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After making someone's day on the NI forums last fall for yet another CRC variation, I decided to go look for a fully-implemented LabVIEW reuse library I could just link to for the next such request. I really couldn't find one. Hence, the attached. It's intended to be a user.lib reuse library (although the attached zip includes a small demo project with a test VI). There's really only about two genuine VIs in the library, both are malleable to adapt to the poly/init integer sizes. One is the CRC computation VIM and the other is a lookup table builder; you have the option of pay-as-you-go (eight shifts/tests and conditional XORs, aka "brute force"), or you can take the computational hit upfront once and build a lookup table. Outputs are tested correct for the lengthy list of "well-known" CRCs (included in the library as some handy typedef'd cluster constants), when tested against some reputable online calculators. What is NOT done: I haven't made any serious attempts at benchmarking performance, brute force vs. lookup table. I'd be happy to have the LAVA community beat this up and suggest improvements in: speed, code elegance, style, whatever. Dave CRC.zip