CRC check value and “123456789”
Every CRC model publishes a check value for ASCII '123456789' — use it to verify width, polynomial, Init, reflection, and XorOut before trusting real data.
Why 123456789 is used
CRC catalogues conventionally publish the result for the ASCII bytes of 123456789. This result is called the check value and provides a compact interoperability test.
31 32 33 34 35 36 37 38 39What a matching check value proves
A matching check value strongly indicates that width, polynomial, Init, RefIn, RefOut, and XorOut are implemented consistently for that model. It does not by itself verify application-specific framing or transmitted byte order.
Recommended validation workflow
Test the check string, compare several known protocol frames, and verify empty input where a reference value is available. Automated tests should run for every preset whenever the engine changes.
Apply this reference
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