ISaAC - A New Add-on Adapter for the Raspberry Pi

摘要

For quite a while now, we have sought the ultimate add-on interface board to enhance some Raspberry Pi (RasPi for short) projects we want to pursue, including a mobile webcam and a wireless sensor network. For such projects to work, it's essential that our RasPi add-on meet several particular criteria. For starters, its microcontroller must be easily programmable. This is important because we need to be able to offload the RasPi from the more mundane control/monitoring functions, leaving it free to do vision processing and/or web control. The add-on would also need a healthy mix of I/O -both digital and analog interfaces - and an expansion port capable of addressing custom electronics. The adapter shouldn't be larger than the RasPi to make packaging easy and it would also lend itself to better mechanical stability when mounted to the RasPi (to handle vibrations). Another necessary feature is easy access to the RasPi general-purpose input/output (GPIO), so as not to block onboard cable connectors (that is, the camera). Finally, in the interest of green design, the add-on should cycle and control power to the RasPi remotely using a real time clock calendar (RTCC) to facilitate shut-down and/or power-up.