Re: [Discuss-gnuradio] bbn_80211b_rx.py: how is the received packet handled please?

[masond]

Quoting "Y. Zhuang" <address@hidden>:

> Thanks very much for help. So "@qHBB" and "@qHbB" actually mean the
> format that we should unpack this string, right? What is the
> differences between "@qHBB" and "@qHbB" then? and "@BBBBBB"?
>
> Thank you

    Yes. Basically, to summarize the python doc I linked, if you have  
binary data stored in a string you want to decode, each character in  
the python format string corresponds to one or more of the bytes in it  
(with the exception of the @ at the beginning. @ tells the byte order  
and alignment to use -- the system default in this case). Then q would  
be a long long, H an unsigned short, and B being an unsigned char.  
Also, @BBBBBB can be written as @6B, and you can construct the  
formatting strings dynamically if needed (if transmitting a variable  
length packet).

    The difference between qHbB and qHBB is that the lowercase b in  
the middle is signed and the capital B is unsigned. (i.e. is the  
number stored in two's-complement.) Of course, what that means for the  
code is up to the coder.

--Mason