This repository contains a .NET implementation for computing CRC (Cyclic Redundancy Check) values. This repo includes the library implementation and associated unit tests.
The library can be used to compute a CRC value using a Crc instance that is configured with a CrcParameters object. The CrcParameters class contains properties for width, polynomial, initial value, XOR out value, reflect in and reflect out settings.
byte[] data = System.Text.ASCIIEncoding.ASCII.GetBytes("123456789"); // sample data
var crc32 = new Crc(new CrcParameters(32, 0x04c11db7, 0xffffffff, 0xffffffff, true, true)); // Standard CRC-32 configuration
ulong checkValue = crc32.CalculateAsNumeric(data); //0xcbf43926
byte[] checkValArray = crc32.CalculateCheckValue(data); // [0x26, 0x39, 0xf4, 0xcb]| Family | Count | Models |
|---|---|---|
| CRC-3 | 2 | GSM, ROHC |
| CRC-4 | 2 | G-704, Interlaken |
| CRC-5 | 3 | EPC-C1G2, G-704, USB |
| CRC-6 | 5 | CDMA2000-A, CDMA2000-B, DARC, G-704, GSM |
| CRC-7 | 3 | MMC, ROHC, UMTS |
| CRC-8 | 20 | AUTOSAR, CDMA2000, DARC, DVB-S2, EBU, I-CODE, ITU, GSM-A, GSM-B, ROHC, OpenSAFETY, J1850, LTE, Maxim, SMBus, WCDMA, BLUETOOTH, HITAG, MIFARE-MAD, NRSC-5 |
| CRC-10 | 3 | ATM, CDMA2000, GSM |
| CRC-11 | 2 | FlexRay, UMTS |
| CRC-12 | 4 | CDMA2000, UMTS, DECT, GSM |
| CRC-13 | 1 | BBC |
| CRC-14 | 2 | GSM, DARC |
| CRC-15 | 2 | CAN, MPT1327 |
| CRC-16 | 31 | ARC, AUG-CCITT, UMTS, CCITT-FALSE, CDMA2000, CMS, DDS-110, DECT-R, DECT-X, DNP, EN-13757, GENIBUS, LJ1200, Maxim, MCRF4XX, OpenSAFETY-A, OpenSAFETY-B, PROFIBUS, Riello, T10-DIF, TMS37157, Teledisk, ISO-IEC-14443-3-A, USB, KERMIT, Modbus, IBM-SDLC, XMODEM, GSM, M17, NRSC-5 |
| CRC-17 | 1 | CAN-FD |
| CRC-21 | 1 | CAN-FD |
| CRC-24 | 8 | OpenPGP, BLE, FlexRay-A, FlexRay-B, Interlaken, LTE-A, LTE-B, OS-9 |
| CRC-30 | 1 | CDMA |
| CRC-31 | 1 | Philips |
| CRC-32 | 12 | ISO-HDLC, AUTOSAR, bzip2, ISCSI, BASE91-D, MPEG-2, cksum, AIXM, JAMCRC, XFER, CD-ROM-EDC, MEF |
| CRC-40 | 1 | GSM |
| CRC-64 | 5 | ECMA-182, Go ISO, WE, XZ, MS |
| Total | 110 |
This library would not have been possible had it not been for Ross Williams’ A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS. I learned so much from the guide and the parameterization model defined within was a huge help. The CRC RevEng project’s ‘Catalogue of parametrised CRC algorithms’ which is maintained by Greg Cook was the source of information for the unit tests. In addition, the answers provided by Mark Adler on various Stack Overflow questions were a huge help in general, but especially on how to calculate CRCs that are under 8 bits in length and how to handle the scenario when ReflectIn != ReflectOut.