On 5/1/09, Gustau Perez <gpe...@entel.upc.edu> wrote: > > Hi, > > I think this is right place to post, if it is not, please let me know. > > I'm experiencing problems with two different devices using if_rum. > One is a Hercules Guillemot and the other is a Linksys Cisco WUSB54GC > > The first one is about sensitivity, which is very low: for example, > I'm detecting just two or three networks around me (with windows both > usb devices detect around 14 or 15 networks) and the reported signal is > very low.Placing the sensor very near to my wireless network AP (which > is a FreeBSD machine with atheros card placing the txpower to 20) > reports a signal quality of 50% or 60%. > > Linux presents the same problem (my wife's laptop with ubuntu shows > the same figures, more or > > The other one is that having such a low sensitivity makes those > dongles unusable when making large transfers, mostly when using scp/sftp > or sshfs (samba seems to make it work better for longer transfer, but > finally the problem appears). At some given point, the dongles seem to > lose contact with the AP (making ifconfig shows that wlan0 is still > associated), waiting for a period of time (usually one or two minutes) > the transfer continues. Probably both problems are related. > > In order to debug the problem I tried looking dmesg in both my AP and > my laptop (no trace). Tried looking at the ssh logs (when making large > transfers, no clue). In the only place I found something was in the > samba logs, only saying that there was a problem with the transfer > (broken pipe, the socket is closed). > > So : > > In the linux world, I found that the register which controls the > sensitivity is bbp17 : > > http://209.85.229.132/search?q=cache:H8W6R5Ds3mYJ:forum.aircrack-ng.org/index.php%3Ftopic%3D2235.0+bbp17+ralink+linux&cd=1&hl=ca&ct=clnk&gl=es&client=firefox-a > > Tried looking in > /usr/src/sys/dev/usb/wlan/if_rum.c, but I got lost. Tried with sysctl -a > | grep rum or grep wlan0, but no MiB related to sensitivity appeared. > > Is there anything I can try ? How can I force bbp 17 to get 0 value ? > Tried with rum_def_bbp in if_rum.c, changing 17 to 0. No luck.
There is several places where bbp17 is changed. Last time I was exploring rum I found that it lacks bbp auto tuning. [Failed to implement it, because in meantime I broke chip :)] -- Paul _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
