R01UH0823EJ0100 Rev.1.00
Page 1361 of 1823
Jul 31, 2019
RX23W Group
38. Serial Peripheral Interface (RSPIa)
38.3.3.2
Single Master/Single Slave (with This MCU Acting as Slave)
shows a single-master/single-slave RSPI system configuration example when this MCU is used as a slave.
When this MCU is to operate as a slave, the SSLA0 pin is used as SSL input. The SPI master drives the RSPCK and
MOSI. This MCU (slave) drives the MISOA.
In the single-slave configuration in which the SPCMDm.CPHA bit is set to 1, the SSLA0 input of this MCU (slave) is
fixed to the low level, this MCU (slave) is maintained in a select state, and in this manner it is possible to execute serial
transfer (
).
Note 1. When SSLA0 is at the non-active level, the pin state is Hi-Z.
Figure 38.6
Single-Master/Single-Slave Configuration Example (This MCU = Slave, CPHA = 0)
Figure 38.7
Single-Master/Single-Slave Configuration Example (This MCU = Slave, CPHA = 1)
RSPCK
MOSI
MISO
SSL0
SSL1
SSL2
SPCK
MOSI
MISO
SSL
SPI master
This MCU (slave)
RSPCKA
MOSIA
MISOA
SSLA0
SSLA1
SSLA3
RSPCK
MOSI
MISO
SSL0
SSL1
SSL2
SPCK
MOSI
MISO
SSL
SPI master
This MCU (slave, CPHA = 1)
RSPCKA
MOSIA
MISOA
SSLA0
SSLA1
SSLA3