Freescale Semiconductor MPC5553 - Page 922

MPC5553/MPC5554 Microcontroller Reference Manual, Rev. 5
Freescale Semiconductor 20-49
Figure 20-29. Example of Serial Chaining of DSPIs in the MPC5554
Figure 20-30. Example of Serial Chaining of DSPIs in the MPC5553
In the MPC5554 (master), the SOUT of DSPI_A is connected to the SIN of DSPI_B (slave), and in the
MPC5553 (master), the SOUT of DSPI_B is connected to the SIN of DSPI_C (slave). In the MPC5554,
the SOUT of the DSPI_B (slave) is connected to the SIN input of the DSPI_C and so on (slave). In the
MPC5553, the SOUT of the DSPI_C (slave) is connected to the SIN input of the DSPI_D and so on (slave).
The SOUT of the last on-chip DSPI slave is connected to the SIN of the external SPI slave. The SOUT of
the external SPI slave is connected to the SIN of DSPI_A master (MPC5554)/DSPI_B master (MPC5553).
The MPC5554 DSPI_A master and the MPC5553 DSPI_B master control and initiate all transfers, but the
slave DSPIs use the trigger output signal MTRIG
to indicate to the DSPI_A (MPC5554) or DSPI_B
SOUT
ht
SCK
SIN
MTRIG
SS
DSPI_A
SOUT
ht
SCK
SIN
PCS0
SIN_A
PCS_A0
SCK_A
(Master)
DSPI_B
(Slave)
SOUT
SCK
SIN
MTRIG
SS
DSPI_C
(Slave)
SOUT_C
SCKSS
SIN
Slave Device
SPI
SOUT
MPC5554
SOUT
HT
SCK
SIN
MTRIG
SS
MPC5553
DSPI_B
SOUT
HT
SCK
SIN
PCS0
SIN_B
PCS_B0
SCK_B
(Master)
DSPI_C
(Slave)
SOUT
SCK
SIN
MTRIG
SS
DSPI_D
(Slave)
SOUT_D
SCKSS
SIN
Slave Device
SPI
SOUT