Raspberry PI - FUN with leds and switches

In the spirit of learning more about circuits and electronics I made a few experiments with my PI, a breadboard and a bunch of leds. Each led is directly controlled by a single GPIO pin.

This one is quite simple, as it cycles 5 leds on/off periodically.

This one cycles 7 leds on/off at the push of a tactile switch. I actually had to learn a bit more for this one, since switches must operate on a logic principle implemented by something called pull-up resistors. These can be implemented with componentes on a physical circuit, but the PI’s GPIO has a logical implementation.

The next step would be to learn about multiplexing techniques as to lower the high requirement of GPIO pins (one per led). I’m yet to venture into that, though…