StarTech 1ft (30cm) USB to Null Modem Serial Adapter Cable 1P1FFCN-USB-SERIAL

The StarTech 1P1FFCN-USB-SERIAL is a 1-foot USB-to-null-modem serial adapter cable for technicians and users who need a short USB connection to serial DCE equipment.

Recommended For

• PLC and industrial-automation technicians connecting a laptop to RS-232 equipment that needs null-modem wiring; the built-in null-modem function avoids carrying a separate crossover cable or adapter.
• IT and field-service staff who occasionally connect a USB-A laptop to nearby RS-232 devices, such as industrial equipment, and want the adapter’s transmit/receive LEDs to help check serial activity while troubleshooting.
• Technicians who reconnect the same serial device to the same computer and want COM-port retention to reduce port reassignment during routine disconnects or restarts.

Real-World Use Scenarios

• When a network appliance with a DB9 console port requires null-modem wiring, connect it to a laptop and use terminal software to view its console for setup or troubleshooting. Confirm the appliance’s port wiring and terminal settings first; not every console port uses a null-modem connection.
• For a serial instrument that uses DTE wiring, connect it to a computer’s USB-A port to send commands or receive measurement data through serial software. The instrument’s documentation should confirm that a null-modem connection is required.
• When diagnosing a device through its serial console because network access is unavailable, connect the laptop and open a terminal session to inspect startup messages or interact with the device locally. This depends on the device supporting a DB9 RS-232 console with null-modem wiring.
• For a direct serial link between two computers, use the cable on the computer that lacks a built-in DB9 serial port, then run compatible terminal or transfer software on both systems. The connection requires matching serial settings and null-modem wiring at the other end.

Spec Summary