HD6433694 Datasheet, PDF (294/432 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series

17.4 Operation
17.4.1 EEPROM Interface
The HD64N3694G has a multi-chip structure with two internal chips of the HD64F3694G (F-
ZTAT™ version) and 512-byte EEPROM. The HD6483694G has a multi-chip structure with two
internal chips of the HD6433694G (mask-ROM version) and 512-byte EEPROM.
The EEPROM interface is the I²C bus interface. This I²C bus is open to the outside, so the
communication with the external devices connected to the I²C bus can be made.
17.4.2 Bus Format and Timing
The I²C bus format and the I²C bus timing follow section 15.4.1, I²C Bus Format. The bus formats
specific for the EEPROM are the following two.
1. The EEPROM address is configured of two bytes, the write data is transferred in the order of
upper address and lower address from each MSB side.
2. The write data is transmitted from the MSB side.
The bus format and bus timing of the EEPROM are shown in figure 17.2.
Start
condition
Slave address
R/W ACK
Upper memory
address
ACK
lower memory
address
ACK
Data
ACK
Data
Stop
conditon
ACK
SCL
1 2 34 5 6 7891
8 91
891
891
89
SDA
A15
A8
A7
A0
D7
D0
D7
D0
Legend: R/W: R/W code (0 is for a write and 1 is for a read),
ACK: acknowledge
Figure 17.2 EEPROM Bus Format and Bus Timing
17.4.3 Start Condition
A high-to-low transition of the SDA input with the SCL input high is needed to generate the start
condition for starting read, write operation.
Rev. 4.00, 03/04, page 266 of 400