R1EX24004ASAS0G Datasheet, PDF (8/18 Pages) Renesas Technology Corp – Two-wire serial interface 4k EEPROM Clock frequency

R1EX24004ASAS0G/R1EX24004ATAS0G
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 2-bit device address code A2, A1
memory address a8. The device address code selects one device out of four devices which are connected to the bus.
This means that the device is selected if the inputted 2-bit device address code are equal to the corresponding hard-
wired A2, A1 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 “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 A2 to A0.
Device Address Word
Device address word (8-bit)
Device code (fixed)
Device address code
4k
1
0
1
0
A2
A1
a8
Note: 1. R/W=“1” is read and R/W = “0” is write.
R/W code*¹
R/W
R10DS0079EJ0100 Rev.1.00
Mar. 06, 2013
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