StarTech.com USB to Null Modem Serial Adapter Cable, FTDI, USB-A to DB9 RS232

StarTech.com 1ft (30cm) USB to Null Modem Serial Adapter | FTDI Chipset

The StarTech.com 1ft (30cm) USB to Null Modem Serial Adapter Cable, COM Retention, FTDI, USB-A to DB9 RS232, Interchangeable DB9 Nuts/Screws, Windows/macOS/Linux adds an RS-232 null modem port to modern computers. It is designed for engineers, industrial technicians, and legacy hardware users. The key USP is built-in COM port retention, which prevents configuration drift after disconnection or reboot.

This adapter resolves DCE/DTE conflicts without extra cross-over cables. It connects via a standard USB-A port to a DB-9 female serial connector. The 30 cm cable length reduces desk clutter while maintaining reach to peripheral devices. For UK buyers, verify physical connector clearance and mounting screw requirements before purchase.

Slim Specifications

Stable COM Port Assignment

The adapter features COM retention. It automatically reassigns the same COM port value if you disconnect and reconnect the cable or reboot the system. This prevents software reconfiguration in industrial control or diagnostic workflows. Because the FTDI chipset is widely recognised, driver conflicts are less common than with generic controllers. In practice, this reduces downtime during field service or lab testing.

Interchangeable DB-9 Hardware Fitting

You can secure the adapter to a serial device using pre-installed removable DB-9 nuts. Alternatively, install the included slotted D-Sub thumbscrews for compatibility with other serial peripherals or cables. This flexibility helps when mounting in racks or connecting to legacy equipment with non-standard recesses. Check that your device’s DB-9 port orientation suits a straight connector form factor.

Real-Time LED Diagnostics

Data transmission and reception LEDs provide live activity monitoring. A separate USB LED confirms successful enumeration on the host computer. These indicators aid rapid troubleshooting of cable, port, or driver issues. Because you can see link status at a glance, fault isolation is faster in busy maintenance environments.

Wide OS Coverage and Driver Support

The adapter supports Windows, macOS, ChromeOS, and Linux. Drivers auto-install on Windows 7 and newer, macOS 10.15 and above, and most Linux distributions. It also supports Windows Server 2008 R2 through 2022. If you use older OS versions, confirm driver availability before ordering. This breadth helps mixed-IT estates common in UK facilities.

Rugged Construction and EMI Protection

TPE housing and Level-4 ESD protection (15kV air, 8kV contact) improve durability. Copper shielding reduces electromagnetic and radio frequency interference. Gold-plated connectors enhance signal conductivity and corrosion resistance. The cable is rated for 0–95% operating humidity, suiting demanding workshop conditions.

Box contents

• StarTech.com 1ft USB to Null Modem Serial Adapter Cable
• Interchangeable DB-9 nuts and slotted D-Sub thumbscrews

Check before you buy

• Confirm your device uses a standard DB-9 serial port and requires a null modem (DCE) connection.
• Verify physical clearance for straight connector orientation and screw mounting.
• Ensure your operating system version matches the supported lists above.
• Check whether your application requires specific baud rates up to 921.6 Kbit/s.

Frequently Asked Questions

Q: Does this adapter require an external power source?

A: No, it is bus-powered via the USB-A port.

Q: Is the DB-9 connector wired as a null modem?

A: Yes, it provides RS-232 DCE communication with crossed TX/RX.

Q: Will the COM port number change after reboot?

A: No, COM retention reassigns the same port automatically.

Q: Are Linux drivers included?

A: Yes, Linux is supported; drivers typically auto-load on modern distributions.

Q: Is the cable shielded for industrial use?

A: Yes, copper shielding reduces EMI/RFI, and ESD protection is Level-4.

The Consultant’s verdict & warranty

Buy this adapter if you need a reliable, short-length USB to null modem serial connection for industrial, lab, or legacy equipment tasks. The FTDI chipset, COM retention, and interchangeable DB-9 hardware make it a practical choice for UK technical environments. Covered by the standard Manufacturer Warranty.