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#1 2019-06-24 00:15:51

mwalker
Contributor
Registered: 2019-05-11
Posts: 198

lf sim questions

Just to check I have this right.

lf sim will simply send out/playback the data in the buffer as captured.
So (in theory and given everything going well) if i was to perform an lf snoop (capture a reader request), then perform an lf sim with a card on the pm3, the card would see the "original" packet from the reader.

1. Does the play back consider the config d (decimation) of the data in the buffer when clocking back ?

e.g. If perform the following.
lf config t 64 d 2
lf snoop
(at this point 1 in 2 samples are in the buffer)
lf sim

Does this play back each sample twice(holdx2), or will it play back twice as fast ?

2. Do any other options affect the playback, such that if I change this at snoop time, should i ensure they are the same at sim time.

What I am about to play with is take a capture, slice up into separate packets/blocks then play back one at a time to see which one makes the changes.

thanks

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#2 2019-07-06 13:58:32

marshmellow
Moderator
From: US
Registered: 2013-06-10
Posts: 2,299

Re: lf sim questions

Afaik, lf sim does not currently know about decimation or any other lf config options.  Good suggestion though!

It is also important to note that ultimately to simulate a wave with the pm3 you need binary, so inside the lf sim is a simple wave decoder that puts the wave into binary.  This can create an inaccurate decoding if you're waveform is weak or has noise in it.

You should clean you're waveforms first and then attempt the lf sim
Using one of the data cmds that works best for you're wave.

Last edited by marshmellow (2019-07-06 13:59:56)

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