Hello everyone, I need a function that can calculate CRC-8, but this is difficult for me, the C algorithm reference is as follows: unsigned char CRC8_Check(unsigned char *ptr,unsigned char len) { unsigned char crc; unsigned char i; unsigned char j; crc = 0; if(len>2) …

Here is a function version... const CRC8_LOOKUP = [ 0x00, 0x07, 0x0e, 0x09, 0x1c, 0x1b, 0x12, 0x15, 0x38, 0x3f, 0x36, 0x31, 0x24, 0x23, 0x2a, 0x2d, 0x70, 0x77, 0x7e, 0x79, 0x6c, 0x6b, 0x62, 0x65, 0x48, 0x4f, 0x46, 0x41, 0x54, 0x53, 0x5a, 0x5d, 0xe0, 0xe7, 0xee, 0xe9, 0xfc, 0xfb, 0xf2, 0…

You can try to search google "Javascript crc-8 function" then implement it using the function node

Thank you very much for your reply, I have tested your node, but it is not the CRC8 checksum result I want, that's why I am posting for help. For example, I want to calculate the string: 7e79030f010002020000000001 with CRC8 checksum result: 0x91, but your node calculates it as: 0xbe, now I don't kno…

If you are using later version of node-red, you can use the easy-crc package. If not, let me know and I'll give you a pure node-red function node with lookup table. using easy-crc in a function... [image] [{"id":"e2beeb574d982801","type":"inject","z":"3b62e67b4dfcce5d","name":"7e79030f0100020200…

steve, thanks a lot for your help! Could you please give me a node-red function node, because I won't install npm packages outside of node-red. :sweat_smile:

[image] Angin: Could you please give me a node-red function node This is a pure node-red function (apart from the import easy-css) [image] Angin: because I won't install npm packages outside of node-red. This solution does use an npm package (easy-crc) but you dont have to manually in…

Yes, I don't have access to install npm packages. [Clipboard 3] The above node is not working for me. [Clipboard 4]

steve, thank you so, so much! Solved a big problem for me! This forum is so honored to have you!

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CRC-8 checksum function

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Steve-Mcl 3 January 2023 07:16 3

Also search this forum. E.g. Help on CRC-8 function - #9 by Steve-Mcl

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CRC-8 checksum function

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