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MemberMarch 9, 2020 at 12:27 pm
the problem of using A pins as input is, that inside the CONTROLLINO there are used pull-downs in this input to handle the 12V/24V input voltage on analog inputs at screw terminal. So you shall not use for example internal pull-ups, but try to connected the keayboard to the Dx pins where are not puldowns.
You shall be also carefull, that Dx pins on the pinheader are somehow in parallel to crew terminal outputs, so via via logic 1 on the screw terminal you are switching also the corresponding output. Here you shall double check the configuration of the processor that you are not going against for example log. LOW.
About the I2C there can be problem with too high pull-ups and higher capacitance connected on the bus. Please check via oscilloscope the slopes and tune it regarding the results.