HD6433694 Datasheet, PDF (293/432 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series

17.2 Input/Output Pins
Pins used in the EEPROM are listed in table 17.1.
Table 17.1 Pin Configuration
Pin name
Symbol
Serial clock pin SCL
Serial data pin SDA
Input/Output
Input
Input/Output
Function
The SCL pin is used to control serial input/output data
timing. The data is input at the rising edge of the
clock and output at the falling edge of the clock. The
SCL pin needs to be pulled up by resistor as that pin
is open-drain driven structure of the I²C pin. Use
proper resistor value for your system by considering
V_OL, I_OL, and the C_IN pin capacitance in section 21.2.2,
DC Characteristics and in section 21.2.3, AC
Characteristics. Maximum clock frequency is 400
kHz.
The SDA pin is bidirectional for serial data transfer.
The SDA pin needs to be pulled up by resistor as that
pin is open-drain driven structure. Use proper resistor
value for your system by considering V_OL, I_OL, and the
C_IN pin capacitance in section 21.2.2, DC
Characteristics and in section 21.2.3, AC
Characteristics. Except for a start condition and a
stop condition which will be discussed later, the high-
to-low and low-to-high change of SDA input should be
done during SCL low periods.
17.3 Register Description
The EEPROM has a following register.
• EEPROM key register (EKR)
17.3.1 EEPROM Key Register (EKR)
EKR is an 8-bit readable/writable register, which changes the slave address code written in the
EEPROM. The slave address code is changed by writing H'5F in EKR and then writing either of
H'00 to H'07 as an address code to the H'FF09 address in the EEPROM by the byte write method.
EKR is initialized to H'FF.
Rev. 4.00, 03/04, page 265 of 400