Max SPI speed 66 MHz?

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When searching, I came across several pages on the net indicating that the AVR32 chips had a very fast SPI speed. The datasheets seem to indicate that SPI output can be up to master clock frequency, but it seems that every other Atmel MPU only works at up to [Master Clock / 2] which would be 30 or 33 MHz for the UC3A and B chips. Has anyone ever tried running the SPI on one of these chips at top speed and found out what happens? Strange how you can get 66 MHz SPI memory chips, but yet hardly any MPU seems to support that speed.

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The maximum speed for SPI is 33MHz.
The PBA max is 66MHz though, but SPI IOs are 33MHz max.

-sma

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sma wrote:
The PBA max is 66MHz, but SPI IOs are 33MHz max.

Thanks for the info. I suspected as much, but I couldn't find anywhere in the data sheet that said "SPI IOs are 33MHz max." Where did they hide that nugget of information?

Z.

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hmm i test 2 spi modes on a display. MCK at 60 Mhz.

Mode 1:
spiclock = mck/2 = 30 mhz. Works with 32-33 FPS on a full color Display.

Mode 2:
spiclock = mck/1 = 60mhz? the spi works too, but i have now 40-41 FPS. And at 66Mhz 45fps.

I think the real spi speed in Mode 2 at 66Mhz is 40-45 Mhz.