Ralph
Why is that "old" 16F84 still that popular?
IMO it's so popular because it's one of the first one. If you do a search on the web, you'll find more project with this PIC16F84. In the begining he made his popularity here in some *black box TV project* ;0)

AND, most free programmer (PONYPROG,ICPROG,EL CHEAPO... ) has been developed around this one. I still have those in stock. when i want to decrease my stock(about 300 remain as now), i use them in some simple tasks (still pain in the neck when you MUST use external oscillator... ) Like those 16C54 that i still have(about 200)... i must found something to use them :0)

BUT i heard that in some Country, this PIC16F84 is the less expensive one. Here in Montreal, if you want to experiment with PIC, local/public distributor (active, addisson, master-vox...) will hold only 16F84,16F877,12C508 and SOMETIMES at some place 16F628. This is why i do order from Digikey, Newark or else other.


Lilmanmgf

Seems like a bad PIC... i'm really not sure but. I still asking the same question. Do you program your PIC in-circuit or directly in the EPIC socket. CAse in-circuit, try to erase directly in the EPIC socket. Can you monitor the MCLR pin when you program it? Should be around 13Volts.