RL78/G1P
CHAPTER 12 SERIAL INTERFACE IICA
R01UH0895EJ0100 Rev.1.00
539
Nov 29, 2019
Figure 12-32. Example of Master to Slave Communication
(9-Clock Wait Is Selected for Master, 9-Clock Wait Is Selected for Slave) (3/4)
(3) Data ~ data ~ Stop condition
Master side
D
16
1
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)
D
16
2
D
16
3
D
16
4
D
16
5
D
16
0
D
16
6
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)
D
15
0
D
16
7
Bus line
Slave side
L
L
H
H
L
L
H
H
L
ACK
ACK
Note 1
Stop condition
<14>
<9>
Note 2
<8>
<12>
<7>
<11>
<15>
<10>
<13>
Note 3
Note 3
: Wait state by master device
: Wait state by slave device
: Wait state by master and slave devices
Notes 1.
Write data to IICAn, not setting the WRELn bit, in order to cancel a wait state during transmission by a master
device.
2.
Make sure that the time between the rise of the SCLAn pin signal and the generation of the stop
condition after a stop condition has been issued is at least 4.0
s when specifying standard mode and
at least 0.6
s when specifying fast mode.
3.
For releasing wait state during reception of a slave device, write “FFH” to IICAn or set the WRELn bit.
Remark
n = 0, 1