Section 17 I2C Bus Interface 2 (IIC2)
Transmit Operation
In transmit mode, transmit data is output from SDA, in synchronization with the fall of the transfer
clock. The transfer clock is output when MST in ICCR1 is 1, and is input when MST is 0. For
transmit mode operation timing, refer to figure 17.14. The transmission procedure and operations
in transmit mode are described below.
1. Set the ICE bit in ICCR1 to 1. Set the MST and CKS3 to CKS0 bits in ICCR1 to 1. (Initial
setting)
2. Set the TRS bit in ICCR1 to select the transmit mode. Then, TDRE in ICSR is set.
3. Confirm that TDRE has been set. Then, write the transmit data to ICDRT. The data is
transferred from ICDRT to ICDRS, and TDRE is set automatically. The continuous
transmission is performed by writing data to ICDRT every time TDRE is set. When changing
from transmit mode to receive mode, clear TRS while TDRE is 1.
1
2
7
8
1
7
8
1
SCL
SDA
(Output)
Bit 6
Bit 7
Bit 0
Bit 6
Bit 7
Bit 0
Bit 0
Bit 1
TRS
TDRE
ICDRT
ICDRS
Data 1
Data 2
Data 3
Data 3
Data 1
Data 2
User
processing
[3] Write data
to ICDRT
[3] Write data
to ICDRT
[3] Write data [3] Write data
to ICDRT to ICDRT
[2] Set TRS
Figure 17.14 Transmit Mode Operation Timing
Rev. 3.00 Sep. 10, 2007 Page 355 of 528
REJ09B0216-0300
RENESAS [ RENESAS TECHNOLOGY CORP ]
