I bought AVR JTAG ICE version 2 programmator. I already have an ATXMEGA128A1 on my dev board. Now, as the board is expensive and from school, I wouldn't like to fry it. The programmator works at 5V while my microcontroller at 3.3V. My mentor says that connecting these two will cause friage if not on the same voltage level.
Other than that, in a documentation about some general JTAG AVR programmator, it said that the programmator will adjust its power supply according to the target. I'm not sure about that. I measured the voltage on the programmator's pins and it said 5V. On the dev board, it said 3.3V.
So do I first have to unplug the programmator's USB, plug in dev board's USB, plug programmator into dev board and then plug the programmator's USB? I feel very uncomfortable about this. I have only one attempt to do this resulting in success or friage. I'm sure you guys have been there and had programmators so surely you somehow solved the problem. If you know how, I would like you to tell me.