Datasheet
Section 18 I
2
C Bus Interface 2 (IIC2) 
    Rev. 3.00 Mar. 15, 2006 Page 345 of 526 
   REJ09B0060-0300 
Bit Bit Name 
Initial 
Value R/W Description 
5 
4 
MST 
TRS 
0 
0 
R/W 
R/W 
Master/Slave Select 
Transmit/Receive Select 
In master mode with the I
2
C bus format, when 
arbitration is lost, MST and TRS are both reset by 
hardware, causing a transition to slave receive mode. 
Modification of the TRS bit should be made between 
transfer frames. 
After data receive has been started in slave receive 
mode, when the first seven bits of the receive data 
agree with the slave address that is set to SAR and the 
eighth bit is 1, TRS is automatically set to 1. If an 
overrun error occurs in master mode with the clock 
synchronous serial format, MST is cleared to 0 and 
slave receive mode is entered. 
Operating modes are described below according to 
MST and TRS combination. When clocked synchronous 
serial format is selected and MST is 1, clock is output. 
00: Slave receive mode 
01: Slave transmit mode 
10: Master receive mode 
11: Master transmit mode 
3 
2 
1 
0 
CKS3 
CKS2 
CKS1 
CKS0 
0 
0 
0 
0 
R/W 
R/W 
R/W 
R/W 
Transfer Clock Select 3 to 0 
These bits should be set according to the necessary 
transfer rate (see table 18.2) in master mode. In slave 
mode, these bits are used for reservation of the setup 
time in transmit mode. The time is 10 t
cyc
 when CKS3 = 
0 and 20 t
cyc
 when CKS3 = 1. 










