This has taken large number of man hours to debug and get working, it demonstrates how the M4 can be interfaced to WeMos SD card shield. The code initialises the SD card, mounts and reads the FAT32 partition. Subsequently we read bitmap files from the FAT32 partition and display the contents to the LCD display (320x240). Code is written using the FreeRTOS bsp and executes on the M4 while the A9 boots linux. Each bitmap file is 230400 bytes and when reading 720 byte blocks throughput is around 230KB/sec. As normal more info on the blog.
