HN58X24128I/HN58X24256I

Rev.4.00, Dec.14.2004, page 10 of 20

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.

Acknowledge Timing Waveform

SCL

SDA IN

SDA OUT

12

8

9

Acknowledge

out