hi,
with ardunino mega, whats the max speed i can read from the microsd card if it is connected with SPI?
4MHz is the default speed for the SD library, but there is overhead. You might be able to boost that to 8MHz, but I haven't tried it. What are you planning on doing with the data once you read the SD card?
i will send them to a TFT via a FT800 chip. But i whant to know if i can read a video (480*272) and send it to display with out any problems with frame rate. i whant to find if the SPI has enough speed or i have to use the other faster protocoll
If you mean video, it isn't fast enough. What faster protocol is there?
edit: Do the math.
480 x 272 = 130,560 bytes for one frame at 8 bit resolution
4,000,000 / 8 = 500,000 bytes per second from SD
500,000 / 130,560 = 3.8 frames per second