BAT32G1x9 user manual | Chapter 20 Serial interface IICA
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Rev.1.02
Figure 20-28: Master operation of a multi-master system (3/3).
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C
Write IICAn
Start communication.
(Specify address and transfer
direction)
does INTIICAn interrupt
occur?
wait for detecing
acknowledgement
No
Yes
MSTSn=1
?
Yes
ACKDn=1
?
TRCn=1
?
WTIMn=1
Write IICAn
does INTIICAn interrupt
occur?
wait for transmitting
data
No
Yes
MSTSn=1
?
Yes
ACKDn=1
?
start transmission
Yes
2
No
Yes
Yes
transmission completes?
restart?
Yes
Yes
STTn=1
C
SPTn=1
END
No
No
2
No
ACKEn=1
WTIMn=0
WRELn=1
does INTIICAn interrupt
occur?
wait for receiving
data
No
MSTSn=1
?
2
No
Yes
Read IICAn
transmission completes?
start
receiving
Yes
Yes
ACKEn=0
WTIMn=1
WRELn=1
does INTIICAn interrupt
occur?
No
MSTSn=1
?
2
No
Yes
Yes
wait for detecing
acknowledgement
No
2
EXCn=1 or COIn=1?
slave operation
Yes
1
No
does not participant
communication
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No
Remarks: 1
The format of transmission and reception must conform to the specifications of the product in the
communication.
2. In the case of being used as a master device in a multi-master system,
the
MSTSn
bit must be read at each
time an
INTIICAn
interrupt
occurs to confirm the arbitration result.
3. In the case of being used as a slave in a multi-master system, the
IICA
status register
n
(IICSn) and
the IICA
flag register must be
passed at
each
INTIICAn
interrupt
n
(IICFn) confirms the status and decides on future
processing.
4. n=0.1