PicKit 2 WARNING
in [Design]
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From: David L. Jones on 15 Sep 2009 02:42 Robert Baer wrote: > Frank Buss wrote: >> David L. Jones wrote: >> >>> Robert Baer wrote: >>>> You can permanently destroy a PicKit 2 programming pod in an easy >>>> un-documented manner. >>>> 1) Tie one or more pins of a PIC MCU to ground; it does not help to >>>> have MCU program use the pin(s) as inputs. >>>> 2) Program then power up the MCU with the PicKit 2; you may need >>>> to do power down and power up a few times. >>>> ZZZZzzzzzaaaaaa:P:! No Poof, No Frap, No Zap; it just gets killed. >>>> As far as i can tell the USP port is not damaged; my 1Gbyte stick >>>> still reads OK. >> >> I have no such problems with this test setup: >> >> http://www.frank-buss.de/pic18f2550/index.html >> >> The PIC is always powered from external power in my test setup. But I >> noticed that the PicKit pulls VDD to low, if disabled, which was not >> much of a problem, because of my current limited power supply, but I >> think this could destroy the prorgammer. How does your schematic >> looks like? >>> Err, yes they are, at $35 it's one of the cheapest official >>> programmers on the market for any micro. >> >> There are some other programmers within the same price range: >> >> http://search.digikey.com/scripts/DkSearch/dksus.dll?keywords=428-2021-ND >> http://search.digikey.com/scripts/DkSearch/dksus.dll?keywords=336-1182-ND >> >> But you are right, there are more expensive ones, but then usually >> with in-circuit debugging support etc. >> > I use the same programming scheme; the +5V was not activated and i > tried running the MCU using the PicKit 2 as the power source. > > That Cypress programmer is only slightly less expensive and i think > i am better off using a "known" where all software and hardware are > from the same company. The Cypress programmer Frank pointed out is not for the PIC, it's for Cypress micro's, he was just using that as an example of pricing. I really fail to see how you can damage your PICkit2 based on your explanation of tying PIC I/O pins to ground. I think there has to be more to this... Dave. -- ================================================ Check out my Electronics Engineering Video Blog & Podcast: http://www.eevblog.com
From: David L. Jones on 15 Sep 2009 02:54 Robert Baer wrote: > David L. Jones wrote: >> Robert Baer wrote: >>> You can permanently destroy a PicKit 2 programming pod in an easy >>> un-documented manner. >>> 1) Tie one or more pins of a PIC MCU to ground; it does not help to >>> have MCU program use the pin(s) as inputs. >>> 2) Program then power up the MCU with the PicKit 2; you may need to >>> do power down and power up a few times. >>> ZZZZzzzzzaaaaaa:P:! No Poof, No Frap, No Zap; it just gets killed. >>> As far as i can tell the USP port is not damaged; my 1Gbyte stick >>> still reads OK. >> >> Do you know what exactly got fried? >> From your description it appears as though the only overload path >> could be if the programmed micro sets one of those grounded pins to >> a positive output after it's programmed. That doesn't seem like it >> would be enough to destroy the PICkit2 to me. You sure something >> else funny isn't going on? >>> And the damn pods are not cheap. >> >> Err, yes they are, at $35 it's one of the cheapest official >> programmers on the market for any micro. >> >> Dave. >> > The program definitely sets the (offending?) pins to input - the > state of most pins of MCUs are unknown and random until the MCU > program sets their state. That is not so with PICs. The I/O pins have a known state at power-up. The TRIS registers for all the ports default to "1" (input mode). Dave. -- ================================================ Check out my Electronics Engineering Video Blog & Podcast: http://www.eevblog.com
From: E on 15 Sep 2009 09:05 >> >> Have you tried updating it (tools ->Download Pickit2 Operating System) >> I have noticed it tends to lose its operating system if mishandled. > No, but i think that i cannot do that as i fully expect the file to be > over a few megs in size (am on dial-up). Megabytes on a pic? Its actually 27 kB zipped from microchip website
