Committing initial intro work

.gitignore

@@ -182,6 +182,7 @@ cython_debug/
 *.su
 *.idb
 *.pdb
+.idea
 
 # Kernel Module Compile Results
 *.mod*

bluetooth/README.md

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+# Bluetooth 
+
+This section contains code or examples in interacting with Bluetooth from the Mac.
+
+## Library
+
+This code is primarily built using [Pybluez](https://github.com/pybluez/pybluez).

python_binary/README.md

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+# Learning binary with Python
+
+This section is targeted towards the interaction with binary data from Python.
+
+## Resources
+
+- https://pymotw.com/2/struct/

python_binary/binary_utils.py

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+"""
+Contains various helper functions for dealing with binary or hex values in Python.
+"""
+
+
+def get_bin(value, padn=0, sep=None):
+    """Prints a binary textual representation of a value"""
+    return format(value, 'b').zfill(padn)

python_binary/intro_bytes.py

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+"""
+Module explores the builtins functions for working with some binary data.
+"""
+import sys
+
+print("This device's native byteorder is: {}\n".format(sys.byteorder))
+
+# One word (16 bit) Hex number
+dead_hex = 0xDEAD  # 57005
+beef_hex = 0xBEEF
+print("hex: {} int: {} bin: {} bitlength: {}\n".format(hex(dead_hex), dead_hex, bin(dead_hex), dead_hex.bit_length()))
+
+# Binary numbers
+
+deadbeef_bin = 0xDEADBEEF
+
+print("int.bin_to_bytes type        : {}".format(type(deadbeef_bin.to_bytes(4, byteorder="big")))) # immutable type
+print("0xDEADBEEF big endian bin    : {}".format(deadbeef_bin.to_bytes(4, byteorder="big")))
+print("0xDEADBEEF little endian bin : {}".format(deadbeef_bin.to_bytes(4, byteorder="little")))
+
+print("0xDEADBEEF in native endian  : {}".format(deadbeef_bin.to_bytes(4, byteorder=sys.byteorder)))
+
+# Error checking in to bytes
+try:
+    deadbeef_bin.to_bytes(1, byteorder=sys.byteorder)
+except OverflowError:
+    print("Caught an overflow error when too few bytes were attempted to represent a 32bit value")
+
+print("Sign matters. Signed binary values use 2's complement.")
+value = 0b11111111 # 255 unsigned -1 when signed
+bytes_value = value.to_bytes(1, byteorder=sys.byteorder)
+print("Unsigned value: {}".format(int.from_bytes(bytes_value, byteorder=sys.byteorder, signed=False)))
+print("signed value: {}".format(int.from_bytes(bytes_value, byteorder=sys.byteorder, signed=True)))
+
+
+## Binascii
+
+# As it says in the standard lib docs this package is for converting binary/ascii
+

python_binary/struct_intro.py

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+import struct
+import binascii
+
+
+def get_bin(value, padn=0, sep=None):
+    """Prints a binary textual representation of a value in """
+    return format(value, 'b').zfill(padn)
+
+
+# Packing a data structure
+
+values = (1, b'ab', 2.7)
+s = struct.Struct('I 2s f')
+packed_data = s.pack(*values)
+
+print("\n##### Struct Packing Example #####\n\n")
+print('Original values      :', values)
+print('Packed Type          :', type(packed_data))
+# This is most likely going to contain non ascii characters when printed.
+# So it's not suitable to copy it over the printed string and then try to
+# hexlify
+print('Packed print         :', packed_data)
+print('Format string        :', s.format)
+print('Uses                 :', s.size, 'bytes')
+print('Packed Value (hex)   :', binascii.hexlify(packed_data))
+# binascii.hexlify(data[, sep[, bytes_per_sep=1]]) can also make more
+# human readable values
+print('Spaced Value (hex)   :', binascii.hexlify(packed_data, b"_", 4))
+
+# Unpacking a data structure
+
+packed_data = binascii.unhexlify('0100000061620000cdcc2c40')
+
+unpacked_data = s.unpack(packed_data)
+
+print("\n##### Struct Unpacking Example #####\n\n")
+print('Unpacked Values:', unpacked_data)
+
+# Endianness in binary data
+
+print("\n##### Endianness Demonstration #####\n\n")
+print('Original values:', values)
+
+endianness = [
+    ('@', 'native, native'),
+    ('=', 'native, standard'),
+    ('<', 'little-endian'),
+    ('>', 'big-endian'),
+    ('!', 'network'),
+]
+
+for code, name in endianness:
+    s = struct.Struct(code + ' I 2s f')
+    packed_data = s.pack(*values)
+
+    print('Format string  :', s.format, 'for', name)
+    print('Uses           :', s.size, 'bytes')
+    print('Packed Value   :', binascii.hexlify(packed_data))
+    print('Unpacked Value :', s.unpack(packed_data), "\n")