R1EX24032ASAS0G_15 Datasheet, PDF (8/18 Pages) Renesas Technology Corp – Two-wire serial interface 32k EEPROM (4-kword × 8-bit)

R1EX24032ASAS0G/R1EX24032ATAS0G
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 in the order of
A2, A1, A0. The device address code selects one device out of all 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-A0 pin
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
low and a read operation is initiated if this bit is high. Upon a compare of the device address word, the EEPROM enters
the read or write operation after outputting the zero as an acknowledge. 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 A0 to A2.
Device Address Word
Device address word (8-bit)
Device code (fixed)
Device address code
32k
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
R10DS0081EJ0300 Rev.3.00
Jan 30, 2014
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