# frozen_string_literal: true # turn byte array into hex string def str_hex(data) data.unpack1('H*').scan(/../).join(' ').upcase end # turn hex string to byte array def str_bytes(str) str.scan(/../).map { |b| b.to_i(16) } end def bytes_to_str(data) data.unpack('H*').join end def get_byte(data, start = 0, num = 1) data[start...(start + num)].unpack('H*').join.upcase end