On 20 August 2014 16:33, PseudoCylon <moonlightak...@yahoo.ca> wrote:
> On Wed, Aug 20, 2014 at 1:29 PM, Adrian Chadd <adr...@freebsd.org> wrote:
>> Are you seeing RX CRC errors for all rates? CCK? OFDM? HT? At all distances?
> CCK not sure, OFDM and HT yes. And at wide range of distances. (Tx
> rates usually hit mcs 12 to 14 with 2s ht20 ap)
>> There's a handful of things we can look at to see what's causing it
>> once some more digging is done.
>> (Eg, HT? could be guard interval. OFDM has similar issues, there's
>> typically ways to configure how much time between each symbol is left
>> before transmitting the next one. It may not be doing CTS-to-self, or
>> it may not be advertising the right thing via NAV, or it may be
>> ignoring CCK, or the receive gain tables are all messed up, etc.)
> I have looked into stuff I was able to dig out from other src codes,
> ie protection, ifs, nav, bk slot. (Because I do not have datasheet,
> every thing is based on my guesses.) One thing I could not figure out
> is if on-chip memory is properly allocated for rx pkt. (It seems
> memory can be allocated for different things, ie beacon, enc keys).

So CRC errors are pretty normal with wifi. Even a tiny bit of
interference generates CRC errors. That's why there's an ACK and retry
mechanism. :P

If you're hitting MCS 12 then you're doing pretty well. A-MPDU will
see lots of CRC errors just because of how long the transmissions are
and how easily corrupted things can get. That's again why there's a
quick retry mechanism for things.

What %age errors are you seeing?

freebsd-wireless@freebsd.org mailing list
To unsubscribe, send any mail to "freebsd-wireless-unsubscr...@freebsd.org"

Reply via email to