Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

28C256 EEPROM Problem, Data automatically corrupt

Status
Not open for further replies.

kg300

Member level 3
Joined
Sep 21, 2007
Messages
67
Helped
62
Reputation
124
Reaction score
64
Trophy points
1,308
Location
RY Khan - PAK
Activity points
1,847
Hi friends, I have a problem using 28c256 EEPROM Chip. In a Chick Master Hatcher machine Board company use 28C256 Chip. I copy Data from original chip and program it in a new AT28C256 IC. Copied IC work well and oprate all the functions correct but after 3 or 4 hours (some time one day) IC software automatically corrupt and not operate properly. The orignal company IC work fine in the same circuit Board. I bout many new ICs but the problem is same.
Please cane anyone help me to solve the problem and is there any comparison of 28C256?

Thanks.
 

You try to compare the two manufacturers data for the two IC's. There seems to be supply voltage issue like 3 or 5 V or some thing similar.
After working for sometime it starts malfunctioning. Please check if it recovers on standing for some time or the data content is corrupt or lost.
 

Read datasheet for your EEPROM. It has additional software write protection:

The CAT28C256 features a software controlled data protection scheme which, once enabled, requires a data algorithm to be issued to the device before a write can be performed. The device is shipped from Catalyst with the software protection NOT ENABLED (the CAT28C256 is in the standard operating mode). To activate the software data protection, the device must be sent three write commands to specific addresses with specific data (Figure 9). This sequence of commands (along with subsequent writes) must adhere to the page write timing specifications (Figure 11). Once this is done, all subsequent byte or page writes to the device must be preceded by this same set of write commands. The data protection mechanism is activated until a deactivate sequence is issued regardless of power on/off transitions. This gives the user added inadvertent write protection on power-up in addition to the hardware protection provided.

I can guess that you have not enabled the software protection in new chip, but old original chip was written with software protection.
 

The original chip is X28HC256, I use AT28C256. Supply voltages is same of both chips (5 Volt) and after some time data content was corrupt, not lost. How can I do software protection.
 
Last edited:

May be suggestions of post #3 seems worth considering and trying. Please give it a thought !
The animated pic on the left of post #3 is funny !!
Raoof
 

Is it possible to add software write protection in Hex file? Because I just copy the data from original chip in hex format.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top