Renesas H8S Series Hardware Manual page 567

Bit Bit Name Initial Value R/W
2 BBSY 0
0 SCP 1
Description
1
R/W* Bus Busy
W Start Condition/Stop Condition Prohibit
In master mode:
•
Writing 0 in BBSY and 0 in SCP: A stop condition is
issued
•
Writing 1 in BBSY and 0 in SCP: A start condition and
a restart condition are issued
In slave mode:
•
Writing to the BBSY flag is disabled.
[BBSY setting condition]
When the SDA level changes from high to low under the
condition of SCL = high, assuming that the start condition
has been issued.
[BBSY clearing condition]
When the SDA level changes from low to high under the
condition of SCL = high, assuming that the stop condition
has been issued.
To issue a start/stop condition, use the MOV instruction.
2
The I C bus interface must be set in master transmit mode
before the issue of a start condition. Set MST to 1 and
TRS to 1 before writing 1 in BBSY and 0 in SCP.
The BBSY flag can be read to check whether the I
(SCL, SDA) is busy or free.
The SCP bit is always read as 1. If 0 is written, the data is
not stored.
2
Section 16 I C Bus Interface (IIC)
Rev. 3.00 Jul. 14, 2005 Page 519 of 986
REJ09B0098-0300
2
C bus