R01UH0822EJ0100 Rev.1.00
Page 621 of 1041
Jul 31, 2019
RX13T Group
23. Serial Communications Interface (SCIg, SCIh)
23.2.17
I
2
C Mode Register 3 (SIMR3)
Note 1. Generate a start condition only when the SSCLn and SSDAn pins are both high (the corresponding bits in the corresponding
PIDR registers are 1).
Note 2. Generate a restart or stop condition only when the SSCLn pin is low (the corresponding bit in the PIDR register is 0).
Note 3. Do not set more than one from among the IICSTAREQ, IICRSTAREQ, and IICSTPREQ bits to 1 at a given time.
Note 4. Execute the generation of a condition after the value of the IICSTIF flag is 0.
Note 5. Do not write 0 to this bit while it is 1. Generation of a condition is suspended by writing 0 to this bit while it is 1.
SIMR3 is used to control the simple I
2
C mode start and stop conditions, and to hold the SSDAn and SSCLn pins at fixed
levels.
IICSTAREQ Bit (Start Condition Generation)
When a start condition is to be generated, set both the IICSDAS[1:0] and IICSCLS[1:0] bits to 01b as well as setting the
IICSTAREQ bit to 1.
[Setting condition]
Writing 1 to the bit
[Clearing condition]
Completion of generation of the start condition
Address(es): SCI1.SIMR3 0008 A02Bh, SCI5.SIMR3 0008 A0ABh, SCI12.SIMR3 0008 B30Bh
b7
b6
b5
b4
b3
b2
b1
b0
IICSCLS[1:0]
IICSDAS[1:0] IICSTIF IICSTP
REQ
IICRST
AREQ
IICSTA
REQ
Value after reset:
0
0
0
0
0
0
0
0
Bit
Symbol
Bit Name
Description
R/W
b0
Start Condition Generation
0: A start condition is not generated.
1: A start condition is generated.*
R/W
b1
IICRSTAREQ Restart Condition Generation
0: A restart condition is not generated.
1: A restart condition is generated.*
R/W
b2
Stop Condition Generation
0: A stop condition is not generated.
1: A stop condition is generated.*
R/W
b3
Issuing of Start, Restart, or Stop
Condition Completed Flag
0: There are no requests for generating conditions or a
condition is being generated.
1: A start, restart, or stop condition is completely generated.
R/W
b5, b4
SSDA Output Select
b5 b4
0 0: Serial data output
0 1: Generate a start, restart, or stop condition.
1 0: Output the low level on the SSDAn pin.
1 1: Place the SSDAn pin in the high-impedance state.
R/W
b7, b6
SSCL Output Select
b7 b6
0 0: Serial clock output
0 1: Generate a start, restart, or stop condition.
1 0: Output the low level on the SSCLn pin.
1 1: Place the SSCLn pin in the high-impedance state.
R/W