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CMS32L051 User Manual |Chapter 14 Serial interface IICA
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Figure 14-28 Master operation of multi-master systems (2/3)
communication process
A
STTn=1
allow communication
preservation
prepare starting
communication. (generate
stop condition)
Wait
MSTSn=0？
C
Yes
No
does INTIICAn interrupt
occur?
Yes
EXCn=1 or COIn=1？
Yes
slave operation
No
wait to release
bus. (in
communcation
preservation)
when detecting stop condition, generate
start condition via communication
preservation function, then enter into wait
state.
wait time as following:
(IICWLn configured value+IICWHn configured value+4)/fMCK+tF 2
Note
communication process
B
IICBSYn=0？
Yes
STTn=1
Wait
D
STCFn=0？
Yes
ensure wait time via
software.
Note.
prepare starting communication.
(generate stop condition)
wait for 5 fMCK clocks
No
No
does INTIICAn interrupt
occur?
EXCn=1 or COIn=1？
Yes
slave operation
No
wait to release bus.
D
detection of stop
condition
No
C
disable communication
preservation
Note 1. IICWL: IICA low width setting register n
IICWHn: IICA high level width setting register n
t
F
: Drop time for SDAAn signal and SCLAn signal
f
MCK
: IICA operates at the clock frequency
2. n=0