Ben Heck shows up how he built his Pinball Portable project. The brain of the system is a Teensy microcontroller. He is using shift registers to lower the microcontroller pin count that is needed. This allows for a nice modular design. A output shift register is used to drive mosfets to drive high current devices such as solenoids, input shift registers are used to capture a bunch of inputs bu using just a few pins on the microcontroller. Ben is also using a nice max7221 chip to drive a 7 segment display, this allows for a serial interface to drive multiplexed 7 segments. In the second video Ben puts the electronics to work in a custom built pinball mini model most of which has been laser cut.