Broadcom bcm43xx 無線網卡安裝筆記

要驅動具有 Broadcom 生產的無線網卡晶片，需要額外安裝 firmware 到系統才能正確驅動，根據 Broadcom 版權聲明，你只能由 Broadcom 提供的驅動程式裡取得。下面這段說明是由 linuxwireless.org 裡擷取出來的。

The Broadcom wireless chip needs software, called "firmware", that runs on the wireless chip itself during operation. This firmware is copyrighted by Broadcom and must be extracted from Broadcom's proprietary drivers. To get such firmware on your system, you must download the driver from a legal distribution point, as noted below. Then you must extract the firmware from that Broadcom driver by using b43-fwcutter (or bcm43xx-fwcutter) and install it in the special directory for firmware - usually /lib/firmware. Please note that the firmware from the binary drivers is copyrighted by Broadcom Corporation and must not be redistributed.

不廢話了，開始進行安裝吧。首先用lspci指令確定 Linux 有抓到這張網卡

00:0b.0 Network controller: Broadcom Corporation BCM4318 [AirForce One 54g] 802.11g Wireless LAN Controller (rev 02)

透過 /etc/modprobe.conf 得知我的 eth1 是用 bcm43xx 模組驅動

shell># cat /etc/modprobe.conf
alias eth0 sis900
alias scsi_hostadapter pata_sis
alias eth1 bcm43xx

但啟動 eth1 時，卻出現下面這段錯誤訊息，這表示缺少了 bcm43xx_microcode5.fw 這個東西

bcm43xx: Error: Microcode "bcm43xx_microcode5.fw" not available or load failed.

接下來請使用瀏覽器連結到 http://linuxwireless.org/en/users/Drivers/b43#Other_distributions_that_are_not_mentioned_above
透過這張表可以得知 bcm43xx 模組該使用哪個版本的 Firmware extractor，他也貼心的提供操作指示


我直接貼上 linuxwireless 的操作說明，直接照做就可以了


完成 firmware extract 的動作後，就可以開始設定無線網路
shell># iwconfig eth1 ssid "my ap" key 0123456789
shell># ifconfig eth1 192.168.0.2 netmask 255.255.255.0 up
shell># ifconfig

eth1      Link encap:Ethernet  HWaddr 00:17:31:F5:42:F0
          inet addr:192.168.0.2  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::217:31ff:fef5:42f0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:507 errors:0 dropped:604 overruns:0 frame:0
          TX packets:327 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:42311 (41.3 KiB)  TX bytes:25013 (24.4 KiB)
          Interrupt:12

參考文獻
linuxwireless.org#b43