2-WIRE CMOS SERIAL E2PROM FOR DIMM SERIAL PRESENCE DETECT

S-34C02A

Seiko Instruments Inc.

11

5. Device Addressing

To start the transmission, the master device on the system generates a start condition for the slave address. After that,

the master device transmits the 7-bit device address and the 1-bit Read/Write instruction code to the SDA bus.

In the S-34C02A, the higher 4 bits of the device address are device cord, and are fixed at “1010”.

The next 3 bits of the device address are slave address. This address is used to select the devices on the system bus,

and is compared with the address value which is set beforehand by the address input pins (A0, A1, A2). If the

comparison result matches, the slave address sends an acknowledgment signal back at the 9th clock of cycle.

Slave Address

1

0

1

0

A2

A1

A0

R / W

Device Code

MSB

LSB

Figure 9 Device Address