Hi Michael, Thanks for your fast reply.I've been running in a lot of things, so 
i coudn't answer you back.To the problem: basically then, if the packet 
receives a 0x7D, the code checks if its subsequent byte is 0x5E or 0x5D to 
discover if its a 7E or 7D being transmitted. I still haven't been through the 
"CD00" value below however. Also, somehow and sometimes only, reading through 
the Labview VISA, my packets are not being received correctly. The read packet 
bounces and i get the wrong data.My buffer is set to the default (4096), so i 
think it's not a problem of buffer. Neither the 115200bps baud rate.  I suspect 
XSniffer filters this half-packets off, just to display the right data.Have you 
experienced such a thing? Any ideas to implement flow control?Cheers and 
thanks,Edgar Charry> Date: Thu, 13 Mar 2008 11:31:17 -0600> From: [EMAIL 
PROTECTED]> To: [EMAIL PROTECTED]> CC: [email protected]> 
Subject: Re: [Tinyos-help] Packet structure with TinyOS-1.x> > The mystery 5D 
is actually an "escaped" 7D (hmm or 7E -- I don't remember> which off-hand). 
The trailing 7E's are the "framing" bytes at the end and> beginning of each 
message (thus leading to the need for escaping them> elsewhere) and the last 42 
is radio message type, so your framing is> off a bit. I think the remaining ??? 
values are the CRC and other> internal message structure. See this page for 
excruciating detail:> > 
http://www.octavetech.com/pubs/TB5-01%20Deciphering%20TinyOS%20Serial%20Packets.pdf>
 > MS> > Edgar Charry wrote:> > Hello everyone,> > > > I am experimenting 
problems with the packet structure. I'm using the > > TinyOS1.x operating 
system.> > The TOS_Msg struc is intact, but i've changed the xsensor header a 
bit. > > However i cannot recognized some bytes that my programm is listening > 
> (and shouldn't be received). They are marked with a "???" below. Can > > 
anyone PLEASE give me any sort of explanation? As strenght and ack bytes > > 
are not sent, don't really know what they are (or where the CRC is).> > > > My 
packet struc should be 5 bytes of TinyOS Header :> > a. Dest Add - 2, AM Group 
- 1, AM Type - 1, Length - 1> > > > another 6 bytes of xsensor header (which i 
changed to count the packets > > supposed to be transmitted and the transmitted 
in fact):> > b. packet_id - 2, tx_id - 2, node_id = 1, rsvd -1> > > > and the 
payload that should contain 8 bytes:> > c. thermistor - 2, adc2 - 2, adc3 - 2, 
adc4 - 2.> > > > and:> > d. 2 bytes of crc.> > > > Leading to a total of: 21 
bytes.> > > > However listening to the UART Port using Labview i read 27 bytes 
everytime.> > Below:> > > > FFFF 007D 5D0E A200 A200 0700 DB01 A701 5B02 1702 
CD00 C5B3 7E7E 42:> > > > FFFF: Dest Add |> > 00: AMGroup |> > 7D: AMType|> > 
5D = ????> > 0E: length (which is 14bytes and is correct)|> > A200: packet id|> 
> A200: tx id|> > 07: node id|> > 00: reserved|> > DB01:Thermistor|> > 
A701:ADC2|> > 5B02:ADC3|> > 1702:ADC4|> > CD00:???> > C5B3:???> > 7E7E:???> > 
42:???> > > > Thanks many times for any kind of guidance!> > Edgar Charry> > > 
> ------------------------------------------------------------------------> > 
Express yourself instantly with MSN Messenger! MSN Messenger > > 
<http://clk.atdmt.com/AVE/go/onm00200471ave/direct/01/>> > > > > > 
------------------------------------------------------------------------> > > > 
_______________________________________________> > Tinyos-help mailing list> > 
[email protected]> > 
https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help> > -- 
> Platform: WinXP/Cygwin> TinyOS version: 1.x, Boomerang> Programmer: MIB510> 
Device(s): Mica2, MicaZ, Tmote> Sensor board: homebrew> 

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