Users Manual

Table Of Contents
R01UH0823EJ0110 Rev.1.10 Page 1082 of 1852
Nov 30, 2020
RX23W Group 33. Serial Communications Interface (SCIg, SCIh)
33.8.4 Relationship between Clock and Transmit/Receive Data
The CKPOL and CKPH bits in the SPMR register can be used to set up the clock for use in transmission and reception in
four different ways. The relation between the clock signal and the transmission and reception of data is shown in
Figure
33.58
. The relation is the same for both master and slave operation.
Figure 33.58 Relation between Clock Signal and Transmit/Receive Data in Simple SPI Mode
SMISOn pin
SCKn pin
(CKPOL = 1)
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6
Bit 7
SSn# pin
(slave)
SCKn pin
(CKPOL = 0)
(1) When CKPH = 0
SMOSIn pin
SCKn pin
(CKPOL = 1)
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6
Bit 7
SSn# pin
(slave)
SCKn pin
(CKPOL = 0)
(2) When CKPH = 1
SMOSIn pin
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6
Bit 7
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6
Bit 7
SMISOn pin
One unit of transfer data (character or frame)