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Shadow Logger data error

Posted: Mon Aug 20, 2012 11:42 pm
by Kristof
Hi,

just wanted to report a little issue with Shadow Logger.
I did a log of about half an hour. One line in the log shows unexpected data.
I shortened the log file to be able to upload it here.
Items used: Shadow Logger V1.17, HTC Desire HD, Rayson BTM222 Bluetooth module.
2012-08-18_18.16.33_err.msl
Regards,
Kristof

Shadow Logger data error

Posted: Tue Aug 21, 2012 1:24 am
by gslender
I get these a fair bit. I just find them in the log and cut them out. Sometimes I also get FRD files that ShadowTuner or TS can't convert due to errors in the stream.

I just assume the data is corrupted as MS2 has no error checking.

G

Re: Shadow Logger data error

Posted: Tue Aug 21, 2012 1:31 am
by Kristof
Ah, forgot to say, I am using MS3 V1.1.0.
There should be CRC checksum, right?

It is also not a problem for me, just wanted to give feedback.

Re: Shadow Logger data error

Posted: Tue Aug 21, 2012 6:31 am
by LT401Vette
Thanks it is good to know if these do pop up.
It would be handy to see the FRD as well if you still have it. as it may even be an error on writing not reading.

Do you know of any activity that might be related, such as using the phone, etc?

There is no crc check on MS2, but there is some rudimentary checking going on and on MS3 it should be passing crc. So if there are bad records making it into an MS3 file, there seems to be something wrong. That is likely related to the MS2 records as well.

Re: Shadow Logger data error

Posted: Tue Aug 21, 2012 6:49 am
by Kristof
Here is the FRD file.
Convertion was made on your server.

I cannot say if it is related to some activities.
But I only switched the display on a few times to take a look at the values.
2012-08-18_18.16.33.zip

Re: Shadow Logger data error

Posted: Tue Aug 21, 2012 10:51 am
by LT401Vette
Interesting... All the data around that blip is valid. However there appears to be an extra 2 byte header, with no data throwing off the offsets for the remaining data. The Transformer is designed to recover from this, and appears to do so, but not until after a record with a 2 byte shift is written to the log.

So, it seems it is in Shadow Logger that it is allowing a header to be written on an empty array for some reason. But the FRD transformer could / should also have a filter to catch the bogus record.

Either way, for this instance, there are 2 fixes, I shall put in both.

Re: Shadow Logger data error

Posted: Tue Aug 21, 2012 12:22 pm
by Kristof
Ok, good to hear that you are able to relate to the problem.