Readback of a protected chip?

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Hi, What would I get if I tried to read back a protected chip? I have tried to read a chip, and what I got was: the low byte of the address at each address.

I'd expected all zeros, or an error message.

In the meantime I figured out how to read back the lock bits. They read back as 0x3c. This would indeed mean that the lockdown is activated (LB1 = 0 , LB2 = 0)....

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Quote:

I'd expected all zeros, or an error message.

No what you actually get is:
Quote:

the low byte of the address at each address.

That's exactly how it protects the contents - just passes the incrementing address rather than the data. Whether it was that, all 0x00 or all 0xFF it would still be unusable and means that the authors intellectual property rights are maintained.

If you want to do this for illegal purposes it costs about $500 at some Far Eastern "labs" to get the lockbits cracked.

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Nah! I was just trying to be careful to be able to go back the way it was before flashing in the open source software... Apparently they don't want me to use their software and I'll have to use the open source one.... Thanks for confirming my observations.