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unsigned char array from int array in python

I try to define a new character (a capital german umlaut "Ä") on my 2004 lcd on a raspberry pi using wiringPi's lcdCharDef()

This is my code

import wiringpi2 as wiringpi
# Ä
cap_umlaut_a = [
 int('0b01010', 2),
 int('0b00100', 2),
 int('0b01010', 2),
 int('0b10001', 2),
 int('0b11111', 2),
 int('0b10001', 2),
 int('0b10001', 2),
 int('0b00000', 2)
]
print(cap_umlaut_a) # [10, 4, 10, 17, 31, 17, 17, 0]
wiringpi.lcdCharDef(lcd_handle, 0, cap_umlaut_a)

When I run this code I get the following error:

TypeError: in method 'lcdCharDef', argument 3 of type 'unsigned char [8]'

I expected these ints to be the same as unsigned chars

[edit]
In a different part of the code I use ord(char) to convert only one character to an unsigned int. Can this lead to the correct anser?

How can I cast/convert the array to a type that can be accepted?

P.S. (Note that (as far as I understand it) the python wiringPi library simply wraps the C functions of wiringPi)

[edit]
I opened an issue on github: https://github.com/WiringPi/WiringPi2-Python/issues/20

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  • Thank you for the answer. I really appreciate that! I just tried it. wiringpi.lcdCharDef(self.lcd_handle, 0, b'\x0A\x04\x0A\x11\x1F\x11\x11\x0') gives an error "ValueError: invalid \x escape" and wiringpi.lcdCharDef(lcd_handle, 0, struct.pack('8B', *cap_umlaut_a)) gives "struct.error: pack requires exactly 8 arguments" Commented Jul 29, 2015 at 23:42
  • 1
    I fixed the first error, but I can't reproduce the second one (with the definitions from your question) Commented Jul 29, 2015 at 23:45
  • hm. thanks for fixing the first one - I've seen it myself now :) now I also get the TypeError here... Maybe there is something else wrong in my code. I will try to make a running minimal example tomorrow and either post it or accept your answer, if I can locate the mistake. Commented Jul 29, 2015 at 23:50
  • ... well, who needs sleep anyway. I just created the minimal example. Still get the same error. You can find it here: gist.github.com/anonymous/0fd82d376cd22763faf1 Commented Jul 29, 2015 at 23:58
  • @speendo, can you try with a normal string instead of a byte string? :< Commented Jul 30, 2015 at 0:24

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