"Honey, my PIC ADC pin sagged my peak detector voltage!"

[HankMcSpank]

Anyone know what to expect (voltage wise) on an analogue input pin configured for ADC with nothing connected? - I'm seeing 5V on mine (as seen on a DVM - but also I'm getting an ADC value of 255 with nothing connected to the pin - I was expecting 0?)

When I connect up say a pot wiper - it reads the incoming coltage properly....I'I'm curious to know what's going on internally at a low level electronics inside?

Edit: It seems this PIC (16f1828), doesn't disable PORTC weak pullups at initialisation, it should, this from the datasheet...

"All pull-ups are disabled on a Power-on Reset"

however I've just added the explicit line WPUC = 0 & now everything is reading 0 as expected on my Analogue/ ADC pins