R1EX24002ASAS0A_15 Datasheet, PDF (13/26 Pages) Renesas Technology Corp – Two-wire serial interface 2k EEPROM (256-word × 8-bit)

R1EX24002AxxS0A
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
2k
Note:
Device address word (8-bit)
Device code (fixed)
1
0
1
0
1. R/W=“1” is read and R/W = “0” is write.
Device address code
A2
A1
A0
R/W code*¹
R/W
REJ03C0354-0101 Rev.1.01 Jan. 9, 2009
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