CMS32L051 User Manual |Chapter 14 Serial interface IICA
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Figure 14-26 Steps to communicate an appointment
stop interrupt request
STTn=1
define communication
preservation
Wait
MSTSn=0？
release communication
preserve
IICAn=xxH
enable interrupt request
Yes
(generate start condition)
( communication
preservation )
note2
set STTn flag to '1'
(communication preserve)
define as in communication preserve state.
( to configure and set user flag of any RAM)
ensure wait time via software.
Note 1
.
confirm communication preservation
clear user flag
Write IICAn。
No
Note 1 The wait times are as follows: (config value for IICWLn + config valuefor IICWHn +4)/f
MCK
+t
F
×2
2. Write IICA shift register n (IICAn) by stopping conditional interrupt requests while the communication reservation
is running.
Note 1. STTn : Bit1 of IICA control register n0 (IICCTLn0).
MSTSn : bit7 of IICA status register n (IICSn).
IICAn : IICA shift register n
IICWLn : IICA low level 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
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