sys clk
PCS
SIN
SCK
SOUT
D0
Dn
D0 D1
D2 Dn
Tcsc
Tvd_sl
Tsu_ms
Thd_ms
Tasc
Slave samples SOUT
Thd_sl
Tsu_sl
DSPI samples SIN
D1
D2
Figure 45-12. DSPI Modified Transfer Format (MTFE=1, CPHA=1, f
sck
= f
sys
/3)
DSPI samples SIN
sys clk
PCS
SIN
SCK
SOUT
Tvd_sl
D0 D1 D2 Dn
Tsu_ms
Thd_ms
Tasc
Tcsc
Slave samoles SOUD
D2D1D0 Dn
Tsu_sl
Thd_sl
Figure 45-13. DSPI Modified Transfer Format (MTFE=1, CPHA=1, f
sck
= f
sys
/4)
45.4.4.5
Continuous Selection Format
Some peripherals must be deselected between every transfer. Other peripherals must
remain selected between several sequential serial transfers. The Continuous Selection
Format provides the flexibility to handle the following case. The Continuous Selection
Format is enabled for the SPI configuration by setting the CONT bit in the SPI command.
When the CONT bit = 0, the module drives the asserted Chip Select signals to their idle
states in between frames. The idle states of the Chip Select signals are selected by the
PCSISn bits in the MCR. The following timing diagram is for two four-bit transfers with
CPHA = 1 and CONT = 0.
Chapter 45 Serial Peripheral Interface (SPI)
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
NXP Semiconductors 1167