HD64F3694HV Datasheet, PDF (309/452 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series

Section 17 EEPROM
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 , I ,
OL OL
and the C pin capacitance in section 21.2.2, DC
IN
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.5.00 Nov. 02, 2005 Page 279 of 418
REJ09B0028-0500