Re: [Openbeacon-openamd] Protocol Specs for 25c3

[Tomasz R. <bog...@po...>]

Dnia 2009-02-19, czw o godzinie 11:26 +0100, Stephan Jennewein pisze:
> Hi,
> 
> I need some information about the openbeacon protocol used on the 25c3.

I have analysed dump generated by USB reader and here
is my interpretation of 16 bytes of frame.

byte(s) - meaning
1 - 0x18
2, 3 - ID of tag
4 - 16 (0x10)
5-  flags, 2 if button pressed, 0 otherwise
6 - strength: 0, 1, 2 (3 is used for tag-tag sensing)
7 ,8 - recent contact ID
9, 10 - unused (other contact?)
11,12,13,14 - sequence number
15, 16 - CRC

> 
> I got the 16 data bytes out of the pcap files, but what is in there and where?
> The old decode code used 18bytes, what is fallen out?
> Then I need to know how many packets a tag sends per second and in which 
> strength to the readers and other tags and how is this stored.

What files do you have and where did you get them?

> 
> Is the old map of the bcc still up to date ? If yes, how do I map the ip 
> addresses of the readers to the numbers on the map?

It is rather up to data - except that during 25C3 there was no reader
in the Heaven (F002 on the map/during 24C3) but one was placed in
corridor leading to Heaven.

I also attach Perl script I used to analyse data dumped by
USB reader - but beware of ugly code. It also does not do anything
except printing some numbers on the screen.
It was used by me to come with description I place
in this mail.

-- 
Tomasz Rybak <bog...@po...> GPG key ID: F22C D870
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