From what I can see a level 2 charger is an extension cord between a 240-volt line and the car with a fancy plug on the car end and maybe a switch and current sensing display in the box on the wall. A good one may have a delayed start. What am I missing? Tesla has some other part the opens the car charging port cover. I do not know if anything else is special.
At minimum they have a residual current detector, a power contactor and a controller to generate a Control Pilot signal for handshaking with the EV. Go to OpenEVSE and you can see all the parts.
The pins are: pilot signal - uses a resistor network and diode to communicate between car and EVSE presence signal - uses a resistor to indicate it is connected This may help explain more: It has a small bluetooth transmitter that lets the car know to open the charging port cover. Bob Wilson
One minor mistake is the latch on the J1772 takes a resistor out of the "presence" line and signals the car to shut everything down. As for unlocking the connector, well my experience is that seems to be a gap in spec but likely car specific. Also, it doesn't really address adapters like the Tesla-to-J1772. But the "presence" line works quite fine. Bob Wilson