debugWire + AVR One debugging/programming confusion

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I'm using an AVR One to program/debug an ATTiny85 board running on the Tiny's internal oscillator. This is a board I developed a few months ago, programmed/debugged, put aside and am doing some more debugging on now.

When I first fired up AS 5 on the AVR One today it asked if I wanted it to set the DWEN bit, so I said sure, cycled the power, and did some debugging. When I tried to program some changes to the code, I can't switch to ISP mode. When I try, I get a warning, "Unable to enter programming mode" and I can't read or program anything. This is after I "Stop Debugging" which I thought reset the DWEN for me. Maybe I'm leaving out a step (likely, if I don't use this stuff at least once a week, which I don't, I'm afraid).

What am I doing wrong? Thanks.

PS - I also have an AVRISP mkII that can't access the device either, so I'm assuming the DWEN bit isn't being reset.

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Quote:

after I "Stop Debugging" which I thought reset the DWEN for me.
It does as long as you follow all directions and all six ISP wires are in place.

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So, after I stop debugging, I should be able to go to Device Programming and read/write/verify my code, right? I have the ISP clock dialed way down to 64 kHz, I cycle the power, and Interface is set to ISP (the only option offered), but I still can't read or write. No cap on the reset line.

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No. You do your debugging. When finished you choose "Disable debugWIRE and Close" from the Debug Menu.

Don't ever try fiddling with the DWEN fuse yourself.

David.