crc16

问题 I'm coding a MODBUS CRC16 calculator in C. What I have before is a python that do this, I wanted to convert it to C. I found some codes online but it's not giving me the correct answer. For my python code, I have this as my CRC16.py #!/usr/bin/env python def calc(data): crc_table=[0x0000,0xC0C1,0xC181,0x0140,0xC301,0x03C0,0x0280,0xC241,0xC601,0x06C0,0x0780,0xC741,0x0500,0xC5C1,0xC481,0x0440,0xCC01,0x0CC0,0x0D80,0xCD41,0x0F00,0xCFC1,0xCE81,0x0E40,0x0A00,0xCAC1,0xCB81,0x0B40,0xC901,0x09C0

问题 can anybody share a link or sample code to implement checksum for string in javascript? Thanks a lot in advance 回答1: What do you want? You need to be more specific. There is a huge plethora of CRC16 algorithms, each one with its own polynomial and for a specific use. Some CRC16 algorithms are really good to create hashes ( for Redis, for example ) while others are better for wire communication. https://en.wikipedia.org/wiki/Cyclic_redundancy_check#Polynomial_representations_of_cyclic

问题 can anybody share a link or sample code to implement checksum for string in javascript? Thanks a lot in advance 回答1: What do you want? You need to be more specific. There is a huge plethora of CRC16 algorithms, each one with its own polynomial and for a specific use. Some CRC16 algorithms are really good to create hashes ( for Redis, for example ) while others are better for wire communication. https://en.wikipedia.org/wiki/Cyclic_redundancy_check#Polynomial_representations_of_cyclic

问题 I have two sources to calculate the seemingly same crc value. I can not figure out why the 'boost/crc.hpp' implementation differs from the 'linux/lib/crc-ccitt.c' implementation. crc-ccitt.c boost Here is an example that illustrates the Problem. It is sligthly longer since i do not have the Linux kernel source on my Computer. It compiles if you link boost to it. The Problem is that Linux and boost do not agree on the crc value. The Linux source states that: The polynomial ... 0x8408. Add the

问题 I have the following buffer byte pingBuff[] ={0x01, 0x01,0x00,0x01,0x00,0x20} I need to calculate 16 bit CRC of these 6 bytes and append it at the end of the pingBuff[] I have done it using C++ and tried to change that code in java like below but it didnot work. package org.totalbeginner.tutorial; public class CRCLikeC { /* Table of CRC values for high–order byte */ char auchCRCHi[] = { 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,

问题 I am trying to to calculate CRC-16 from NSData. It is not working, I am expecting "BB3D" from 123456789, but I get nothing like it. This is the code that I have: static const unsigned short crc16table[] = { 0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241, 0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440, 0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40, 0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841, 0xD801, 0x18C0, 0x1980, 0xD941,

问题 I'm trying to add CRC16 error detection to a Motorola HCS08 microcontroller application. My checksums don't match, though. One online CRC calculator provides both the result I see in my PC program and the result I see on the micro. It calls the micro's result "XModem" and the PC's result "Kermit." What is the difference between the way those two ancient protocols specify the use of CRC16? 回答1: you can implement 16 bit IBM, CCITT, XModem, Kermit, and CCITT 1D0F using the same basic code base.

问题 I'm working on a library to provide simple reliable communication over an RS232 or RS485 connection. Part of this code involves using a CRC16 checksum on the data to detect corruption from line noise. I've created a function to calculate a CRC16 checksum, but it doesn't seem to be outputting correct values. The relevant code I've written is below (it can also be found here). #include <stdint.h> #define CRC16 0x8005 uint16_t gen_crc16(const uint8_t *data, uint16_t size) { uint16_t out = 0; int

问题 I can convert string to crc16 but I need convert crc16 to string.Is it possible? function TForm1.CRC_16(Icerik: string): word; var valuehex: word; i: integer; CRC: word; Begin CRC := 0; for i := 1 to length(Icerik) do begin valuehex := ((ord(Icerik[i]) XOR CRC) AND $0F) * $1081; CRC := CRC SHR 4; CRC := CRC XOR valuehex; valuehex := (((ord(Icerik[i]) SHR 4) XOR LO(CRC)) AND $0F); CRC := CRC SHR 4; CRC := CRC XOR (valuehex * $1081); end; CRC_16 := (LO(CRC) SHL 8) OR HI(CRC); end; This function

问题 I am having a lot of trouble on generating a modbus CRC16 code using PHP. I have found a lot of different codes over the internet but i have tried them and for some reason i didnt get right results. I have found a PHP code for generating CRC16-CCITT. I have chenge the look up table to the modbus CRC corresponding table but the result is still not the right one. The code is bellow. What do i need to do more in order to transform a CRC16-CCITT code into CRC16-MODBUS code. <?php /***************