R01UH0823EJ0100 Rev.1.00
Page 1179 of 1823
Jul 31, 2019
RX23W Group
35. I
2
C-bus Interface (RIICa)
35.10.3
Issuing a Stop Condition
The RIIC issues a stop condition when the ICCR2.SP bit is set to 1.
When the SP bit is set to 1, a stop condition issuance request is made and the RIIC issues a stop condition when the
ICCR2.BBSY flag is 1 (bus busy state) and the ICCR2.MST bit is 1 (master mode).
A stop condition is issued in the following sequence.
Stop condition issuance
(1) Drive the SDA0 line low (high level to low level).
(2) Ensure the low-level period of SCL0 line set in the ICBRL register.
(3) Release the SCL0 line (low level to high level).
(4) Detect a high level of the SCL0 line and ensure the time set in the ICBRH register and the stop condition setup time.
(5) Release the SDA0 line (low level to high level).
(6) Ensure the time set in the ICBRL register and the bus free time.
(7) Set the BBSY flag to 0 (to release the bus mastership).
Figure 35.38
Stop Condition Issue Timing (SP Bit)
TRS
STOP
MST
BBSY
IIC
Write 1 to SP bit
ICBRH
ICBRL
TDRE
ICBRL
ICBRH
ACK/NACK
ICBRL
ICBRH
8
9
P
Bus free time
Setup time
SP
Set STOP flag to 0
Accept stop condition issuance
Issue stop
condition
ICBRL
b0
SCL0
SDA0