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SSP / SSP1 questions: NSS (SSP1_NSS) and TFE (Transmit FIFO Empty)

Question asked by koenigsberg.larry on May 7, 2014
I have two questions about SSP1.  I am using it to talk as a Master to a Slave IC that requires a falling Chip Select edge at the beginning of each transmission.  Chip Select must then stay low for the duration of the transmission, and go high when the transmission is complete.

Here are my questions:  (1) Can I use SSP1_NSS for this Chip Select function?

(2) It seems that TFE (Transmit FIFO empty) cannot be used to determine when to set Chip Select high, because it appears (on the oscilloscope) that TFE is true before the last byte in the FIFO is completely shifted out to the slave.  How can I tell when the transmission is actually complete? 

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