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AN(4)		       FreeBSD Kernel Interfaces Manual			 AN(4)

     an	-- Aironet Communications 4500/4800 wireless network adapter driver

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

	   device an
	   device wlan

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


     The an driver provides support for	Aironet	Communications 4500 and	4800
     wireless network adapters and variants, including the following:

	   o   Aironet Communications 4500 and 4800 series
	   o   Cisco Aironet 340 and 350 series

     Support for these devices include the ISA and PCI varieties.  The Aironet
     4500 series adapters operate at 1 and 2Mbps while the Aironet 4800	series
     and Cisco adapters	can operate at 1, 2, 5.5 and 11Mbps.  The ISA and PCI
     devices are all based on the same core PCMCIA hardware and	all have the
     same programming interface.  The ISA and PCI cards	appear to the host as
     normal ISA	and PCI	devices.

     ISA cards can either be configured	to use ISA Plug	and Play or to use a
     particular	I/O address and	IRQ by properly	setting	the DIP	switches on
     the board.	 (The default switch setting is	for Plug and Play.)  The an
     driver has	Plug and Play support and will work in either configuration,
     however when using	a hard-wired I/O address and IRQ, the driver configu-
     ration and	the NIC's switch settings must agree.  PCI cards require no
     switch settings of	any kind and will be automatically probed and at-

     All host/device interaction with the Aironet cards	is via programmed I/O.
     The Aironet devices support 802.11	and 802.3 frames, power	management,
     BSS (infrastructure) and IBSS (ad-hoc) operation modes.  The an driver
     encapsulates all IP and ARP traffic as 802.11 frames, however it can re-
     ceive either 802.11 or 802.3 frames.  Transmit speed is selectable	be-
     tween 1Mbps, 2Mbps, 5.5Mbps, 11Mbps or "auto" (the	NIC automatically
     chooses the best speed).

     By	default, the an	driver configures the Aironet card for infrastructure

     For more information on configuring this device, see ifconfig(8).

     an%d: init	failed	The Aironet card failed	to become ready	after an ini-
     tialization command was issued.

     an%d: failed to allocate %d bytes on NIC  The driver was unable to	allo-
     cate memory for transmit frames in	the NIC's on-board RAM.

     an%d: device timeout  The Aironet card failed to generate an interrupt to
     acknowledge a transmit command.

     altq(4), arp(4), miibus(4), netintro(4), wlan(4), ancontrol(8),

     The an device driver first	appeared in FreeBSD 4.0.

     The an device driver was removed in FreeBSD 14.0.

     The an driver was written by Bill Paul <>.

FreeBSD	13.0			 July 16, 2005			  FreeBSD 13.0


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