PSOC5 RTFM — Read The Fine Manual — NON Analog Pins On PSOC5!

I just got bit by Weasley wording of PSOC5LP data sheet!

PSoC® 5LP: CY8C58LP Family Datasheet Programmable System-on-Chip (PSoC®)

.

*Route any digital or analog peripheral to any GPIO

NO! You Can’t Do That (from a NON-RTFM point of view)! There is an App Note which explains this issue. Basically, the SIO port (port 12) is NOT available for ANALOG, because it is NOT a GPIO! It looks like one, acts like one, but it is not.

The reason is explained in AN58304, page 2. NONE of the P12 pins are connected to the ANALOG Bus!

Why?

Because these pins can handle 6 volts on their inputs, even with power removed. Therefore, they cannot be hooked to the analog bus because it would blow up the internals if input voltage ever exceeded the VDDA, especially with power removed

Fini

Watch Out For Marketing Claims! They are correct, but require more information before you understand them.