27SF512 chips how to code them so no one can read or copy of mapping?

[racingjoe66]

Hello guys, I am wanting to protect my mapping on my chips so only I can read them and no one else can and or copy my chips. What do I need to do? I am useing the Moates Burn 2 programmer and 27SF512 chips.Thanks,Joe

[1320_john]

If the ECM can read the chip, so can anyone else. Microcontrollers typically allow you to protect the code within them, but in that instance, the code is on the same chip as the microprocessor. Within most ECMs, the PROM and microprocessor are on the PCB. Pop the PROM, then read the contents!

[racingjoe66]

I am working on a Snowmobile ECU. I have some aftermarket chips that are protected and which you can't read them. When you do all the values are the same #. I have a ton of chips for my snowmobile and just want to protect some that I have made.

[1320_john]

Are you sure they aren't protected against writing? The Atmel EEPROMs that I use have that capability. You can send some commands to them and they are locked against writing. The microprocessor in your ECU reads the PROM to get the data. If the chip was protected against reading, the microprocessor can't see the data either. [what follows is from my recollection] Old Arcade cabinet video games used to scramble the data on the EPROM. They would use special microprocessors that would descramble the data on the fly. The EPROM would still output data and wasn't special in any way, but you needed a key to descramble the data. You also needed the key to encrypt the data on the EPROM. I think each uP had a unique key. This has slowed some of the video game historians from preserving a few of the video games.

[racingjoe66]

I know they used to say you needed to buy there decoder box as they would call it to go along with there chip and plug it into the port where you would plug in a computer to monitor the system or there chip wouldn't work. I will have to try this out as I do have there decoder box and chip. But I have people that say they have there chip and run it without the decoder box with no issues. So basically in a nut shell is there anyway I can protect my data on the chip? Sorry I am not a whiz on this stuff, I can just do the basic stuff.

[1320_john]

Let us know the brand ECU and stuff; folks here can take a look. Any idea what microprocessor the system is using? Anything is possible. The ECU manufacturer could store a key on the EPROM in a location only known to them. Maybe they are using a microcontroller with protected code to access an EPROM that is encrypted?