"People who had problems with unsupported Atheros devices (single chip variants found in recent laptops, macbooks, etc.) should get the latest code from CVS and test it..." OpenBSD Reyk Floeter announced regarding recent improvements to his reverse engineered HAL adding support for 11b mode. He noted that the new code wasn't without fault yet, adding, "hacked and tested in the Melbourne Museum during the AUUG 2007..." Reyk explained the changes in his commit message:

"The newer single chip Atheros wireless chipsets like the AR5424, AR2423 etc. are mostly compatible to the AR5212 but use a different algorithm to set the 2GHz RF channel, that's why they didn't work in OpenBSD. I figured out that the channels were set with an offset, setting channel 11 in the driver caused the hardware to set channel 5 etc. Because I didn't figure out the pattern to fix the algoritm yet, I fixed it in a workaroundish way by defining a small 'table' with offsets for the 11b channels to get the right results. For example, if we want to set channel 11 (2462MHz), we add an offset of -30MHz, and feed the result (2432MHz ^= channel 5) into the unmodified AR5212/AR5112 RF setup function.

"Long description for a commit message, but it needed some time to figure it out. It is still not perfect, needs some more work, and it doesn't work in all cases; but it allows to use newer chipsets in 11b mode restricted to 1 or to 2Mbit/s. 11a mode seems to work without problems so far."