Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

CardSaysMoops · 2010-03-08 17:13:01

I am using the windows binary package Winter 2010, all the firmware flashed to those versions, and the client from that too. I was able to decode a 125KHz card that is just like in this article:
http://code.google.com/p/proxmark3/wiki/TagOps
And all the traces looked the same as in the article, and I was able to correlate the number on the card with the stuff I decoded - woot!

However, I then decided to further explore the commands available in the Help system, to see what they all did. At some point the traces STOPPED looking like the article... So I did a device reset, and still, the same commands with the same card no longer produce any meaningful output! I still get a significant tune voltage drop when the card is on the antenna, but the data plot output is not all nice like it used to be. Sadly I didn't save the trace when it was nice, but it really looked exactly like this, from that tutorial:
Good looking trace

Now here's what it looks like, it varies between these two patterns. I've included trace files:

http://www.mediafire.com/file/yezng25tjzy/%20badtrace Trace file 1

http://www.mediafire.com/file/mit3j42ykjw/%20badtrace2 Trace file 2

Any suggestions on getting that nice mode back?
Thank you
CSM

d18c7db · 2010-03-09 00:52:56

I have had similar issues in the past with the proxmark board, I don't think it's software related. The way I dealt with it was to remove power from the board for a few minutes then power up again. I thought it was something weird with my board but is seems you have the issue too... maybe if it happens again I will debug the hardware properly to see what the issue is.

CardSaysMoops · 2010-03-10 16:56:08

Thank you for replying, I will indeed try again a few times and see how it pans out. Will post results here.
Thanks,
CSM

CardSaysMoops · 2010-03-17 01:20:41

Hmm. I keep getting this a strange glitch at the beginning, causing a no-signal capture of "32000" onscreen samples, then some of what appears to be some sort of signal, but it's not recognizable. The signal appears to repeat, so you can see two distinct repeat sections in the hash at the end.
Here's an examples of what I'm getting when I use the command:
data samples 16000

This is the glitch at the beginning:

And this is a closer look at what appears to be data:

These are all from the same capture.

Any thoughts on what that glitch is? I didn't get that when I got good quality captures. It seems to be causing a large delay before any data is captured, and I just get the glitch and flatline unless I use more than 8000 for the data samples command.

As a side note, what's the difference between the onscreen scale used by ltrim command and the samples captured by the data samples #### command?
Thanks,
CSM

Last edited by CardSaysMoops (2010-03-17 01:56:13)

d18c7db · 2010-03-17 01:34:03

Are you doing a "lf read" before the "data samples" ?!?! .... you still need to actually _read_ the tag with lf read.

CardSaysMoops · 2010-03-17 01:58:43

Ahh. Most enlightened answer. You hit the nail on the head! That's what I get for trying to explore the new firmware based solely on the help commands! So many things had changed syntax that I had somehow assumed that was included in the data samples command.
THank you d18c7db!

d18c7db · 2010-03-17 10:19:16

What you are calling a glitch is in fact a plot of the antenna voltage as the frequency is swept over a range. The peak shows you where the antenna resonates best ie optimal frequency.

edo512 · 2010-03-17 14:13:57

Maybe what we need is a big update of the reference manual to reflect the latest changes in the commands? I have been working on other things than the Proxmark for a while, but I need to use it again, so I will do my best to 1st update it to the "winter '10" release, and then update the ref manual. Contributors are welcome!

While I'm at it: does the bootloader need to be updated on this winter '10 release, or is the bootloader from the Summer '09 release sufficient?

Ed

CardSaysMoops · 2010-03-17 21:17:17

When I updated my Proxmark3 from proxmark3.com, I had to update the bootloader as well, the flasher.exe kept giving warning that the bootloader didn't understand some command.

CardSaysMoops · 2010-03-17 21:18:40

d18c7db, I see, I frequently ran the tune command to check things, so the data samples I was plotting were those captured by the tune command sequence!
That's quite interesting.

d18c7db · 2010-03-17 23:50:14

It's not possible for the tune command to capture any samples and store them in the buffer !!11!1
Most likely your buffer contained either junk or old sample data from a much earlier lf read command.

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#1 2010-03-08 17:13:01

Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#2 2010-03-09 00:52:56

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#3 2010-03-10 16:56:08

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#4 2010-03-17 01:20:41

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#5 2010-03-17 01:34:03

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#6 2010-03-17 01:58:43

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#7 2010-03-17 10:19:16

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#8 2010-03-17 14:13:57

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#9 2010-03-17 21:17:17

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#10 2010-03-17 21:18:40

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

#11 2010-03-17 23:50:14

Re: Was decoding wonderfully, but now isn't?? (Windows binary Winter 2010)

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