How to change(disable) pin type on the fly from analog to....?

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Anonymous
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Hi Gyus,

Is it possible to disable (currently analog)pins on the fly? Alternatively it would make a difference if i were able to change type of input(from analog to digital output) and change drive mode in order to be able to activate internal pullups.

Background:

As I'm supposed to mux different signals to ADC, different channels are connected to CPU. In the matter of electromagnetic compatibillity I've noticed some bad behaviour(using our EMC setup). My assumption is, that unused channels, which are actually setup as analog input may introduce some electromagnetic sideffects in that time slots they aren't beeing used.

I do not need any suggestions which opportunities there are to handle this type of sideeffects but more strict instructions how to disable unused pins.

I've found an application note how pins and gpios are to be used. There is an example how to make/break connection to analog globals(in order to switch analog/digital input  which shares same GPIO). Is it practicable to do so in my case?

Sharing any other expriences in the matter of EMC will also be appriciated.

Thanks for any hints in advance!

Joe

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Anonymous
Not applicable

"I've found an application note how pins and gpios are to be used. There is an example how to make/break connection to analog globals(in order to switch analog/digital input  which shares same GPIO). Is it practicable to do so in my case?"

My assumption has been wrong, as multiplexer component does exactly the same thing, doesn't it?

Does it make sense to change drive mode to internal pull up in order to make inputs more resistent regarding emc?

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