>> I thought that MCLR is set up in config and has not any
>> influence on PICkit3 in finding the PIC16F628A

I'm not familiar with the PICkit3 but for programmers generally
that is true. When the programmer has control of the programming
lines it takes no notice of what's already in the PIC. It might as
well be factory-fresh with that 'new PIC' smell

> The simplest is that it has just power
>> Do you mean only + and - and that is ALL?

Yes. Look at things like the PICAXE, which needs no external
clock (eg crystal) or MCLR pull-up
--=20
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