Class: CRC8Stream

• Inheritance
• Description
• Class protocol
  • instance creation
  • queries
• Instance protocol
  • initialization
  • queries
  • writing
• Examples

Inheritance:

   Object
   |
   +--Stream
      |
      +--HashStream
         |
         +--CRCStream
            |
            +--CRC8Stream

Package:

stx:libbasic2

Category:

System-Crypt-Hashing

Version:

rev: 1.5 date: 2023/11/29 15:21:59

user: cg

file: CRC8Stream.st directory: libbasic2

module: stx stc-classLibrary: libbasic2

Description:

newSAE_J1850:
  Standard CRC method as defined by SAE J1850 (used in AUTOSAR)
  The polynomial is 0x1D; initial value 0xFF; xorOut is 0xFF
  

[instance variables:]

[class variables:]

copyright
COPYRIGHT (c) 2019 by eXept Software AG
             All Rights Reserved

This software is furnished under a license and may be used
only in accordance with the terms of that license and with the
inclusion of the above copyright notice.   This software may not
be provided or otherwise made available to, or used by, any
other person.  No title to or ownership of the software is
hereby transferred.

Class protocol:

 generatorPolynomMSB: anInteger

notice, in literature, the generator polynom is usually specified as an MSB number

 generatorPolynomMSB: anInteger initValue: initValue

notice, in literature, the generator polynom is usually specified as an MSB number

 generatorPolynomMSB: anInteger initValue: initValueArg xorOut: xorOut

notice, in literature, the generator polynom is usually specified as an MSB number

 newSAE_J1850

return an instance of the SAE_J1850 CRC8 (used in AUTOSAR)

 new_2F

return an instance of the CRC8-2F (used in AUTOSAR).
Currently broken.

 hashSize

return the size of the hashvalue returned by instances of this class (in bytes)

Instance protocol:

 generatorPolynom: anLSBInteger

set the generator polynom for this instance,
set start and xorOut to 16rFF.
Note: you have to set the bit-reversed value, so the LSB must be first

 generatorPolynom: anLSBInteger initValue: initValueArg

set the generator polynom for this instance.
set start to initValueArg and xorOut to 16rFF.
Note: you have to set the bit-reversed value, so the LSB must be first

 reset

(comment from inherited method)
reset the current crc value

 hashValue

return the computed CRC

 nextPutByte: byte

(comment from inherited method)
add the hash of anObject to the computed hash so far.
aByte can be a SmallInteger <= 255

 nextPutBytes: count from: anObject startingAt: start

(comment from inherited method)
add the hash of anObject to the computed hash so far.

Examples:

    self assert:(CRC8Stream newSAE_J1850 hashValueOf:#[16rF2 16r01 16r83]) = 16r37. 
    = 55