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Unexpected ADC Behavior Open Channels Displaying ANxx0 Data in nonstop Scan Mode


Issue Description In nonstop mode scan of a 12-bit ADC on a Renesas RA6.

I’ve configured 4 ADC channels ANxx0 to ANxx3. However, I have left ANxx1 to ANxx3 open and provided input to the ANxx0 pin. In this configuration, when I observe the ADC results, ANxx1 to ANxx3 display the count values or scan values of ANxx0, which is unanticipated.

This behavior indicates that ANxx1 to ANxx3 are showing the values of ANxx0 indeed though they’re open and should ideally display zero or some other default value.

Alternate, provided the input to ANxx2 pin that time ANxx0 and AN001 show the value between 0 to 30 (floating value this value is okay) but ANxx2 and ANxx3 show the near value indeed ANxx3 open.

Why this happened?

Is there any setting nonstop scan mode to set the open ANxxx port to zero?
Are there any h/ w changes need to do?

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