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Questions tagged [crc]

Cyclic redundancy check. An error checking mechanism used for verifying data integrity in serial protocols.

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CRC checking done automatically on Tcp/Ip?

I wonder, while sending data with TcpClient, is there any sort of CRC checking algorithm that works automatically? Or I have to implement my own algorithm and resend the data if it doesn't arrive to remote host correctly?
unnamed
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Calculating FCS(CRC) for HDLC frame

I have the following frame: 7e 01 00 00 01 00 18 ef 00 00 00 b5 20 c1 05 10 02 71 2e 1a c2 05 10 01 71 00 6e 87 02 00 01 42 71 2e 1a 01 96 27 be 27 54 17 3d b9 93 ac 7e If I understand correctly, then it is this portion of the frame on…
Baz
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Message parity check

Can someone help me out with implementing this sequence of calculations in C#?
redfrogsbinary
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Understanding Cyclic Redundancy Code algorithm for beginners

at section 5.5 of the PNG Specification, it discusses this concept in the PNG file format called "CRC" or "Cyclic Redundancy Code". I've never heard of it before, so I'm trying to understand it. The CRC polynomial employed is x32 + x26 + x23 + x22…
B''H Bi'ezras -- Boruch Hashem
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Why LevelDB and RocksDB need a `masked CRC32`

From the crc32.h of leveldb or rocksdb, we can find a comment saying: static const uint32_t kMaskDelta = 0xa282ead8ul; // Return a masked representation of crc. // // Motivation: it is problematic to compute the CRC of a string that // contains…
Myrfy
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Most efficent way to calculate CRC64 with reflected input

I need to calculate a CRC-64 using this setup into this wonderful website: http://www.sunshine2k.de/coding/javascript/crc/crc_js.html As you can see I require "input reflected" and that means that I need to reverse the bit order of any byte (a bit…
3R_LikeNoOther
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How likely are two blocks of data likely to produce the same CRC64 value?

I have an caching application that uses a CRC64 value to ensure data integrity. I'm thinking about putting an extra field, a timestamp to be passed around with the data between the various cache servers and compared to see if data has…
hookenz
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CRC-CCITT (0xFFFF) function?

Can someone help me with Delphi implementation of CRC-CCITT (0xFFFF)? Already get the Java version, but confusing on how to port it to Delphi public static int CRC16CCITT(byte[] bytes) { int crc = 0xFFFF; // initial value int…
Dels
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How to avoid generation meta files (.crc files) in Spark for text files?

I writing an RDD to the local file system in text format by using the saveAsTextFile method. In the output directory, there is one .crc file for each part file even for the _SUCCESS file. I am just looking for any inbuilt functionality or property…
Vikash Pareek
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How to calculate CRC using this code?

I'm trying to get going radio communication between a device and my server. Data from the device looks like this: fa-00-01-09-16-aa-00-14-10-01-01-00-01-16-ff-ff-ff-ff-ff-ff-cb-14 where last two bytes are CRC. Now I need to send reply to my device…
muliku
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Determining CRC algorithm from data + CRC - embedded application.

I have a set of data protected by 16bit checksums that I need to correct. The checksum locations are known, the exact areas they are calculated on and the exact algorithm used to calculate them are not. 16bit, LSB first. I suspect it's some sort…
mattbarn
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Checking the error detection capabilities of CRC polynomials

I tried to find out how to calculate the error detection capabilities of arbitrary CRC polynomials. I know that there are various error detection capabilities that may (or may not) apply to an arbitrary polynomial: Detection of a single bit…
Silicomancer
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Will renaming a file change its CRC?

As stated, will renaming a file change the CRC? I've checked in plain text files and it didn't. Does this apply to all files of all formats?
Jonn
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E/libEGL: cache file failed CRC check

In my application there is MainActivity contains many buttons clicking on which another activity is created with the image. Click on the image is a simple animation zoom. And there is a problem: two images of all at the frequent click crash activity…
MikaAll
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Distribution of CRC checksums

I am investigating about the collision propability of CRC checksums when they are used as a hashes. I know how to calculate the collision propability for hash algorithms that are evenly distributed (which means the chance to get all possible…
Silicomancer
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