+def reverse_number(num, count):
+ out = list(count * '0')
+ for i in range(0, count):
+ if num >> i & 1:
+ out[i] = '1'
+ return int(''.join(out), 2)
+
+def calc_crc5(bitstr):
+ poly5 = 0x25
+ crc5 = 0x1f
+ for bit in bitstr:
+ crc5 <<= 1
+ if int(bit) != (crc5 >> 5):
+ crc5 ^= poly5
+ crc5 &= 0x1f
+ crc5 ^= 0x1f
+ return reverse_number(crc5, 5)
+
+def calc_crc16(bitstr):
+ poly16 = 0x18005
+ crc16 = 0xffff
+ for bit in bitstr:
+ crc16 <<= 1
+ if int(bit) != (crc16 >> 16):
+ crc16 ^= poly16
+ crc16 &= 0xffff
+ crc16 ^= 0xffff
+ return reverse_number(crc16, 16)
+