Chassis to ground or earth ?

Hello,

I have a DIGI connect ME & Wi-ME and I don’t know to do with chassis connection.

My criterion tell me that I have to connect the chassis to earth ( not ground of 3.3V), butr digi documentation not explain the same. They say that we have to connect GROUND to chassis.

The Digi Connect ME is designed to be mounted on your PCB, and its case surrounded by your own. Does that help?