embedded - Serial protocol for sending image data -


we have custom-built microcontroller card (st32 / arm cortex m3) has camera attached. camera captures 10-bit greyscale @ 1280x1024 resolution. need send image data pc host on serial. that's quite big chunk of data; @ 115200 baud transfer 3 minutes, assuming goes fine. implement ensure robustness seem slow process down (eg split blocks, checksum blocks, ask resend if corrupt). wondering how people might make compromise between speed , integrity.

we seeing real transfer times of 6 minutes. had set uart baud rate @ weird value - 1036800 - because @ 115200 there issues (pc running @ 115200). i'm more software hardware thoughts why might happen helpful!

start doing easy compression on image.

either run-length encoding or delta encoding give less data send.

there better algorithms tiff may want trade off complexity of tiff-ing buffer easier software on embedded side.

then can afford simple xmodem compressed data.

that has useful property of being standard protocol too.

that might lead using terminal+xmodem transfer style interface host. make debugging interface pretty simple too.


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