Hi WebMaka,
thank you for your explanation, I see your point, unfortunately avoiding the numbers of bytes didn't fix the issue but first, via python command, I get a different error:
>>> data = i2c.read_i2c_block_data(0x08,0x90)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
IOError: [Errno 110] Connection timed out
it is now a connection time out and then if I run the command again
>>> data = i2c.read_i2c_block_data(0x08,0x90)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
IOError: [Errno 5] Input/output error
the same error I was getting before.
Regarding the data, I'm transmitting unsigned int and byte values, of course managing low and high bytes for int, the logic is working because the data transmission is working from raspberry pi to arduino, the data are correctly received from the Arduino.