LE24CB1283 Datasheet, PDF (7/12 Pages) Sanyo Semicon Device – Two Wire Serial Interface EEPROM (128K EEPROM)

LE24CB1283
5. Device addressing
To transmit between the bus master and slave device (EEPROM), the master must send a Start condition to the
EEPROM. The device address word of the EEPROM consists of 4-bit Device Code, 3-bit Slave Device address code
and 1-bit read/write code. By sending these, it becomes possible to communicate between the bus master and the
EEPROM.
The upper 4-bit of the device address word are called the Device Code, the Device Code of the EEPROM uses 1010b
fixed code. This device has the 3-bit of the Slave Device address as the Slave address (S0, S1, S2), so it can connect
up to eight device on the bus.
When the Device Code is received on the SDA, the device only responds if Slave address pin tied to VDD or GND is
the same as the Slave address signal input. The 8^th bit is the read/write bit. The bit is set to 1 for Read operation and 0
for Write operation. If a match occurs on the Device Code, the corresponding device gives an acknowledgement on
SDA during the 9^th bit time. If device does not match the Device Code, it deselects itself from the bus, and goes into
the Standby mode. Use the Random Read command when you execute reading after the slave device was switched.
Device code
Slave
Address
1
0
1
0
S2
S1
S0 R/W
MSB
LSB
Device Address word
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