r5f21368sdfp Renesas Electronics Corporation., r5f21368sdfp Datasheet - Page 536

• Manufacturer Part Number: r5f21368sdfp
• Description: Renesas Mcu R8c Family / R8c/3xt-a Series
• Manufacturer: Renesas Electronics Corporation.

Under development
R8C/36T-A Group
R01UH0240EJ0001 Rev.0.01
Apr 28, 2011
Figure 21.29
21.4.3.2
In transmit mode, transmit data is output from the SDA pin in synchronization with the falling edge of the
transfer clock. The transfer clock is output when the MST bit in the SICR1 register is 1 and input when the MST
bit is 0.
Figure 21.29 shows the Operation Timing in Transmit Mode (Clock Synchronous Serial Mode).
The transmit procedure and operation in transmit mode are as follows:
(1) Set the ICE bit in the SICR1 register to 1 (transfer operation enabled). Then, set bits CKS0 to CKS3 in the
(2) Set the TRS bit in the SICR1 register to 1 to select transmit mode. This will set the TDRE bit in the SISR
(3) After confirming that the TDRE bit is 1, write transmit data to the SITDR register. Data is transferred from
SISDR register
SICR1 register
SITDR register
SICR1 register and the MST bit (initial setting).
register to 1.
registers SITDR to SISDR and the TDRE bit is automatically set to 1. Continuous transmission is enabled
by writing data to the SITDR register every time the TDRE bit is set to 1. To switch from transmit to
receive mode, set the TRS bit to 0 while the TDRE bit is 1.
SISR register
TDRE bit in
processing
TRS bit in
Program
(output)
Preliminary document
Specifications in this document are tentative and subject to change.
Transmit Operation
Operation Timing in Transmit Mode (Clock Synchronous Serial Mode)
SDA
SCL
(2) Set TRS bit to 1.
Data 1
b0
1
b1
(3) Write data to
2
SITDR register.
Data 1
b6
Data 2
7
b7
8
b0
Data 2
1
21. Clock Synchronous Serial Interface
(3) Write data to
SITDR register.
b6
7
b7
8
(3) Write data to
Data 3
Data 3
SITDR register.
b0
1
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