EM4170

Copyright

 2002, EM Microelectronic-Marin SA

8

www.emmicroelectronic.com

D15

D11

D07

D03

PC3

D14

D10

D06

D02

PC2

D13

D09

D05

D01

PC1

D12

D08

D04

D00

PC0

P3

P2

P1

P0

0

First bit input

Row Even Parity

Last bit input

logic "0"

Column Even Parity

Data

Word Organisation

Fig. 10

After reception of the write command, the address and the data, the EM4170 will check the parity and the Lock-Bits. If all

the conditions are fulfilled, an Acknowledge pattern (ACK) will be issued, and the EEPROM writing process will start. At the

end of programming the chip will send an Acknowledge pattern (ACK). If at least one of the checks fails, the chip will issue

a No Acknowledge pattern (NAK) instead of ACK and return to the Standby Mode.

The EM4170 might also return to the Standby Mode without sending back a NAK if the incoming data is corrupted and/or

inconsistent.

As there is no check of the power supply before writing, the system has to assure that there is enough power received by

OUTPUT

INPUT

ACK

RM

WRITE WORD ADDRESS

DATA

ACK

LIW

Write word

LIW

Fig. 11

Write Word

Begin

Receive

Address

Send

ACK

End

valid ?

Y

N

Receive

Data

Write

Data

Send

ACK

Receive

Command

Send

NAK

Fig. 12