AN(4)

💖 AN(4) — the Aironet wireless adapter driver, bestie edition 💖

okay so this is the manual page for an, which lives in the Kernel Interfaces Manual section of the FreeBSD docs (that's the "4" in AN(4), iykyk). Buckle up, we're talking about a wireless network adapter driver from Aironet Communications. Yes it's old. Yes it's iconic. Let's go ✨

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🌸 NAME 🌸

an — the Aironet Communications 4500/4800 wireless network adapter driver</p> 🦋

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✨ SYNOPSIS ✨

So if you wanna bake this driver into your kernel, you drop these lines into your kernel configuration file:

device an
device wlan

Orrrr, if you'd rather load it as a module at boot time (lowkey the easier vibe), you put this line in loader.conf(5):

if_an_load="YES"

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🚨 DEPRECATION NOTICE 🚨

bestie. sit down. This driver is scheduled for removal prior to the release of FreeBSD 13.0. It's giving end of an era 😭

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💅 DESCRIPTION 💅

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

• Aironet Communications 4500 and 4800 series
• Cisco Aironet 340 and 350 series
• Xircom Wireless Ethernet Adapter

Support for these devices include the ISA, PCI and PCMCIA 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, PCI and PCMCIA devices are all based on the same core PCMCIA modules and all have the same programming interface, however — and this is the plot twist — unlike the Lucent WaveLAN/IEEE cards, the ISA and PCI cards appear to the host as normal ISA and PCI devices and do not require any PCCARD support. no cap 🫶

The PCMCIA Aironet cards require PC Card support, including the kernel pccard(4) driver. 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, btw.) 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 configuration and the NIC's switch settings must agree. Like, they have to match, fr fr. PCI cards require no switch settings of any kind and will be automatically probed and attached. main character behavior honestly 👑

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 receive either 802.11 or 802.3 frames. Transmit speed is selectable between 1Mbps, 2Mbps, 5.5Mbps, 11Mbps or "auto" (the NIC automatically chooses the best speed). slay 💅

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

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

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🩺 DIAGNOSTICS 🩺

• an%d: init failed — The Aironet card failed to become ready after an initialization command was issued. she's not waking up 😭
• an%d: failed to allocate %d bytes on NIC — The driver was unable to allocate memory for transmit frames in the NIC's on-board RAM. no room, no vibes 💀
• an%d: device timeout — The Aironet card failed to generate an interrupt to acknowledge a transmit command. ghosted you, literally 🙈

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👀 SEE ALSO 👀

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

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📜 HISTORY 📜

The an device driver first appeared in FreeBSD 4.0. a legend from day one ✨

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🎀 AUTHORS 🎀

The an driver was written by Bill Paul <wpaul@ee.columbia.edu>. thank you king 🫶

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and that's the whole page, bestie!! 💖 this one shipped on the Debian side of things, dated July 16, 2005 — yeah, she's vintage, and we love her for it. go forth and configure responsibly 🌈⭐