From: ehsjr on 15 Sep 2009 22:07 Robert Baer wrote: > Jan Panteltje wrote: > >> On a sunny day (Sun, 13 Sep 2009 21:07:10 -0700) it happened Robert Baer >> <robertbaer(a)localnet.com> wrote in >> <V7ednUh1WdnzXDDXnZ2dnUVZ_qSdnZ2d(a)posted.localnet>: >> >>> You can permanently destroy a PicKit 2 programming pod in an easy >>> un-documented manner. >>> 1) Tie one or more pins of a PIC MCU to ground; it does not help to >>> have MCU program use the pin(s) as inputs. >>> 2) Program then power up the MCU with the PicKit 2; you may need to >>> do power down and power up a few times. >>> ZZZZzzzzzaaaaaa:P:! No Poof, No Frap, No Zap; it just gets killed. >>> As far as i can tell the USP port is not damaged; my 1Gbyte stick >>> still reads OK. >>> >>> And the damn pods are not cheap. >> >> >> I am still using this one, wrote software for it to support every PIC >> I needed so far: >> http://www.covingtoninnovations.com/noppp/ >> Blow up as many as you want, less then 1$ part count. >> > Nice. But..using unsupported PIC parts and have a fast computer - so i > will pass on the NOPPP. > That site referred to Dontronics which has 4 programmers; all of them > are MUCH more expensive. > Maybe you can build your own - don't give up on that idea too soon. If you don't like the NOPP, there's plenty more. Here's one example: http://www.rentron.com/Myke4.htm That's for a serial port. For USB try http://www.mcuhobby.com/articles.php?article_id=7 At least reading about it is free. Building a programmer might save you some $ so it is worth considering. Ed
From: Robert Baer on 16 Sep 2009 02:25
David L. Jones wrote: > Robert Baer wrote: >> David L. Jones wrote: >>> Frank Buss wrote: >>>> David L. Jones wrote: >>>> >>>>> Robert Baer wrote: >>>>>> You can permanently destroy a PicKit 2 programming pod in an >>>>>> easy un-documented manner. >>>>>> 1) Tie one or more pins of a PIC MCU to ground; it does not help >>>>>> to have MCU program use the pin(s) as inputs. >>>>>> 2) Program then power up the MCU with the PicKit 2; you may need >>>>>> to do power down and power up a few times. >>>>>> ZZZZzzzzzaaaaaa:P:! No Poof, No Frap, No Zap; it just gets >>>>>> killed. As far as i can tell the USP port is not damaged; my >>>>>> 1Gbyte stick still reads OK. >>>> I have no such problems with this test setup: >>>> >>>> http://www.frank-buss.de/pic18f2550/index.html >>>> >>>> The PIC is always powered from external power in my test setup. But >>>> I noticed that the PicKit pulls VDD to low, if disabled, which was >>>> not much of a problem, because of my current limited power supply, >>>> but I think this could destroy the prorgammer. >>> It can only pull VDD low with a 1K in series, so that isn't going to >>> destroy the programmer. >>> www.modtronix.com/products/prog/pickit2/pickit2%20datasheet.pdf >>> >>>>> Err, yes they are, at $35 it's one of the cheapest official >>>>> programmers on the market for any micro. >>>> There are some other programmers within the same price range: >>>> >>>> http://search.digikey.com/scripts/DkSearch/dksus.dll?keywords=428-2021-ND >>>> http://search.digikey.com/scripts/DkSearch/dksus.dll?keywords=336-1182-ND >>>> >>>> But you are right, there are more expensive ones, but then usually >>>> with in-circuit debugging support etc. >>> The PICkit2 has in-circuit debugging capability, stand-alone field >>> programming support, and can power your circuit under test with any >>> voltage from 2.8V to 5V. And as a bonus can be used as a 4 logic >>> analyser and serial protocol analyser too. Pretty good value for >>> money! Dave. >>> >> There was NO (1K) "protection" resistor (8 lines) from MCU to >> ground; at worst 2 pins were shorted. > > Huh? > I'm refering to Frank comment about the PICkit2 circuit and it's ability to > pull the VDD pin LOW. > According to the schematic for the PICkit2 it's got a 1K series resistor in > there for that. > > Dave. > There is an *actual* (and correct) schematic for the PicKit-2 programming pod? Where, oh where pray tell? |