---
name: "udav"
section: "4"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["linux", "freebsd", "openbsd"]
url: "https://new.carta.tech/udav/4"
---

# udav(4)

Davicom DM9601 10/100 USB Ethernet device

## NAME

**udav** – Davicom DM9601 10/100 USB Ethernet device

## SYNOPSIS

**udav\*  at uhub?** **amphy\* at mii?**

## DESCRIPTION

The **udav** driver provides support for USB Ethernet adapters based on the Davicom DM9601 USB-ether bridge chip.

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

- Corega FEther USB-TXC

  - HenTong WK-668

  - Konig CMP-NWUSB10

  - ShanTou ST268

  - ShanTou ZT6688

  - ShanTou ADM8515

  The **udav** driver also supports CoreChip RD9700. As many of these units ship with the same MAC address, it is highly recommended to use [ifconfig(8)](/ifconfig/8.md) **lladdr** to set the address manually, or **lladdr** **random** to assign a random address.

For more information on configuring this device, see [ifconfig(8)](/ifconfig/8.md).

## SEE ALSO

[amphy(4)](/amphy/4.md), [arp(4)](/arp/4.md), [ifmedia(4)](/ifmedia/4.md), [mii(4)](/mii/4.md), [netintro(4)](/netintro/4.md), uhub(4), [usb(4)](/usb/4.md), [hostname.if(5)](/hostname.if/5.md), [ifconfig(8)](/ifconfig/8.md) *Davicom DM9601 data sheet*, http://www.davicom.com.tw/big5/download/Data%20Sheet/DM9601-DS-P01-930914.pdf.

## HISTORY

The **udav** device driver first appeared in OpenBSD 3.7.

## AUTHORS

The **udav** driver was written by Shingo WATANABE ⟨*nabe@nabechan.org*⟩ and ported to OpenBSD by Jonathan Gray ⟨*jsg@openbsd.org*⟩.

RD9700 support by Takayoshi SASANO ⟨*uaa@uaa.org.uk*⟩.

## BUGS

The RD9700 sometimes lacks zero-length packets to terminate USB transactions, which can cause USB IOERRORs.