Fast Question (regarding code protection and pic16f628a)

[mabauti]

The pic16f628 will be totally unusable if I activated the code protection bit?

I won't be able to program it anymore?

 

[Nigel Goodwin]

No, you just erase it and use it again - however, there seems no reason to set the protection bits, so why bother?.

But what you must NEVER, EVER do is set code protection bits on expensive UV eraseable PIC's, it does render those unuseable.

 

[wmmullaney]

The pic16f628 will be totally unusable if I activated the code protection bit?

I won't be able to program it anymore?

The pic16f628 is flash, so just reblow the fuses.

 

[Diver300]

No, you just erase it and use it again - however, there seems no reason to set the protection bits, so why bother?.

I'm probably being naive here, but I thought that the code protection bits stopped the code being read by a programmer? Doesn't that make it more difficult for someone to read and steal the code on the PIC?

Whenever I have set the protection bits, the programmer shows all the code as zeros, even when the code can still run.

 

[BeeBop]

I'm probably being naive here, but I thought that the code protection bits stopped the code being read by a programmer? Doesn't that make it more difficult for someone to read and steal the code on the PIC?

Whenever I have set the protection bits, the programmer shows all the code as zeros, even when the code can still run.

Yes, that is the whole idea behind code protection, so I don't think you are naive at all.

There have been people who claim to have foiled this, but I think it is very difficult to do, even when using destructive methods. I read, just yesterday, on a Microchip app note, their disclaimer concerning this. I wish I could find that app note, I'd take a quote from it.

 

[mvs sarma]

Yes, that is the whole idea behind code protection, so I don't think you are naive at all.

There have been people who claim to have foiled this, but I think it is very difficult to do, even when using destructive methods. I read, just yesterday, on a Microchip app note, their disclaimer concerning this. I wish I could find that app note, I'd take a quote from it.

There are agencies elsewhere, who are able to reverse engineer and retrieve the code, even if locked. Perhaps they charge for their service (may be more than the cost of new program). But in general, code protection is useful to some extent to hold piracy of the resident software.

 

[Nigel Goodwin]

I'm probably being naive here, but I thought that the code protection bits stopped the code being read by a programmer? Doesn't that make it more difficult for someone to read and steal the code on the PIC?

If you're sellling pre-programmed chips it obviously makes sense to code protect them, to help reduce piracy. However, if you're NOT selling them, then why code protect for no reason?.

In that case it's unlikely you would want to erase the chip and use it again anyway, you'd just sell the customer a new chip

 

[Diver300]

If you're sellling pre-programmed chips it obviously makes sense to code protect them, to help reduce piracy. However, if you're NOT selling them, then why code protect for no reason?.

In that case it's unlikely you would want to erase the chip and use it again anyway, you'd just sell the customer a new chip

I'm selling devices that contain PICs. They are surface mounted. It is far easier to reprogram in situ than to change the chip. I can still sell my new program.

I never code protect stuff that isn't being sold.