Solved: Re: CRC 32bit

jay0909 · ‎07-18-2016

Hi,

i am communicating with stm 32 via UART. The frame i receive is "1C000000B0B80700040400000000000000" and the CRC of the frame is " 9D0351B5". its not matching the calculation of the crc which i do, the calcuated crc is " 226F9471" . I tried the calculation with python and other sources calculated crc works fine. If anyone how to solve, pleas elet me know.

crossrulz · ‎07-18-2016

Any clue about the code the microcontroller is running? There are many variations on CRCs, so you pretty much need to know what algorithm is being used in order to get it to work.

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Norbert_B · ‎07-18-2016

Also things like high byte/low byte ordering are important which could "swap" by communication protocols.

Norbert

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jay0909 · ‎07-18-2016

nope. I don't know that info. but i know the CRC calculation is according to the IEEE 802.3 standard. Also Communication is Little Endian.

Norbert_B · ‎07-18-2016

@jay0909 wrote:

[...] Also Communication is Little Endian.

Are you sending the data litle endian?

Norbert

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jay0909 · ‎07-18-2016

Hi

Nope I recieve in Little Endian, as per the UART specs. I cannot send becos of the CRC problem.

Norbert_B · ‎07-18-2016

Can you post your VI which includes the receiver part?

Norbert

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billko · ‎07-18-2016

I believe there is a nice set of CRC vis in the VIPM.

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PalanivelThiruvenkadam · ‎07-18-2016

If it's works fine in python it should also work in LabVIEW.
Check with the way it's implemented in python and in LabVIEW and find the difference
Basic CRC is add all the data other than header .

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Palanivel Thiruvenkadam | பழனிவேல் திருவெங்கடம்
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jay0909 · ‎07-19-2016

Hi,

The attachment contains the code of the recieving end. I have segregated according to the frame format last 4 bytes after data is the CRC.

@ PalanivelT : Please read the whole post carefully.