How to program A29040B EEPROM?

Hello,

I'm trying to use Arduino to program some data into A29040B EEPROM, according to its datasheet: http://www.farnell.com/datasheets/34117.pdf.

I'm addressing EEPROM through shift register. I/O and CE, OE, WE pins are connected directly to Arduino. I think wiring and basic code functions are OK - I guess reading from EEPROM works fine. The problem is I cannot find proper sequence of CE, OE, WE and commands for programming data.
As I understand this datasheet properly, sending data is done by setting CE=0, WE=0, OE=1, then setting address and data pins, and then latching it by setting CE=1 and WE=1... then repeat.

To store data, first I have to set 3 commands:

  1. addr: 0x555, data: 0xAA
  2. addr: 0x2AA, data: 0x55
  3. addr: 0x555, data: 0xA0
    and then sequentially my own addresses/data. After finishing nothing have to be done(?)

Is it how it should be? I tried it in many ways (different CE, WE, OE combinations) and I even noticed one time that some data changed, but it had to be totally random and I couldn't repeat this "success" :)))

Any help would be very appreciated :slight_smile:
Thanks,
Laskipaa.