Sounds about right. Let's check the exact details - according to http://acx100.erley.org/acx_fw/acx1xx.htm -BlackAdder wrote:copied the firmware to /lib/firmware and renamed the .bin files as recommended.
modprobe acx
this loaded without errors and the card light flashed - presumably as the result of the firmware being downloaded.
RADIO11.BIN renamed to tiacx100r11 and
WLANGEN.BIN renamed to tiacx100
... but there's a report here http://sourceforge.net/forum/forum.php? ... _id=257272
that there's a different DWL-650+ (with Maxim radio) which needs different firmware.
dmesg will show "requesting firmware image 'tiacx100c0D'" The critical part is "0d" If so, you need -
ACX100.bin renamed tiacx100 and
RADIO0d.BIN renamed tiacx100r0d