R1EX24002ASAS0G_15 Datasheet, PDF (8/18 Pages) Renesas Technology Corp – Two-wire serial interface Two-wire serial interface

R1EX24002ASAS0G/R1EX24002ATAS0G
Preliminary
Device Addressing
The EEPROM device requires an 8-bit device address word following a start condition to enable the chip for a read or a
write operation. The device address word consists of 4-bit device code, 3-bit device address code and 1-bit
read/write(R/W) code. The most significant 4-bit of the device address word are used to distinguish device type and this
EEPROM uses “1010” fixed code. The device address word is followed by the 3-bit device address code A2, A1,A0 .
The device address code selects one device out of eight devices which are connected to the bus. This means that the
device is selected if the inputted 3-bit device address code is equal to the corresponding hard-wired A2 to A0 pins status.
The eighth bit of the device address word is the read/write(R/W) bit. A write operation is initiated if this bit is “0” and a
read operation is initiated if this bit is “1” . The EEPROM turns to a stand-by state if the device code is not “1010” or
device address code doesn’t coincide with status of the correspond hard-wired device address pins.
Device Address Word
Device address word (8-bit)
Device code (fixed)
Device address code
2k
1
0
1
0
A2
A1
A0
Note: 1. R/W=“1” is read and R/W = “0” is write.
R/W code*¹
R/W
R10DS0078EJ0100 Rev.1.00
Mar. 06, 2013
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