485 devices to your computer’s USB port.
  • Supports data transfer speeds up to 230 Kbps—double the speed of a built-in serial port
  • Automatically reassigns COM values to each port to avoid additional configuration
  • USB-powered, so no bulky or obtrusive external power supply is required
  • Double shielding protects against EMI/RFI line noise that can distort or destroy data
  • Compatible with Windows, Mac and Linux—works with most computers
  • 3-year limited warranty


Connects a Printer, Router or Other DTE Serial Device to Your Computer’s USB-A Port
This 30-inch USB to RS485 adapter cable turns your computer’s USB port into an RS422 or RS485 serial port and avoids the expense of upgrading your reliable serial devices. No external power source is needed. Just connect the cable to your computer and insert the included CD into your computer’s CD drive in order to launch the driver and assign the cable a COM port. It supports USB 2.0 specifications and data transfer speeds up to 230 Kbps, which is almost twice as fast as a built-in serial port. It is backward compatible with USB 1.1 devices. Note: The U209-30N-IND will pull power from the host device. If connected to a USB2.0 host, 0.5A of max power will be provided. If connecting to USB3.0 host, 0.9A of power will be provided. If your device is not working properly, be sure you are connecting to the proper USB port.
COM Retention Feature for Convenient Reassigning of COM Values to Ports
The hot-swappable USB to RS422 adapter with built-in FTDI chipset offers COM retention. It automatically reassigns the same COM port values to each port, so when the cable is disconnected or the system is rebooted, no additional configuration is needed. The FTDI USB to serial adapter also supports RS485 auto-transceiver turn around with unique featured ATTA hardware, as well as remote wake-up and power management. A DB9-to-terminal-block adapter is included for making hardwire connections.
Double Shielding Protects Your Data from Destructive Line Noise
Foil and braid shielding helps fight against electromagnetic interference and radio frequency interference (EMI/RFI) that impedes your signal and can distort or destroy data. The auto-sensing feature solves DCE/DTE conflicts without the need for cross-wired serial cables or adapters.
3-Year Warranty
The U209-30N-IND is backed by a 3-year warranty, ensuring reliability and performance.

System Requirements

  • Windows, Mac or Linux
  • Computer with an available USB port

Package Includes

  • U209-30N-IND USB to RS485/RS422 FTDI Serial Adapter Cable, 30 in.
  • DB9 to terminal block adapter
  • Driver CD
  • Owner’s manual
RoHS compliant


UPC Code037332210234
TechnologyUSB 2.0 (High Speed)
Bus Powered  Yes
Material of ConstructionPCB, PVC
Cable Jacket ColorBlack
Cable Jacket RatingVW-1
Cable Length (ft.)2
Cable Length (in.)30
Shipping Dimensions (hwd / in.)1.22 x 4.65 x 4.13
Shipping Weight (lbs.)0.18
Unit Dimensions (hwd / in.)0.000 x 0.000 x 0.000
Unit Packaging TypeBox
Unit Weight (lbs.)0.13
Operating Temperature Range32° to 140°F (0° to 60°C)
Storage Temperature Range-4° to 176°F (-20° to 80°C)
Relative Humidity0% to 80% RH, Non-Condensing
Side A - Connector 1USB A (MALE)
Side B - Connector 1DB9 (MALE)
Connector PlatingNickel
Contact Plating  Gold
USB SpecificationUSB 2.0 (up to 480 Mbps)
Remote Wakeup SupportYes
Driver RequiredYes
Product CertificationsNOM (Mexico)
Product ComplianceRoHS; CE (Europe); REACH; WEEE; FCC (USA)
Product Warranty Period (Worldwide)3-year limited warranty

Questions & Answers

COM retention allows the same COM port number to be automatically assigned each time the serial adapter is connected to a USB port on your system (or your system is rebooted). Without COM Retention, you would have to remember which port to connect the adapter.
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