Strange issue with bypass cap and AVRISPMKII

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I am having a strange issue with the AVRISPMKII programmer, I added a 33uF bypass cap between VCC and GND pins on an ATMega88PA for better stability(as I'm driving an electric motor and everything is powered by same source) and the AVRISPMKII says there is no power on the target now. I check with a multi-meter and I am reading 5v out of the regulator, 5v directly accross the pins of the cap(which are soldered directly to one power and one gnd pin on the ATMega). Any ideas as to why this is happening? About the only thing I can think of is that something the hardware of the programmer is no longer able to accurately read the target voltage with 33uF of capacitance accross VCC and GND, although I can't logically think of why. Its a standard low ESR tantalum cap. The 5v regular already has 22uf bypass cap as recommended by the data sheet to prevent oscillation, so I don't see how adding another tantalum cap would cause an issue...I must be missing something

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Might be an obvious question, but the problem goes away when you remove the cap right? I.e. you can confirm that it's really only the capacitor that's causing trouble

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Sounds like it isn't the cap.. check the cord.

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Are you sure the the Cap is across the correct pins and the right way around ? ('though I suspect if it was backwards you would have found out by now !). Maybe there's a problem with your power supply being unable to provide enough oomph to get over the power on current surge ? (I know that's unlikely for just an additional 33uF). I suppose that if there's a lot of resistance in the cable then it would take a while for the power supply to reach the full voltage at the IC, if it's read before that time it may flag undervoltage ?

I agree with Basil remove the cap and see if everything works. Then try adding another cap just to check that the first one doesn't have some weird leakage problem. It's an interesting problem, please let us know how you fix it.

<º))))><

I am only one lab accident away from becoming a super villain.

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Does the MKII work on another target board? If not then the connector on the end of the programming cable may need re-seating. This is a common issue with that flat cable connector.

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I removed the cap, same problem. Coincidence mislead me, after removing the connector one of the leads came right off, so I believe there was no ground connection(pin6), which would certainly cause no voltage to be detected. Thanks for the help guys, always appreciated.

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*gives himself Boy Scout genius-badge*