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CHAPTER 16 I
2
C BUS
User’s Manual U16896EJ2V0UD
473
<7>
STCF0
Condition for clearing (STCF0 bit = 0)
• Clearing by setting the STT0 bit = 1
• When the IICE0 bit changes from 1 to 0
(operation stop)
• Reset
Condition for setting (STCF0 bit = 1)
• Generating start condition unsuccessful and the
STT0 bit cleared to 0 when communication
reservation is disabled (IICRSV0 bit = 1).
STCF0
0
1
Generate start condition
Start condition generation unsuccessful: clear STT0 flag
STT0 clear flag
IICF0
<6>
IICBSY0
5
0
4
0
3
0
2
0
<1>
STCEN0
<0>
IICRSV0
After reset: 00H R/W
Note
Address: IICF0 FFFFFD8AH
Condition for clearing (IICBSY0 bit = 0)
• Detection of stop condition
• When the IICE0 bit changes from 1 to 0
(operation stop)
• Reset
Condition for setting (IICBSY0 bit = 1)
• Detection of start condition
• Setting of the IICE0 bit when the STCEN0 bit = 0
IICBSY0
0
1
Bus release status (initial communication status when STCEN0 bit = 1)
Bus communication status (initial communication status when STCEN0 bit = 0)
I
2
C0 bus status flag
Condition for clearing (STCEN0 bit = 0)
• Detection of start condition
• Reset
Condition for setting (STCEN0 bit = 1)
• Setting by instruction
STCEN0
0
1
After operation is enabled (IICE0 bit = 1), enable generation of a start condition upon detection of
a stop condition.
After operation is enabled (IICE0 bit = 1), enable generation of a start condition without detecting
a stop condition.
Initial start enable trigger
Condition for clearing (IICRSV0 bit = 0)
• Clearing by instruction
• Reset
Condition for setting (IICRSV0 bit = 1)
• Setting by instruction
IICRSV0
0
1
Enable communication reservation
Disable communication reservation
Communication reservation function disable bit
Note
Bits 6 and 7 are read-only bits.
Cautions 1. Write to the STCEN0 bit only when the operation is stopped (IICE0 bit = 0).
2. As the bus release status (IICBSY0 bit = 0) is recognized regardless of the actual bus
status when the STCEN0 bit = 1, when generating the first start condition (STT0 bit = 1),
it is necessary to verify that no third party communications are in progress in order to
prevent such communications from being destroyed.
3. Write to the IICRSV0 bit only when the operation is stopped (IICE0 bit = 0).
<R>
<R>