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Can I erase PIC12c508a using UV eraser?

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Junior Member level 1
Apr 30, 2006
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erasing OTP 12c508a and 509 using UV eraser, is it possible,

any help is needed here, for i am trying to build a halogen 50w controller for my bike,


Re: ERASING PIC12c508a

Not unless they are the 12c508ajw "windowed" type specifically made for prototyping. They do now make 12f508a chips that are flash based and are re-programmable.

Re: ERASING PIC12c508a

As stated above only the windowed version is re-programmable.

OTP means "One Time Programmable"
After programming the PIC cannot be erase.

For prototyping use a simulator for testing the code, a flash version like 12F5xx then export the code for 12C508 or use a windowed version of the 12C508. You have several choices.

Re: ERASING PIC12c508a

thanks a lot GUYS, now i know why?

hopefully that re programmable version of the said PIC shall and will be available soon here in my country..PHILIPPINES for even the 508a verse are hard to find

Re: ERASING PIC12c508a

For the future, when you are developping your code, do not fill the first few locations. Use a goto instruction in the first locations instead. Do not set the code protection bit.
If later it becomes necessary to change the code, then comment out the first goto, replace it with a nop and then add a goto that points to the new code. Leave the old code alone.
This way you can re-program the part, since th nop will overwrite the goto (nop code is all zeroes, which overrides any ones another instruction code may have).

Once you are done developping the code, either protect the part or program a new one with just the correct code and protect it.

I have used this approach and re-used a parts about 10 times. Of course, all the versions of the code must fit in the program memory space and you need to leave enough empty locations at the beginning to add goto instructions.

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