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

# if\_zyd(4)

ZyDAS ZD1211/ZD1211B USB IEEE 802.11b/g wireless network driver

## NAME

**zyd** – ZyDAS ZD1211/ZD1211B USB IEEE 802.11b/g wireless network driver

## SYNOPSIS

**device** **ehci** **device** **uhci** **device** **ohci** **device** **usb** **device** **zyd** **device** **wlan** **device** **wlan\_amrr**

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

## DESCRIPTION

The **zyd** driver provides support for wireless network adapters based around the ZyDAS ZD1211 and ZD1211B USB chips.

**zyd** supports **station** and **monitor** mode operation. Only one virtual interface may be configured at any time. For more information on configuring this device, see [ifconfig(8)](/ifconfig/8.md).

## HARDWARE

The **zyd** driver supports the following USB 802.11b/g wireless network devices based on ZyDAS ZD1211/ZD1211B controllers:

- 3COM 3CRUSB10075

- Acer WLAN-G-US1

- Airlink+ AWLL3025

- Airlink 101 AWLL3026

- AOpen 802.11g WL54

- Asus A9T integrated wireless

- Asus WL-159g

- Belkin F5D7050 v.4000

- Billion BiPAC 3011G

- Buffalo WLI-U2-KG54L

- CC&C WL-2203B

- DrayTek Vigor 550

- Edimax EW-7317UG

- Edimax EW-7317LDG

- Fiberline Networks WL-43OU

- iNexQ UR055g

- Linksys WUSBF54G

- Longshine LCS-8131G3

- MSI US54SE

- MyTek MWU-201 USB adapter

- Philips SNU5600

- Planet WL-U356

- Planex GW-US54GZ

- Planex GW-US54GZL

- Planex GW-US54Mini

- Safecom SWMULZ-5400

- Sagem XG 760A

- Sagem XG 76NA

- Sandberg Wireless G54 USB

- Sitecom WL-113

- SMC SMCWUSB-G

- Sweex wireless USB 54 Mbps

- Tekram/Siemens USB adapter

- Telegent TG54USB

- Trendnet TEW-424UB rev A

- Trendnet TEW-429UB

- TwinMOS G240

- Unicorn WL-54G

- US Robotics 5423

- X-Micro XWL-11GUZX

- Yakumo QuickWLAN USB

- Zonet ZEW2501

- ZyXEL ZyAIR G-202

- ZyXEL ZyAIR G-220

## EXAMPLES

The following example configures zyd0 to join any BSS network using WEP key “0x1deadbeef1”, channel 11:

```
ifconfig wlan create wlandev zyd0 channel 11 \
    wepmode on wepkey 0x1deadbeef1 weptxkey 1 \
    inet 192.0.2.20/24
```

Join an existing BSS network, *my\_net*:

```
ifconfig wlan create wlandev zyd0 192.0.2.20/24 \
    ssid my_net
```

## DIAGNOSTICS

- zyd%d: could not load firmware (error=%d)

  An error occurred while attempting to upload the firmware to the onboard microcontroller unit.

- zyd%d: could not send command (error=%s)

  An attempt to send a command to the firmware failed.

- zyd%d: sorry, radio %s is not supported yet

  Support for the specified radio chip is not yet implemented in the driver. The device will not attach.

- zyd%d: device version mismatch: 0x%x (only \>= 43.30 supported)

  Early revisions of the ZD1211 chipset are not supported by this driver. The device will not attach.

- zyd%d: device timeout

  A frame dispatched to the hardware for transmission did not complete in time. The driver will reset the hardware. This should not happen.

## SEE ALSO

[intro(4)](/intro/4.md), [netintro(4)](/netintro/4.md), [usb(4)](/usb/4.md), [wlan(4)](/wlan/4.md), [wlan\_amrr(4)](/wlan_amrr/4.md), [wlan\_ccmp(4)](/wlan_ccmp/4.md), [wlan\_tkip(4)](/wlan_tkip/4.md), [wlan\_wep(4)](/wlan_wep/4.md), [networking(7)](/networking/7.md), [ifconfig(8)](/ifconfig/8.md), [wpa\_supplicant(8)](/wpa_supplicant/8.md)

## AUTHORS

The original **zyd** driver was written by Florian Stoehr ⟨*ich@florian-stoehr.de*⟩, Damien Bergamini ⟨*damien@openbsd.org*⟩, and Jonathan Gray ⟨*jsg@openbsd.org*⟩.

## CAVEATS

The **zyd** driver does not support a lot of the functionality available in the hardware. More work is required to properly support the IBSS and power management features.