Information

The DSPI supports four different transfer formats:
• Classic SPI with CPHA=0
• Classic SPI with CPHA=1
• Modified Transfer format with CPHA = 0
• Modified Transfer format with CPHA = 1
A modified transfer format is supported to allow for high-speed communication with
peripherals that require longer setup times. The DSPI can sample the incoming data later
than halfway through the cycle to give the peripheral more setup time. The MTFE bit in
the MCR selects between Classic SPI Format and Modified Transfer Format.
In the SPI Configurations, the DSPI provides the option of keeping the PCS signals
asserted between frames. See Continuous Selection Format for details.
46.4.4.1 Classic SPI Transfer Format (CPHA = 0)
The transfer format shown in following figure is used to communicate with peripheral
SPI slave devices where the first data bit is available on the first clock edge. In this
format, the master and slave sample their SIN pins on the odd-numbered SCK edges and
change the data on their SOUT pins on the even-numbered SCK edges.
Functional Description
K20 Sub-Family Reference Manual, Rev. 6, Nov 2011
1240 Freescale Semiconductor, Inc.