Ben Blinkenlights ================= This project is a proof of concept implementation of Rikard Lindstrom's idea of using the Ben's 8:10 card slot as a general extension interface also for devices that don't speak MMC or SD/SDIO. The application is a simple LED circuit, as suggested by David Samblas. The 8:10 card slot gives access to six GPIOs, a 3.3 V supply that can be switched on and off by software, and ground. We use a simple form of multiplexing to drive ten LEDs with this interface. Note that one should only light one LED at a time. If multiple LEDs are lit, they will share the current though the common resistor, and will thus be less bright than a single LED.