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This is mostly a Microchip centric question. I'm very new to Microchip world. So any info beyond my questions is most certainly helpful to me...

I purchased one of these demo/break-out boards from Microchip:

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en024149

I tried plugging in the supplied dsPIC33 module and programming by connecting to the header my PicKit2 programmer. I wired up one wire for the Vss, one for the Vdd, one for the PGD, and one for the PGC lines.

The PicKit2 programming software and MPLAB both complain that the Vdd voltage is measuring zero (as if to say the voltage supply has a short?). Then I noticed the PicKit2 getting very hot!

I quickly unplugged it, let it cool down, and verified that it still worked on other circuits I have & it did.

This particular demo board has a jumper marked 5v and according to the manual, I can power the board with 5v or 9v. So I pulled the jumper and put 9v on the board and reconnected my PicKit2 and still got same results.

Questions:

  1. Do all the Vss lines need to be wired to ground? I only wired one Vss to the PicKit2
  2. Do all the Vdd lines need to be connected to the 3/5v supply line? I only had one.
  3. Is it even possible to program via this demo board, a socketed dsPIC33 chip (see link above).

I have other dsPIC33s I can program external to this demo board. They are mounted on a circuit board that was not designed by me. This board has a header I can connect the PicKit2 directly too. I don't have a schematic for the board either so I'm not sure if the Vss and Vdd lines are tied together or not; I just know I can programm the same dsPIC33 chip on this board with my PicKit2.

I'm considering purchasing their MPALB ICD 3 programmer? What benefits does the MPLAB ICD 3 programmer offer over the PicKit2 programmer?

My goal is to simply be able to program socketed dsPIC33 Microchip micros and have access via header break-out to various signals for quick prototyping.

Based on the comments so far, come clarifications:

  1. I forgot to mention above that I did have the MCLR pin wired as well.

  2. I should add, that I checked, double checked, & triple checked that non of my jumpers were touching, chip was oriented in the socket correctly (pin-1 aligned with PCB pin-1 and checked written documentation for the board), and jumper wires were on the correct pins. Why it got so hot is puzzeling me. I will look to connect a RJ11 type jack to the J3 port into the PicKit2 to see if that makes a difference but have my doubts. I used purchased jumper wires with molded ends for connecting to headers so, for example, pins 11 & 12 are the Vss and Vdd pins, there is no way the wires could have been touching each other. Their header connectors are insulated and such...

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  • \$\begingroup\$ Do you power the board while programming? \$\endgroup\$
    – Tom
    Oct 20, 2011 at 22:45
  • \$\begingroup\$ @Tom: At first no I did not. I left the 5v jumper in place thinking that meant I could use the 5v from the PicKit2. When that did not work, I hooked up a 9v DC source and removed the jumper and tried again with the PicKit2 and it still did not work. \$\endgroup\$
    – Eric M
    Oct 21, 2011 at 1:05

4 Answers 4

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If the PICkit 2 is getting hot you must have a wiring error. You need to wire it up to the ICD 3 connector, J3, the connections are identical, or you can buy or make a plug-in adapter that allows it to be used with the ICD 3 connector. J3 includes MCLR which must be connected.

I have two ICD 3s and a PICkit 2. The former is a lot faster, and supports the latest devices.

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  • \$\begingroup\$ yea, sorry, forgot to mention that I did also wire the MCLR pin too. \$\endgroup\$
    – Eric M
    Oct 20, 2011 at 18:11
  • \$\begingroup\$ well, as it turned out, the socketed chip was installed at the factory 180 degrees rotated. It actually came from Microchip that way. Unreal. They evidentially don't QC the as-built product before shipping them out. So, ultimately, it was a wiring problem but kudos to Kellenjb's response as it was VERY helpful for a new guy! Thank you! \$\endgroup\$
    – Eric M
    Nov 5, 2011 at 2:18
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Here is sort of a list of things you can run through to see if you can get your problem fixed.

The PicKit2 is not ideal to be powering a device off of. It can provide enough current for a low power device, but as a rule of thumb, don't try to power your board with your programmer unless you know it can provide enough current. I haven't looked at the specifics of the board you mention, but it should be fine. When you are self powering your board, you need to make sure that your MPLAB settings are configured to not supply power.

This particular board has a programmer connector that is easiest used by an ICD. See FIGURE 2-11 in this document. It sounds like you are just wiring around this, which is fine, but make sure you get all of the lines in the right place. Accidentally shorting some wires or connecting them to the wrong place are probably the most common errors I have seen with results like this. You also need to make sure your MCLR line is connected to the programmer.

To go through your list of questions:

  1. You should only need 1 Vss line wired to ground. The board itself should have a ground plan that all of the Vss lines are connected to.
  2. Same thing as #1 for power
  3. It should be possible.

I'm considering purchasing their MPALB ICD 3 programmer? What benefits does the MPLAB ICD 3 programmer offer over the PicKit2 programmer?

This question might help you some.

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I wired up one wire for the Vss, one for the Vdd, one for the PGD, and one for the PGC lines.

You are missing the MCLR, or sometimes called Vpp, line. For PIC programming, you need a total of 5 connections between the programmer and the target chip.

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  • \$\begingroup\$ I wouldn't think this in and of itself would cause the PICkit to get hot. \$\endgroup\$
    – Kellenjb
    Oct 20, 2011 at 17:15
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    \$\begingroup\$ @Kellenjb: True, but not hooking up MCLR is definitely wrong, so I'd start with fixing that and see where you're now at. \$\endgroup\$ Oct 20, 2011 at 17:29
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    \$\begingroup\$ I'm sorry, I left that detail out in my original post. I did wire the MCLR up too. I had a total of 5 jumper wires connected from the PicKit2 to the header breakout of the demo board. I figured that if I removed the 5v jumper and put 9v on the board, this would provide necessary power that possibly the PicKit2 (via USB) is not able to drive. \$\endgroup\$
    – Eric M
    Oct 20, 2011 at 18:11
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I'm considering purchasing their MPLAB ICD 3 programmer? What benefits does the MPLAB ICD 3 programmer offer over the PicKit2 programmer?

One of the advantages of the ICD 3 is that Microchip will replace it if anything goes wrong. I was about to say, "with no questions asked", but they do have you fill out a form indicating what you think is wrong with it.

Anyhow I recently had a problem with an ICD 3 I bought two years ago. I filled out the form and they sent me a new ICD 3. I then had to ship the old one back. Other than the return postage, there was no cost to me.

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  • \$\begingroup\$ wow, I like the sound of that! I'm considering the combo of the ICD3 programmer and their Explorer 16 board. Seems a little pricey but now that you mention this return/warranty policy this may not be so bad after all! Thank you! \$\endgroup\$
    – Eric M
    Oct 20, 2011 at 18:14

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