I am new to PIC chips, have done a little research on the net & that's about it.
I want to build a couple of simple PIC projects from the net
(adaptors for using PC KB/mice on Amiga)
My question:
Can a PIC16F84 with external RC oscillator circuit, be replaced with a PIC16F628 (with internal oscillator)?
Yes, but bear in mind that it will probably run faster, the 628 internal oscillator is 4MHz - usually RC oscillators run slower than that. The 628 will work with an external RC oscillator as well, it's pretty well a 'drop in' replacement for the 16F84.