Renesas RX Series - I 2 C-Bus Control Register 2 (ICCR2)

R01UH0823EJ0100 Rev.1.00 Page 1118 of 1823
Jul 31, 2019
RX23W Group 35. I
2
C-bus Interface (RIICa)
35.2.2 I
2
C-bus Control Register 2 (ICCR2)
Note 1. When the ICMR1.MTWP bit is set to 1, bits MST and TRS can be written to.
ST Bit (Start Condition Issuance Request)
This bit is used to request transition to master mode and issuance of a start condition.
When this bit is set to 1 to request to issue a start condition, a start condition is issued when the BBSY flag is set to 0 (bus
free state).
For details on the start condition issuance, refer to
section 35.10, Start Condition/Restart Condition/Stop Condition
Issuing Function
.
[Setting condition]
 When 1 is written to the ST bit
[Clearing conditions]
 When 0 is written to the ST bit
 When a start condition has been issued (a start condition is detected)
 When the ICSR2.AL (arbitration-lost) flag is set to 1
 When 1 is written to the ICCR1.IICRST bit to apply an RIIC reset or an internal reset
Note: Set the ST bit to 1 (start condition issuance request) when the BBSY flag is set to 0 (bus free state).
Note that arbitration may be lost due to a start condition issuance error if the ST bit is set to 1 (start condition
issuance request) when the BBSY flag is set to 1 (bus busy state).
Address(es): RIIC0.ICCR2 0008 8301h
b7 b6 b5 b4 b3 b2 b1 b0
BBSY MST TRS — SP RS ST —
Value after reset:
00000000
Bit Symbol Bit Name Description R/W
b0 — Reserved This bit is read as 0. The write value should be 0. R/W
b1 ST Start Condition Issuance
Request
0: Does not request to issue a start condition.
1: Requests to issue a start condition.
R/W
b2 RS Restart Condition Issuance
Request
0: Does not request to issue a restart condition.
1: Requests to issue a restart condition.
R/W
b3 SP Stop Condition Issuance
Request
0: Does not request to issue a stop condition.
1: Requests to issue a stop condition.
R/W
b4 — Reserved This bit is read as 0. The write value should be 0. R/W
b5 TRS Transmit/Receive Mode 0: Receive mode
1: Transmit mode
R/W*
1
b6 MST Master/Slave Mode 0: Slave mode
1: Master mode
R/W*
1
b7 BBSY Bus Busy Detection Flag 0: The I
2
C-bus is released (bus free state).
1: The I
2
C-bus is occupied (bus busy state).
R