R01UH0823EJ0100 Rev.1.00
Page 1360 of 1823
Jul 31, 2019
RX23W Group
38. Serial Peripheral Interface (RSPIa)
38.3.3
RSPI System Configuration Examples
38.3.3.1
Single Master/Single Slave (with This MCU Acting as Master)
shows a single-master/single-slave RSPI system configuration example when this MCU is used as a master.
In the single-master/single-slave configuration, the SSLA0, SSLA1, and SSLA3 output of this MCU (master) are not
used. The SSL input of the SPI slave is fixed to the low level, and the SPI slave is maintained in a select state.
This MCU (master) drives the RSPCKA and MOSIA. The SPI slave drives the MISO.
Note 1. In the transfer format corresponding to the case where the SPCMDm.CPHA bit is 0, there are slave devices for
which the SSL signal cannot be fixed to the active level. In situations where the SSL signal cannot be fixed, the
SSLAi output of this MCU should be connected to the SSL input of the slave device.
Figure 38.5
Single-Master/Single-Slave Configuration Example (This MCU = Master)
This MCU (master)
SPI slave
RSPCK
MOSI
MISO
SSL0
SSL1
SSL2
SPCK
MOSI
MISO
SSL
RSPCKA
MOSIA
MISOA
SSLA0
SSLA1
SSLA3