Plug-and-play Physical Computing with Jacdac

Physical computing is becoming mainstream. More people than ever-from artists, makers and entrepreneurs to educators and students-are connecting microcontrollers with sensors and actuators to create new interactive devices. However, physical computing still presents many challenges and demands many skills, spanning electronics, low-level protocols, and software-road blocks that reduce participation. While USB has made connecting peripherals to a personal computing device (PC) trivial, USB components are expensive and require a PC to operate. This makes USB impractical for many physical computing scenarios where cost, size and low power operation are often important. We introduce Jacdac, an open-source hardware and software platform that brings the user experience of USB to physical computing at a fraction of the cost and resource requirements. It combines an intuitive connector, standardized hardware and software interfaces, a simple bus-based protocol that runs on virtually any microcontroller, and integration with Microsoft MakeCode for the micro:bit. In this way, Jacdac provides a low-cost, extensible web-based plug-and-play experience for physical computing. We evaluated Jacdac in an international hackathon involving over 80 participants who built functional artifacts with Jacdac. Interviews reveal that users find Jacdac intuitive and appreciate the plug-and-play experience where sensors and actuators are automatically discovered by the web browser in real-time.