RL78/G1P
CHAPTER 12 SERIAL INTERFACE IICA
R01UH0895EJ0100 Rev.1.00
545
Nov 29, 2019
Figure 12-33. Example of Slave to Master Communication
(8-Clock Wait Is Selected for Master, 9-Clock Wait Is Selected for Slave) (2/3)
(2) Address ~ data ~ data
IICAn
STTn
(ST trigger)
SPTn
(SP trigger)
ACKDn
(ACK detection)
WTIMn
(8 or 9 clock wait)
ACKEn
(ACK control)
MSTSn
(communication status)
TRCn
(transmit/receive)
SCLAn (bus)
(clock line)
WRELn
(wait cancellation)
INTIICAn
(interrupt)
SDAAn (bus)
(data line)
IICAn
STDn
(ST detection)
SPDn
(SP detection)
ACKDn
(ACK detection)
WTIMn
(8 or 9 clock wait)
ACKEn
(ACK control)
MSTSn
(communication status)
TRCn
(transmit/receive)
WRELn
(wait cancellation)
INTIICAn
(interrupt)
R ACK
ACK
Master side
Bus line
Slave side
H
H
L
H
L
L
H
L
H
L
L
D
1
7 D
1
6 D
1
5 D
1
4 D
1
3 D
1
2 D
1
1 D
1
0
D
2
7
Note 1
Note 1
<5>
<7> <9>
Note 2
Note 2
<4> <8>
<11>
<10>
<12>
<6>
<3>
: Wait state by master device
: Wait state by slave device
: Wait state by master and slave devices
Notes 1.
For releasing wait state during reception of a master device, write “FFH” to IICAn or set the WRELn bit.
2.
Write data to IICAn, not setting the WRELn bit, in order to cancel a wait state during transmission by a
slave device.
Remark
n = 0, 1