HN58X2402/58X2404/58X2408/58X2416/58X2432/58X2464-SR

10

Functional Description

Start Condition

A high-to-low transition of the SDA with the SCL high is needed in order to start read, write operation.

(See start condition and stop condition)

Stop Condition

A low-to-high transition of the SDA with the SCL high is a stop condition. The stand-by operation starts

after a read sequence by a stop condition. In the case of write operation, a stop condition terminates the

write data inputs and place the device in a internally-timed write cycle to the memories. After the

internally-timed write cycle which is specified as t

timing)

Start Condition and Stop Condition

SCL

SDA

(in)

Stop condition

Start condition

Acknowledge

All addresses and data words are serially transmitted to and from in 8-bit words. The receiver sends a zero

to acknowledge that it has received each word. This happens during ninth clock cycle. The transmitter

keeps bus open to receive acknowledgment from the receiver at the ninth clock. In the write operation,

EEPROM sends a zero to acknowledge after receiving every 8-bit words. In the read operation, EEPROM

sends a zero to acknowledge after receiving the device address word. After sending read data, the

EEPROM waits acknowledgment by keeping bus open. If the EEPROM receives zero as an acknowledge,

it sends read data of next address. If the EEPROM receives acknowledgment "1" (no acknowledgment) and

a following stop condition, it stops the read operation and enters a stand-by mode. If the EEPROM

receives neither acknowledgment "0" nor a stop condition, the EEPROM keeps bus open without sending

read data.