Converting PySerial Readline From String to Binary

Question

I'm sending the bytestring 0x0F, 0x07, 0x55, 0x55, 0x55 from a PIC microcontroller.

Over the serial port with Python I am using the readlines() command in PySerial. I receive:

['\x0f\x07UUU']

This does indeed correspond to the bytestring I sent, but it is formatted using what looks like a strange combination of hexadecimal and ASCII characters. What would be a good way to format this back to 0x0F, 0x07, 0x55, 0x55, 0x55?

Answer 1

In Python 2, a bytestring (str) is a string of 8-bit characters, so it will look like that. Use the "ord" function convert each character to an int:

>>> [ord(c) for c in '\x0f\x07UUU']
[15, 7, 85, 85, 85]

Answer 2

Check out binascii.hexlify . According to the descritption:

Return the hexadecimal representation of the binary data. Every byte of data is converted into the corresponding 2-digit hex representation. The resulting string is therefore twice as long as the length of data.

An example:

>>> import binascii
>>> binascii.hexlify('\x0f\x07UUU')
'0f07555555'

Answer 3

For back to hex:

>>> data = binascii.hexlify('\x0f\x07UUU')
>>> ['0x' + data[i:i+2] for i in range(0, len(data), 2)]
['0x0f', '0x07', '0x55', '0x55', '0x55']