Android Question CRC-16

[sseaand]

Please help to wrap this code to B4A

 

[OliverA]

https://www.b4x.com/android/forum/threads/crc-16-arc.90616/
https://www.b4x.com/android/forum/threads/modbus-crc16-calculation.39825/#post-374443
https://www.b4x.com/android/forum/threads/modbus-crc16-calculation.39825/#post-374827

Corrected links...

 

[DonManfred]

Maybe this is what you are searching?

 

[sseaand]

Sub Process_Globals
  Private NativeMe As JavaObject
End Sub

Sub Globals
End Sub

Sub Activity_Create(FirstTime As Boolean)
  'Do not forget to load the layout file created with the visual designer. For example:
  If FirstTime Then
    NativeMe.InitializeContext
  End If

  Dim Result As String = NativeMe.RunMethod("crc16", Array("16", "5354415445"))
  Log(Result)
End Sub

#If JAVA
      int[] table = { 0x0000, 0x1021, 0x2042, 0x3063, 0x4084,
      0x50A5, 0x60C6, 0x70E7, 0x8108, 0x9129, 0xA14A, 0xB16B, 0xC18C,
      0xD1AD, 0xE1CE, 0xF1EF, 0x1231, 0x0210, 0x3273, 0x2252, 0x52B5,
      0x4294, 0x72F7, 0x62D6, 0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD,
      0xC39C, 0xF3FF, 0xE3DE, 0x2462, 0x3443, 0x0420, 0x1401, 0x64E6,
      0x74C7, 0x44A4, 0x5485, 0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE,
      0xF5CF, 0xC5AC, 0xD58D, 0x3653, 0x2672, 0x1611, 0x0630, 0x76D7,
      0x66F6, 0x5695, 0x46B4, 0xB75B, 0xA77A, 0x9719, 0x8738, 0xF7DF,
      0xE7FE, 0xD79D, 0xC7BC, 0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840,
      0x1861, 0x2802, 0x3823, 0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948,
      0x9969, 0xA90A, 0xB92B, 0x5AF5, 0x4AD4, 0x7AB7, 0x6A96, 0x1A71,
      0x0A50, 0x3A33, 0x2A12, 0xDBFD, 0xCBDC, 0xFBBF, 0xEB9E, 0x9B79,
      0x8B58, 0xBB3B, 0xAB1A, 0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22,
      0x3C03, 0x0C60, 0x1C41, 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD, 0xAD2A,
      0xBD0B, 0x8D68, 0x9D49, 0x7E97, 0x6EB6, 0x5ED5, 0x4EF4, 0x3E13,
      0x2E32, 0x1E51, 0x0E70, 0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B,
      0xAF3A, 0x9F59, 0x8F78, 0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C,
      0xC12D, 0xF14E, 0xE16F, 0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004,
      0x4025, 0x7046, 0x6067, 0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D,
      0xD31C, 0xE37F, 0xF35E, 0x02B1, 0x1290, 0x22F3, 0x32D2, 0x4235,
      0x5214, 0x6277, 0x7256, 0xB5EA, 0xA5CB, 0x95A8, 0x8589, 0xF56E,
      0xE54F, 0xD52C, 0xC50D, 0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466,
      0x6447, 0x5424, 0x4405, 0xA7DB, 0xB7FA, 0x8799, 0x97B8, 0xE75F,
      0xF77E, 0xC71D, 0xD73C, 0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657,
      0x7676, 0x4615, 0x5634, 0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8,
      0x89E9, 0xB98A, 0xA9AB, 0x5844, 0x4865, 0x7806, 0x6827, 0x18C0,
      0x08E1, 0x3882, 0x28A3, 0xCB7D, 0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9,
      0x9BD8, 0xABBB, 0xBB9A, 0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1,
      0x1AD0, 0x2AB3, 0x3A92, 0xFD2E, 0xED0F, 0xDD6C, 0xCD4D, 0xBDAA,
      0xAD8B, 0x9DE8, 0x8DC9, 0x7C26, 0x6C07, 0x5C64, 0x4C45, 0x3CA2,
      0x2C83, 0x1CE0, 0x0CC1, 0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B,
      0xBFBA, 0x8FD9, 0x9FF8, 0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93,
      0x3EB2, 0x0ED1, 0x1EF0 };

    public String crc16(int crc, String data) {
      int result = (crc « 8) ^ table[((crc » 8) ^ data) & 0xFF];
      return (result & 0xFFFF);
}
#End If

this example doesn't work, my attempt too

 

[OliverA]

this example doesn't work, my attempt too

It is hard to help out when logs/error messages or whatever output that shows it does not work is not given.

 

[sseaand]

[CODE]B4A Version: 8.00
Parsing code.    (0.00s)
Compiling code.    (0.03s)
Compiling layouts code.    (0.00s)
Organizing libraries.    (0.00s)
Generating R file.    (0.34s)
Compiling generated Java code.    Error
javac 1.8.0_131
src\b4a\example\main.java:411: error: bad operand types for binary operator '^'
      int result = (crc « 8) ^ table[((crc » 8) ^ data) & 0xFF];
                                                  ^
  first type:  int
  second type: String
Note: src\b4a\example\starter.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
1 error

 

[OliverA]

Where did this code come from? Neither I nor @DonManfred linked to that code.

 

[sseaand]

gave the device manufacturer

 

[OliverA]

Well, the java code is wrong. It needs to convert the string to bytes. Why are you not checking out the code @DonManfred posted (same as my #1 post)?

 

[sseaand]

example from your post doesn't work

B4A Version: 8.00
Parsing code.    (0.00s)
Compiling code.    (0.04s)
Compiling layouts code.    (0.00s)
Organizing libraries.    (0.01s)
Generating R file.    (0.41s)
Compiling generated Java code.    Error
javac 1.8.0_131
src\b4a\example\main.java:422: error: class, interface, or enum expected
}
^
1 error

 

[OliverA]

src\b4a\example\main.java:422: error: class, interface, or enum expected
}
^
1 error

Take out the last } in the Java code (the one before #end if).