BWN(4) FreeBSD Kernel Interfaces Manual BWN(4)


bwnBroadcom BCM43xx IEEE 802.11b/g wireless network driver


To compile this driver into the kernel, place the following lines in your kernel configuration file:

device siba_bwn
device bwn
device wlan
device wlan_amrr
device firmware

Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):



The bwn driver provides support for Broadcom BCM43xx based PCI/CardBus network adapters.

It 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).

This driver requires firmware to be loaded before it will work. The ports/net/bwn-firmware-kmod port needs to be installed before ifconfig(8) will work. Most cases you need to use bwn_v4_ucode module but if you are a LP (low power) PHY user please uses bwn_v4_lp_ucode module.


The bwn driver supports Broadcom BCM43xx based wireless devices, including:
Card Chip Bus Standard
Apple Airport Extreme BCM4318 PCI b/g
ASUS WL-138g BCM4318 PCI b/g
Buffalo WLI-CB-G54S BCM4318 CardBus b/g
Dell Wireless 1390 BCM4311 Mini PCI b/g
Dell Wireless 1470 BCM4318 Mini PCI b/g
Dell Truemobile 1400 BCM4309 Mini PCI b/g
HP Compaq 6715b BCM4312 PCI b/g
HP nx6125 BCM4319 PCI b/g
Linksys WPC54G Ver 3 BCM4318 CardBus b/g
Linksys WPC54GS Ver 2 BCM4318 CardBus b/g
US Robotics 5411 BCM4318 CardBus b/g

Users of older Broadcom chipsets (BCM4301, BCM4303 and BCM4306 rev 2) must use bwi(4) because the v4 version of the firmware does not support these chips. The newer firmware is too big to fit into these old chips.


Join an existing BSS network (i.e., connect to an access point):

ifconfig wlan create wlandev bwn0 inet \ 
    netmask 0xffffff00

Join a specific BSS network with network name “ my_net”:

ifconfig wlan create wlandev bwn0 ssid my_net up

Join a specific BSS network with 64-bit WEP encryption:

ifconfig wlan create wlandev bwn0 ssid my_net \ 
        wepmode on wepkey 0x1234567890 weptxkey 1 up


Tunables can be set at the loader(8) prompt before booting the kernel or stored in loader.conf(5).
This tunable disables MSI support on the hardware. The default value is 0.
This tunable enables DMA operations on the hardware. If the value is 0, PIO mode would be used. The default value is 1.


The bwn driver first appeared in FreeBSD 8.1.


The bwn driver was written by Weongyo Jeong <weongyo@FreeBSD.org>.


Some LP PHY devices have DMA operation problems that in that case try to use PIO mode.
February 15, 2011 FreeBSD