Thank you for your interest in Freescale kinetis product, I would like to provide service for you.
Actually, the datasheet have the max frequent for K60 SPI operation frequency.
About the Master mode, the SPI max operation frequency is 25Mhz.
About the Slave mode, the SPI max operation frequency is 12.5Mhz.
For details, please refer to document K60P144M100SF2V2.pdf, the document link is: http://cache.freescale.com/files ... on&fileExt=.pdf
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