The data in the in-memory buffer I normally send sequentially via regular 8-bit SPI is with each 16-bit RGB565 pixel MSB-first (i.e. RRRRRGGGGGGBBBBB), as expected by the display, and this works fine. However, when I try to use 8-bit DMA towards SPI I need to pre-swap the MSB and LSB for each pixel (read: I'm copying them swapped to a secondary buffer as I need the primary buffer as is) in order for the image to appear correctly on the display. What I don't understand is why this byte swapping happens for an 8-bit-to-8-bit transfer, and so far I've found no answer in the documentation.I am talking about hardware.
SPI is sending in order how it receives from DMA.
DMA takes the bytes how they are in RAM.
What is the first byte DMA sends to SPI ?
Statistics: Posted by xoblite — Sun Nov 17, 2024 1:04 am