16x2 LCD Pi Plate -- No Display

[fidelite]

YOU ARE SUPAR GENIUS!

That did it, thank you VERY VERY much! Topside connectors FTL, I should have checked continuity between the pin I inserted in the header to the PAD of the LCD, not the pin in the hole on the LCD.

I still wish there was some kind of software method of narrowing this down, comparing the dump information from 0x20, exactly the same, still, I learned a whole lot.

[adafruit_support_bill]

I still wish there was some kind of software method of narrowing this down

Well, your read-back tests did help us narrow it down to somewhere between the port expander and the display. But since there is no read-back from the display, you need to do the last bit the old-fashioned way.