SH7080_09 Datasheet, PDF (991/1622 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family

Section 18 I²C Bus Interface 2 (I²C2)
(2) 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 18.14. 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. (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.
SCL
SDA
(Output)
TRS
1
2
Bit 0 Bit 1
7
8
1
Bit 6 Bit 7 Bit 0
7
8
Bit 6 Bit 7
1
Bit 0
TDRE
ICDRT
Data 1
Data 2
Data 3
ICDRS
Data 1
User
processing
[3] Write data _{[3] Write data}
to ICDRT
to ICDRT
[2] Set TRS
Data 2
Data 3
[3] Write data [3] Write data
to ICDRT
to ICDRT
Figure 18.14 Transmit Mode Operation Timing
Rev. 4.00 Dec. 15, 2009 Page 931 of 1558
REJ09B0181-0400