USB-to-DB9 (RS-232) Cable UGREEN CR104 3 m — USB to serial adapter cable

UGREEN CR104 is a 3 m USB-to-DB9 (RS-232) cable that provides a direct connection between a computer USB port and devices with a 9-pin DB9 serial interface. The cable is intended to bridge modern USB-only computers and legacy serial equipment such as industrial controllers, POS terminals, modems and measurement instruments, enabling data exchange over the RS-232 protocol without opening the host device or installing an internal serial card.

Advantages

The integrated adapter cable combines the USB interface and a DB9 connector in a single, ready-to-use assembly, eliminating the need for separate adapters or external power supplies. With a 3 meter length it offers extended reach and flexibility for connecting devices located away from the host computer. The cable implements standard RS-232 signaling levels to maintain compatibility with a wide range of serial devices and supports plug-and-play installation on most operating systems with available drivers.

Suitable for

• Connecting industrial controllers and PLCs to laptop or desktop computers
• Linking POS terminals, receipt printers and barcode scanners to modern PCs
• Interfacing modems, measurement instruments and laboratory equipment
• Field service, maintenance and configuration of legacy serial devices

Key specifications

• Cable type: USB to DB9 (RS-232) serial adapter cable
• Length: 3 m
• Connector A: USB (type specified by manufacturer)
• Connector B: 9-pin male DB9 serial connector
• Supported interface: RS-232 serial communication
• Data direction: full-duplex serial data transmission
• Compatibility: designed for use with RS-232-compliant devices and host computers with USB ports

How to use

Connect the USB end to an available USB port on the computer and attach the DB9 connector to the serial port of the target device. If required by the operating system, install the supplied or downloadable driver to enable the virtual COM port. After driver installation the cable appears as a COM port in system device manager or serial terminal software; configure baud rate, parity, data bits and stop bits to match the connected device settings. Ensure secure connection of screws on the DB9 connector where applicable to prevent accidental disconnects.

Использование и ограничения

Use the cable within its specified length for reliable signal integrity. Avoid routing the cable near high-voltage lines or strong electromagnetic sources to reduce interference. For devices that require hardware flow control, verify that the necessary RS-232 handshake lines are supported by both the cable and the connected equipment.