Regarding the frame rate, I want to clarify that I am pulling the bitmap data from an SD card via SPI given the size of the bitmap file, thus, we must not expect high-speed data transfer rates with 16-bit pictures even using the SAM3X8E HSMCI interface via PMC that operates at the masterclock/2 = 42MHz. So far, I haven't focused on the optimization of the bitmap refreshing time but functionality (Indeed, I have added few brief delays and fill functions in the code). I believe, the speed could be reduced a little bit. Of course, if the interest involves the use of shapes and text (static or dynamic), the speed data transfer will be very high (pure RAM).
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