Dead Dragon?

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Hi All,

I have a Dragon showing the following symptoms:

1) The ATMEGA2560 on the board gets distinctly warm/hot to the touch. I normally run the Dragon inside its box, so I don't know if this is normal.

2) In AVR studio I can read and write the ISP frequency, and can read back the target voltage (correctly).

3) The LEDs on the Dragon seem to blink as I would expect, to indicate USB activity and connection to AVR Studio.

4) I have a whole bunch of mega48/88/128/328 chips, some of which may have debugWire switched on. I can't debug (using DebugWire) or read the signature (using ISP) on any of them.

5) When attempting a debugWire connection, there is no evidence of any activity on the RESET/debugWire pin (looking at it on a scope).

I conclude that some part of the Dragon is dead, but I would be keen to try to resuscitate it if anyone has had similar experience or has any ideas.

Thanks in advance.

Christopher Hicks
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cmhicks wrote:

I have a Dragon showing the following symptoms:
For what it's worth, I am now sure that the ISP/debugWire part of this Dragon has died. Thankfully the HVPP bit still seems to work.

The debugging routine (program the part, lever it out of the programmer, install in the target board, bend a pin, swear, pull it out, straighten the pin, look which LEDs light up when, pull the chip, change the code, push the chip back into the programmer, bend another pin, swear louder, etc, etc) almost makes me nostalgic...

CH
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Why have you been moving chips?

Presumably you have an ISP header on the target board. So you just connect your 6-pin ribbon.

You can move to debugWire mode with the ribbon in place. And add your extra hardware on the ISP lines.
Once you have finished low level testing, you can load the program using avrdude in debugWire mode.

When done, remove the extra hardware from the ISP lines. Re-enable ISP.

You would only ever program a chip on the Dragon for HVPP.

David.

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I wrote:
I am now sure that the ISP/debugWire part of this Dragon has died. Thankfully the HVPP bit still seems to work.

david.prentice wrote:
Why have you been moving chips?

Does that answer your question?

CH
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