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"Manually" creating RCW for LS1012A - Generating the CRC32

Question asked by hardsoft on Apr 17, 2018
Latest reply on Apr 22, 2018 by Pavel Chubakov

I don't seem to be able to find the right combination of settings to generate the CRC32 checksum for a self-modified RCW. But I have seen posts to this community that suggest this should not be hard. Can someone tell me how to generate the correct CRC32 value using e.g. python or something else?. I looked through the default RCWs in the SDK for LS1012A-FRDM and LS1012A-RDB. They seem, in contrast to what QCVS creates, to follow the recommendation to let the RCW data be directly followed by a CRC check command:

00000000: 0001 ee01 55aa 55aa 0000 0000 0800 0008  ....U.U......... 
00000010: 0000 0000 0000 0000 0c00 00c0 0000 0835  ...............5
00000020: 0018 0000 0000 0040 0000 0000 0000 0000  .......@........
00000030: 7145 0100 0000 0000 20a1 c218 0000 0000  qE...... .......
00000040: 0000 0000 9600 0000 0000 1040 0406 5709  ...........@..W.
00000050: 0000 1050 5c01 5709 0000 0000 0006 5709  ...P\.W.......W.
00000060: 9c00 0000 1804 5709 8028 5000 dc08 ea09  ......W..(P.....
00000070: 204e 1080 0013 ea09 0000 0100 001a ee09   N..............
00000080: 0002 0000 5801 5709 0100 0000 1400 4c89  ....X.W.......L.
00000090: 0c40 0f00 0000 5509 0861 0040 058e c915  .@....U..a.@....

The documentation seems to be rather clear: The CRC includes all bytes before the CRC check command using CRC32 default poly and a start value of 0xffff_ffff. But even with swapping bytes to and fro, I cannot recreate that checksum value. Neither the one following the RCW nor the one at the end.

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