18F4620 refuses to be re-programmed

[mister_e]

mmm, could be but if the PGM pin is not loaded, on many device (16Fs too), it doesn't work. The PGD,PGC,MCLR wires between your board and your programmer should be short. Here, under 6-8 inches, do the trick. I use a flat cable and i have a GND between all signals.

Make sure the LVP mode is disabled, make sure your supply line is clean, make sure you place few 0.1uF capacitor here and there and better are your chance it works. Usually i place 0.1+10uF tantalum close to the PIC on the Vdd line(s).

In theory, when you program the PIC.. the PIC itself don't need much current, but the hardware attach to could. Without the schematic it's a bit hard to guess. Bear in mind that when you program the PIC, all I/Os should become Hi-z... in this case it could do some strange behaviour.. or not.

Did you place the Diode on MCLR pin too?

Please be patient with people that has an I.C. lower than 150 or 180.

Sorry, i don't know what's happen to me these days.. kind of PMS... sort of

[skimask]

Sorry, i don't know what's happen to me these days.. kind of PMS... sort of

It's not your fault, it's the people that want everything and they want it right now and they don't want to do any of the work involved with getting whatever it is yesterday and not tomorrow (like those idiots that paid $1000+ for the Playstation 3 on eBay, if they wait for a month or so, they would've gotten it for retail price). Ya gotta love those 'I've got X, can somebody give me Y?'....
JDG

[mister_e]

Could be, but not in this specific thread

BTW, we're here to help and learn.. so why not doing it smooth?

[Archangel]

Sorry, i don't know what's happen to me these days.. kind of PMS... sort of

Hi mister_e,
I had that when my daughter was a teenager, it stands for PAPA MUST SUFFER !
JS