
CHAPTER 17 I
2C BUS
User’s Manual U17790EJ2V0UD
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SPTn
Stop condition trigger
0
Stop condition is not generated.
1
Stop condition is generated (termination of master device’s transfer).
After the SDA0n line goes to low level, either set the SCL0n line to high level or wait until the SCL0n
pin goes to high level. Next, after the rated amount of time has elapsed, the SDA0n line is changed
from low level to high level and a stop condition is generated.
Cautions concerning set timing
For master reception:
Cannot be set to 1 during transfer.
Can be set to 1 only when the ACKEn bit has been set to 0 and during the wait period
after the slave has been notified of final reception.
For master transmission: A stop condition cannot be generated normally during the ACK reception period. Set to
1 during the wait period that follows output of the ninth clock.
Cannot be set to 1 at the same time as the STTn bit.
The SPTn bit can be set to 1 only when in master modeNote.
When the WTIMn bit has been set to 0, if the SPTn bit is set to 1 during the wait period that follows output of
eight clocks, note that a stop condition will be generated during the high-level period of the ninth clock.
The WTIMn bit should be changed from 0 to 1 during the wait period following output of eight clocks, and the
SPTn bit should be set to 1 during the wait period that follows output of the ninth clock.
When the SPTn bit is set to 1, setting the SPTn bit to 1 again is disabled until the setting is cleared to 0.
Condition for clearing (SPTn bit = 0)
Condition for setting (SPTn bit = 1)
Cleared by loss in arbitration
Automatically cleared after stop condition is detected
When the LRELn bit = 1 (communication save)
When the IICEn bit = 0 (operation stop)
After reset
Set by instruction
Note Set the SPTn bit to 1 only in master mode. However, when the IICRSVn bit is 0, the SPTn bit must be
set to 1 and a stop condition generated before the first stop condition is detected following the switch
to the operation enabled status. For details, see 17.15 Cautions.
Caution
When the TRCn bit = 1, the WRELn bit is set to 1 during the ninth clock and the wait
state is canceled, after which the TRCn bit is cleared to 0 and the SDA0n line is set to
high impedance.
Remarks 1. The SPTn bit is 0 if it is read immediately after data setting.
2. n = 0 to 2