The spec usually quotes 12V, but for reliability I would advise using 13V, often 12V isn't quite enough - if it works fine with your 12V and the PIC you are using, fair enough. But it may not work with all PIC's.
It just my hobby, just to gain my knowledge... after this I try to make LED flasher... anyway i don't has any idea yet... you has a good website to make my hobby more interesting?
The differences are very slight, there's a couple of lines included to make the 16F628 more like an 84 - these are commented and should be removed for an 84, you should also alter the header and config settings.
But the main problem is the lack of I/O pins on an 84, far better to use it's modern replacement (the 628) rather than the obselete 84 - particularly as the 628 is considerably cheaper.
The differences are very slight, there's a couple of lines included to make the 16F628 more like an 84 - these are commented and should be removed for an 84, you should also alter the header and config settings.
But the main problem is the lack of I/O pins on an 84, far better to use it's modern replacement (the 628) rather than the obselete 84 - particularly as the 628 is considerably cheaper.
The differences are very slight, there's a couple of lines included to make the 16F628 more like an 84 - these are commented and should be removed for an 84, you should also alter the header and config settings.
But the main problem is the lack of I/O pins on an 84, far better to use it's modern replacement (the 628) rather than the obselete 84 - particularly as the 628 is considerably cheaper.