---
name: "ubsa"
section: "4"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["linux", "freebsd", "openbsd"]
url: "https://new.carta.tech/ubsa"
---

# ubsa(4)

USB support for Belkin serial adapters

## NAME

**ubsa** – USB support for Belkin serial adapters

## SYNOPSIS

**device** **usb** **device** **ucom** **device** **ubsa**

In [loader.conf(5)](/loader.conf/5.md): **ubsa\_load="YES"**

## DESCRIPTION

The **ubsa** driver provides support for the USB-to-RS232 Bridge chip used by a variety of serial adapters from Belkin and other vendors.

The device is accessed through the [ucom(4)](/ucom/4.md) driver which makes it behave like a [tty(4)](/tty/4.md).

## HARDWARE

The **ubsa** driver supports the following adapters:

- AnyData ADU-500A EV-DO modem

- AnyData ADU-E100A (no EV-DO mode support)

- Belkin F5U103

- Belkin F5U120

- e-Tek Labs Kwik232

- GoHubs GoCOM232

- Peracom single port serial adapter

## FILES

- */dev/ttyU\**

  for callin ports

- */dev/ttyU\*.init*

  - */dev/ttyU\*.lock*

  corresponding callin initial-state and lock-state devices

- */dev/cuaU\**

  for callout ports

- */dev/cuaU\*.init*

  - */dev/cuaU\*.lock*

  corresponding callout initial-state and lock-state devices

## SEE ALSO

[tty(4)](/tty/4.md), [ucom(4)](/ucom/4.md), [usb(4)](/usb/4.md)

## HISTORY

The **ubsa** driver appeared in FreeBSD 5.0. The [uplcom(4)](/uplcom/4.md) manual page was adopted from NetBSD by Tom Rhodes ⟨*trhodes@FreeBSD.org*⟩ in April 2002 and modified for the **ubsa** driver by Alexander Kabaev ⟨*kan@FreeBSD.org*⟩ in October 2002.

## AUTHORS

The **ubsa** driver was written by Alexander Kabaev ⟨*kan@FreeBSD.org*⟩.