Class: Digest::CRC5
Overview
Implements the CRC5 algorithm.
Constant Summary collapse
- WIDTH =
5
- INIT_CRC =
0x1f
- XOR_MASK =
0x1f
- CRC_MASK =
(0x1f << 3)
- TABLE =
Generated by
./pycrc.py --algorithm=table-driven --model=crc-5 --generate=c
[ 0x00, 0x70, 0xe0, 0x90, 0x88, 0xf8, 0x68, 0x18, 0x58, 0x28, 0xb8, 0xc8, 0xd0, 0xa0, 0x30, 0x40, 0xb0, 0xc0, 0x50, 0x20, 0x38, 0x48, 0xd8, 0xa8, 0xe8, 0x98, 0x08, 0x78, 0x60, 0x10, 0x80, 0xf0, 0x28, 0x58, 0xc8, 0xb8, 0xa0, 0xd0, 0x40, 0x30, 0x70, 0x00, 0x90, 0xe0, 0xf8, 0x88, 0x18, 0x68, 0x98, 0xe8, 0x78, 0x08, 0x10, 0x60, 0xf0, 0x80, 0xc0, 0xb0, 0x20, 0x50, 0x48, 0x38, 0xa8, 0xd8, 0x50, 0x20, 0xb0, 0xc0, 0xd8, 0xa8, 0x38, 0x48, 0x08, 0x78, 0xe8, 0x98, 0x80, 0xf0, 0x60, 0x10, 0xe0, 0x90, 0x00, 0x70, 0x68, 0x18, 0x88, 0xf8, 0xb8, 0xc8, 0x58, 0x28, 0x30, 0x40, 0xd0, 0xa0, 0x78, 0x08, 0x98, 0xe8, 0xf0, 0x80, 0x10, 0x60, 0x20, 0x50, 0xc0, 0xb0, 0xa8, 0xd8, 0x48, 0x38, 0xc8, 0xb8, 0x28, 0x58, 0x40, 0x30, 0xa0, 0xd0, 0x90, 0xe0, 0x70, 0x00, 0x18, 0x68, 0xf8, 0x88, 0xa0, 0xd0, 0x40, 0x30, 0x28, 0x58, 0xc8, 0xb8, 0xf8, 0x88, 0x18, 0x68, 0x70, 0x00, 0x90, 0xe0, 0x10, 0x60, 0xf0, 0x80, 0x98, 0xe8, 0x78, 0x08, 0x48, 0x38, 0xa8, 0xd8, 0xc0, 0xb0, 0x20, 0x50, 0x88, 0xf8, 0x68, 0x18, 0x00, 0x70, 0xe0, 0x90, 0xd0, 0xa0, 0x30, 0x40, 0x58, 0x28, 0xb8, 0xc8, 0x38, 0x48, 0xd8, 0xa8, 0xb0, 0xc0, 0x50, 0x20, 0x60, 0x10, 0x80, 0xf0, 0xe8, 0x98, 0x08, 0x78, 0xf0, 0x80, 0x10, 0x60, 0x78, 0x08, 0x98, 0xe8, 0xa8, 0xd8, 0x48, 0x38, 0x20, 0x50, 0xc0, 0xb0, 0x40, 0x30, 0xa0, 0xd0, 0xc8, 0xb8, 0x28, 0x58, 0x18, 0x68, 0xf8, 0x88, 0x90, 0xe0, 0x70, 0x00, 0xd8, 0xa8, 0x38, 0x48, 0x50, 0x20, 0xb0, 0xc0, 0x80, 0xf0, 0x60, 0x10, 0x08, 0x78, 0xe8, 0x98, 0x68, 0x18, 0x88, 0xf8, 0xe0, 0x90, 0x00, 0x70, 0x30, 0x40, 0xd0, 0xa0, 0xb8, 0xc8, 0x58, 0x28 ].freeze
Instance Method Summary collapse
-
#initialize ⇒ CRC5
constructor
Initializes the CRC5 instance.
-
#update(data) ⇒ Object
Updates the CRC5 checksum.
Methods inherited from CRC
#<<, #block_length, checksum, #checksum, #digest_length, #finish, pack, #reset
Constructor Details
#initialize ⇒ CRC5
Initializes the CRC5 instance.
40 41 42 43 44 |
# File 'lib/digest/crc5.rb', line 40 def initialize @crc_mask = self.class.const_get(:CRC_MASK) super end |
Instance Method Details
#update(data) ⇒ Object
Updates the CRC5 checksum.
52 53 54 55 56 57 58 |
# File 'lib/digest/crc5.rb', line 52 def update(data) data.each_byte do |b| @crc = ((@table[((@crc >> 3) ^ b) & 0xff] ^ (@crc >> 8)) & @crc_mask) end return self end |