Datasheet
RL78/L12    CHAPTER 13 SERIAL INTERFACE IICA 
R01UH0330EJ0200 Rev.2.00      593 
Dec 13, 2013 
Figure 13-32. Example of Master to Slave Communication 
(9-Clock Wait Is Selected for Master, 9-Clock Wait Is Selected for Slave) (4/4) 
(4) Data ~ restart condition ~ address 
L 
H 
L 
H 
L 
H 
IICA0 
STT0 
(ST trigger) 
SPT0 
(SP trigger) 
ACKD0 
(ACK detection) 
WTIM0 
(8 or 9 clock wait)
ACKE0 
(ACK control) 
MSTS0 
(communication status) 
TRC0 
(transmit/receive)
SCLA0 (bus) 
(clock line) 
WREL0 
(wait cancellation) 
INTIICA0 
(interrupt) 
SDAA0 (bus) 
(data line)
AD6
IICA0 
STD0 
(ST detection) 
SPD0 
(SP detection) 
ACKD0 
(ACK detection) 
WTIM0 
(8 or 9 clock wait) 
ACKE0 
(ACK control) 
MSTS0 
(communication status) 
TRC0 
(transmit/receive) 
WREL0 
(wait cancellation) 
INTIICA0 
(interrupt) 
Master side 
Bus line 
Slave side 
Slave address 
D
1
3 
ACK
<i>
L 
H 
H 
L 
H 
Restart condition 
D
1
2 D
1
1 D
1
0 
AD5 AD4 AD3 AD2 
AD1
<ii>
<iii>
<7>
<8>
Note 2
Note 1
: Wait state by master device 
: Wait state by slave device 
: Wait state by master and slave devices 
Notes 1.  Make sure that the time between the rise of the SCLA0 pin signal and the generation of the start 
condition after a restart condition has been issued is at least 4.7 
μ
s when specifying standard mode and 
at least 0.6 
μ
s when specifying fast mode. 
 2.  For releasing wait state during reception of a slave device, write “FFH” to IICA0 or set the WREL0 bit. 










