RasPi relay action

This shows my RasPi connect via i2c to 2 mcp23017 controllers and each 23017 connects to two 8 channel relay banks.

Notes:
Power to the Pi is normal 5v DC 1000mA micro-b USB connection. Power the the relay is an external 5v DC 1000mA with a 12v DC input. To make the relays function I needed to connect a ground output from the Pi to the 2nd power source.

Raspberry Pi

I have been "playing" with a couple of Raspberry Pi's for the last month, which I am learning some Debian interaction, ssh, Python coding, and raspi's GPIO.
Some of my projects are:
Timelapse camera w/ webserver.
External relay control for lights and music or home automation.
And some ideas on a solar tracker and robot.