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Hello everyone,
My trusty JDM clone has apparently reached it's limitations as it refuses to program an 18F4550, so I will defer to your expertise and opinions for advise as to which to purchase. It only has to program, and would prefer not to have a lot of off board cables and adapters.
Thank you in advance,
JS
Hi Joe,
As always, the PICKIT2. Getting to be all I use anymore.
Yep, PICKIT2. That little built in analyzer has saved my butt a few times since they came out with that firmware. And the price is right too...Quote:
Originally Posted by mackrackit
ICSP - That's using a bootloader, yes? Will the PICKIT2 work as a straight programmer like the JDM? How do I load the bootloader, and what about chips that do not support bootloader?
ICSP - not completely. ICSP - In-Circuit Serial Programming. All it means is that you don't have to keep connecting/disconnecting the programmer between code rewrites/fixes, etc. The instructions for modifying an existing circuit (or creating one for that matter are in the PICKIT2 'manual').Quote:
Originally Posted by Joe S.
Yep, like the next post says, better to say that you don't have to plug and unplug the PIC that you're programming.
Basically, you either isolate (or don't use) PGC/PGD or set it up so that the programmer doesn't try to drive anything important on PGC/PGD, MCLR gets isolated with a diode and a small resistor, Vdd can be left connected as normal as long as your circuit doesn't draw too much current.
The way I do mine is as follows:
PGC/PGD get 100 ohm resistor out to the circuit and they're connected directly to the programmer socket. That way I don't try to drive anything on PGC/PGD (RB6/RB7) with the programmer.
MCLR has a diode and 100 ohms from +5v to the MCLR pin, with MCLR connected directly to the socket. The programmer can't try to backfeed the +5v rail with Vpp from the programmer.
PIC Vdd has a diode from +5v to the Vdd pins and the Vdd pins are directly connected to the programmer socket. Lets the programmer power the PIC during programmer but keeps it from trying to power the entire circuit. If the circuit is small enough, I omit the diode on Vdd and let it power it anyways. I've been powering my circuit with the PICKIT2, drawing a bit over 100mA from it on the +5v rail for awhile now and it's still working without any problems.
This is a bit optimistic, I believe. ICSP means you don't have to remove the PIC from the circuit to reprogram it. It does not necessarily mean the circuit will run with the programmer plugged in, though. A lot of that depends on the connections and the CONFIG settings, and the circuit voltage. (Not all PIC circuits run at 5v...)Quote:
Originally Posted by skimask
Another vote for the PicKit 2. It can run and program at voltages down to 2.5v. Very handy for the new 18F J series pics.
I now only have ICSP connection on projects and have made up a couple of header to IC sockets for when I need to program a PIC out of circuit.
Also the built in Logic Tool is worth the asking price alone.
bill.
Well Gentlemen, and Ladies,
It seems the consences is PICKIT2
I guess that's in my near future.
Thank You to All who responded.
JS