I 2 C-Bus Transmit Data Register (Icdrt); I 2 C-Bus Receive Data Register (Icdrr); I 2 C-Bus Shift Register (Icdrs) - Renesas RX100 Series User Manual

RX13T Group
2
24.2.15 I C-bus Transmit Data Register (ICDRT)
Address(es): RIIC0.ICDRT 0008 8312h
b7 b6
1 1
Value after reset:
When the ICDRT register detects a space in the I
written to the ICDRT register to the ICDRS register and starts transmitting data in transmit mode.
The double-buffer structure of the ICDRT register and the ICDRS register allows continuous transmit operation if the
next transmit data has been written to the ICDRT register while the ICDRS register data is being transmitted.
The ICDRT register can always be read and written. Write transmit data to the ICDRT register once when a transmit data
empty interrupt (TXI) request is generated.
2
24.2.16 I C-bus Receive Data Register (ICDRR)
Address(es): RIIC0.ICDRR 0008 8313h
b7 b6
0 0
Value after reset:
When 1 byte of data has been received, the received data is transferred from the I
ICDRR register to enable the next data to be received.
The double-buffer structure of the ICDRS register and the ICDRR register allows continuous receive operation if the
received data has been read from the ICDRR register while the ICDRS register is receiving data.
The ICDRR register cannot be written. Read data from the ICDRR register once when a receive data full interrupt (RXI)
request is generated.
If the ICDRR register receives the next receive data before the current data is read from the ICDRR register (while the
ICSR2.RDRF flag is 1), the RIIC automatically holds the SCL clock low one cycle before the RDRF flag is set to 1 next.
2
24.2.17 I C-bus Shift Register (ICDRS)
b7 b6
Value after reset: — —
The ICDRS register is an 8-bit shift register to transmit and receive data.
During transmission, transmit data is transferred from the ICDRT register to the ICDRS register and is sent from the
SDA0 pin. During reception, data is transferred from the ICDRS register to the ICDRR register after 1 byte of data has
been received.
The ICDRS register cannot be accessed directly.
R01UH0822EJ0100 Rev.1.00
Jul 31, 2019
b5 b4 b3 b2
1 1 1 1
2
C-bus shift register (ICDRS), it transfers the transmit data that has been
b5 b4 b3 b2
0 0 0 0
b5 b4 b3 b2
— — — —
b1 b0
1 1
b1 b0
0 0
2
b1 b0
— —
2
24. I C-bus Interface (RIICa)
C-bus shift register (ICDRS) to the
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