Library for 8 X PCF8574A IO-Expander (64Bits)

[AlbertoFS]

This is a library for 8 X IO-Expander PCF8574A (64Bits).
The PCF 8574A is a more unique and hard to make work. I have been able to see that false interrupts are generated when writing to the port (Could be Proteus). This chip has the peculiarity of not having configuration registers and the inputs and outputs are mixed in a single port. Writing can modify reading.
I have written a very safe code that eliminates all spurious interrupt problems. And I got a new code that allows to easily control 8 expanders. You can trust this library.