CRC16 calculation in Elixir using constant 0xA001

crc16.ex

defmodule CRC16 do
	use Bitwise	
	@constant 0xA001	

	def calculate(data) do
		crc = 0x0000
		table = init_table()
		:binary.bin_to_list(data)
		|> Enum.reduce(crc, fn(value, crc) ->
			(crc >>> 8) ^^^ Enum.at(table, (crc ^^^ value) &&& 0x00ff)
		end)
	end

	defp init_table() do
		Enum.map(0..255, fn(i) ->
			Enum.reduce(0..7, i, fn(_, crc) ->
				case crc &&& 0x0001 do
					0x0001 -> (crc >>> 1) ^^^ @constant
					_ -> crc >>> 1
				end	
			end)
		end)
	end
end

data = File.read! "filu.bin"
crc = Integer.to_string(CRC16.calculate(data), 16)
IO.puts("CRC is #{crc}")

Hi,

Sorry for the late reply. Github doesn't notify gist's comments so I didn't notice your comment until now.

This should work correctly. I have tested it against other implementations (e.q. https://github.com/cristianav/PyCRC) and it returned same value. Input type is a binary data object. Any normal file or even strings when converted to binary, can be used as an input.