Tessel has four module ports, labeled A, B, C, and D.
In the examples below, port "A" is always specified. But as long as you change the port in the code, you can plug your module into any of the ports.
It's best to unplug Tessel from power while plugging in modules.
At the bottom of this page are walkthroughs for the connection and installation of each module.
Modules should be plugged in so that all of the electrical components are face up and all the hexagons are face down:
If you've already tried out your modules, move on to Wifi.