How do I get the first 11 bits of a 32 bit int with ctypes
?
import ctypes
class Fields(ctypes.Structure):
_pack_ = 1
_fields_ = [('a', ctypes.c_uint, 11)]
class BitField(ctypes.Union):
_pack_ = 1
_fields_ = [('b', Fields),
('raw', ctypes.c_uint)]
bf = BitField()
bf.raw = 0b01010000001000000000000000000001
print('0b{:0>32b}'.format(bf.raw))
print('0b{:0>32b}'.format(bf.b.a))
Result:
0b01010000001000000000000000000001
0b00000000000000000000000000000001
Whereas I wanted
0b01010000001000000000000000000001 0b00000000000000000000001010000001
Another option could be to use
class Fields(ctypes.Structure):
_pack_ = 1
_fields_ = [('x', ctypes.c_uint, 21), ('a', ctypes.c_uint, 11)]