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Note that DMA is very sensitive to the video timing. At the moment, only 800x600 mode works without locking up the DMA controller. - ubb-vga.c (DMA, setup_noirq, cleanup_noirq, line): replaced MMC PIO with DMA - ubb-vga.c (frame): pass physical addresses to "line" - ubb-vga.c (frame): detect if the DMA controller is stuck
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.