Renesas RL78/G1H User Manual

RL78/G1H CHAPTER 15 SERIAL INTERFACE IICA
R01UH0575EJ0120 Rev. 1.20 Page 474 of 920
Dec 22, 2016
Figure 15 - 37 Master Operation in Multi-Master System (3/3)
Remark 1. Conform to the specifications of the product that is communicating, with respect to the transmission and reception
formats.
Remark 2. To use the device as a master in a multi-master system, read the MSTSn bit each time interrupt INTIICAn has occurred to
check the arbitration result.
Remark 3. To use the device as a slave in a multi-master system, check the status by using the IICA status register n (IICSn) and
IICA flag register n (IICFn) each time interrupt INTIICAn has occurred, and determine the processing to be performed
next.
Remark 4. n = 0, 1
Communication processing
C
Writing IICAn
WTIMn = 1
WRELn = 1
Reading IICAn
ACKEn = 1
WTIMn = 0
Writing IICAn
Yes
TRCn = 1?
Restart?
MSTSn = 1?
Starts communication
(specifies an address and transfer direction).
Starts transmission.
No
Yes
Waits for data reception.
Starts reception.
Yes
No
INTIICAn
interrupt occurs?
Yes
No
Transfer end?
Waits for detection of ACK.
Yes
No
INTIICAn
interrupt occurs?
Waits for data transmission.
Does not participate
in communication.
Yes
No
INTIICAn
interrupt occurs?
No
Yes
ACKDn = 1?
No
Yes
No
2
Yes
MSTSn = 1?
No
Yes
Transfer end?
No
Yes
ACKDn = 1?
No
2
Yes
MSTSn = 1?
No
2
C
Yes
EXCn = 1 or COIn = 1?
No
1
2
SPTn = 1
STTn = 1
Slave operation
END
Communication processing
ACKEn = 0
WTIMn = 1
WRELn = 1
Waits for detection of ACK.
Yes
No
INTIICAn
interrupt occurs?
Yes
MSTSn = 1?
No
2

Renesas RL78/G1H Specifications

General

Brand	Renesas
Model	RL78/G1H
Category	Microcontrollers
Language	English