[avr-gcc-list] Intermittent connections with clone JTAG ICE

[Mike Young]

I bought a clone JTAG ICE from Microcontroller Pros 
(http://microcontrollershop.com/product_info.php?products_id=1106&osCsid=b6732e459ab35fe55dc115a10aec8f52) 
thinking to play around with the Butterfly. AVR Studio 4.12 has trouble 
connecting to it, and once connected, often drops the connection. Avarice 
doesn't see the device at all. Sometimes, forcing a reset on the Butterfly 
allows AVR Studio to connect briefly. "Briefly" means a few minutes of 
debugging, uploading a new image to flash, or reading or setting fuse bits. 
Sometimes, it resets the device and allows connections by unplugging and 
replugging the JTAG cable from the Butterfly. Most often, I remove the 
battery from the Butterfly to force a reset; this helps the connection most 
of the time.

Being new to AVR and their tools, I'm not sure what my expectations should 
be. Is this a properly functioning device? Can the software be doing 
something to make it unstable? (The problems seem identical with the base 
Butterfly code, the ported GCC Butterfly code, and my own simple 
hello-world.) Are there fuse-bits that can help/destabilize connection?

Thanks.
Mike.