Pickit2 VDD seems to be fixed at 4,8V

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patroclus

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Hello,

I can read and write PIC24H while pickit powers the device, but reciently I realized that VDD voltage isn't correct. If I try to calibrate pickit2, I measure 4,8V, and once I enter that value (instead of the default 4V that appear in the dialog window's text box) the software complains, and I get an error. Basically it is imposible to calibrate. Even if I manually change the supply voltage from the main window, I always measure 4,8V... programming is OK, but I just cannot debug , even setting correctly the EMU pins in the configuration bits (MPLAB IDE complains about voltage, even if I supply voltage externally and tell MPLAB to always use target power).

Any help?

thank you
 
Don't think so. My laptop's USB ports work fine with just everything, and I've been using it for three years.
What I find strange about this is that it happends without connecting pickit to any circuit, which could be the source of the problem...
 
I have two pickit2 and have never had what your taking about happen but two times one the usb power went out on my computer. My mouse worked find but I couldn't use the pickit2 Ans two I burnt up a pic32 using the auto power function.
newer picikt2 software fixed a lot of bugs with the pic 24h
PICkit 2 V2.61.00
Device File V1.61.00
 
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I'll try with another computer and see what happends. Couldn't the problem be with my pickit2? It is a clone, and it may not be working properly... I don't know. But I don't have another one to try it out.
 
patroclus said:
I'll try with another computer and see what happends. Couldn't the problem be with my pickit2? It is a clone, and it may not be working properly... I don't know. But I don't have another one to try it out.
Click to expand...

If it's a clone then it's NOT a PICKit2 - many clones leave out the variable Vdd facility.
 
Nigel Goodwin said:
If it's a clone then it's NOT a PICKit2 - many clones leave out the variable Vdd facility.
Click to expand...

That is a whole new ball game I've made a bunch of clones. And i've tested some that over loaded the usb and windows xp
remembers things like that so when you plug in old hoss with id usbxxxxxx i'm taking your power away you hurt me last time. I 've pop up usb power management on window xp making clones the PICkit Serial Analyzer


Most clones can't set power they leave that part to save money
 
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The 5V regulated voltage from the USB port eventually leads to the PC PSU. It is understandable that the voltage isn't exactly 5V, I don't think that should be expected of it. However, my PK2 voltage output is around 4.8V as well, so either this is a coincidence or otherwise we both have PSUs that are slightly off.
 
EN0, but can you set pickit2 to output, let's say, 3,3 V or 4 V or whaterever you like, from the stand-alone application ?
 
Here some real life pictures the clone can't set the voltage the real pickit2 can
The 2.6 volts is the pickt2 set as low as it can 4.8 is as high as it gets

the 4.9 is the clone it can't set lower there no real voltage control on the clone
 

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Thank you very much. I'll try to get an original pickit2...
So far, I still find weird that I cannot enter debug mode with PIC24 even though I set "always use target power" in options, and I use an external power supply at 3,5V. PIC runs fine, and it also can be programed fine (even inside MPLAB IDE) but not debug...
 
It takes more then the correct voltage for debug to work. The program has be built correctly. Correct linker info etc.
 
True PICkit 2s from Microchip have circuitry to vary the output voltage. Many clones lack the circuitry to do this, and will be fixed at whatever voltage the USB port provides - somewhere between 4.5 and 5 volts isn't surprising. And a hub may provide a different voltage then a USB port on the PC.

Even if the clone lacks the circuitry to change the voltage, it will still show up as an option in the GUI but it won't make any difference.

With a Microchip PICKit 2, you can calibrate the USB voltage. This won't (I believe) output more than the USB voltage, but anything less than that will be calibrated.
 
patroclus said:
EN0, but can you set pickit2 to output, let's say, 3,3 V or 4 V or whaterever you like, from the stand-alone application ?
Click to expand...

Yes, that is possible. One way to do it is to program your PIC through the PICKit2 software, in which you select the voltage output there.
 
Then you get done playing around read this



And then read this https://www.electro-tech-online.com/attachments/pickit2-user-guide-51553e-pdf.46259/

Starting on page 35 down to 85
 
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Now I always use target power. I don't supply any power with pickit2. Programming fine.

I correctly set the configuration bits for the used debug pins, and MPLAB still complains about target power. It reads 0V. Even though it works for programming (it detects 3,3V target power). I don't know if this is because it is a clone, or what.

My oscillator setting is internal FRC w/PLL, and primary oscilator disabled... also, I realized that when trying to debug, MPLAB IDE requires reprogramming (even if I make no changes). Then, entering debug mode fails. But this is interesting,... PIC24 does not boot anymore (it just doesn't do anything). I need to reprogram it, and then it boots again. Why? Well, everything is the same except one bit in the FICD config register (which is changed when trying programming to enter debug mode). Until I set it back to the previous value, PIC does not start working again. The bit is BKBUG. Any clue?
 
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