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The attached project for the Embedded Artists board was created as a test of the bandwidth of SDRAM/MCI/AHB bus.
As a gimmick we made this a simple video player: Uncompressed video frames (bitmaps) and uncompressed audio are stored on an SD card. Both video and audio are continuously transferred to SDRAM via DMA. Video frames are then displayed on a TFT screen, and audio is sent via DMA to an external stereo audio DAC on I2S.
The application supports the QVGA (320x240) and WVGA (800x480) TFT boards of Embedded Artists.
With the 800x480 7" WVGA board, the TFT refresh rate is 65 Hz, and the average read speed of the SD card is 7.6 MiB/s, an impressive demonstration of the high bandwidth capabilty of the LPC1788 bus system and peripherals.