Hi.
The programming interface changed from ISP to PDI on XMega controllers. The JTAG MKII can program and debug the XMegas via PDI with a software update, but only the newer hardware revisions seem to have the required hardware support.
I'm not very happy to discard my current hardware and spend 300¤ for another one. So my question is: What are the hardware differences between the older (non-PDI) and the newer (PDI-enabled) revisions?
My guess is that pin 9 (TDI), which is used as PDI_DATA, is input only in the older revisions and bidirectional in the newer ones. So a new driver should do the trick.
SMD rework tools are available.