Vdc on serial1 of mega 2560

hi, im wondering if i should be seeing 1.85 vdc on my serial1 port of my mega 2560?
i only see less than a volt on serial2 and 3. theres no program in mega

If there is no program running on the Mega (blank or bare minimum sketch loaded) the pins will be in their default state of INPUT. They are high impedance inputs and the meter will show whatever noise that the meter leads are picking up from the environment. There is no power from the chip on those pins. They are floating.

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thank you very much for your time and energy!!

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