When reverse engineering the bootloader, i see interessing parts of code, not readable or explained in the manuals,
i think that is really possible, yes.

But I have not tried it, because avoiding the result of loosing my PLCC52 part in the developer board.


I use an already made JTAG interface on 3.3V for Altera Devices,
if you read the PDF document you can see it is all single
voltage, XTAL pin, RESET and T0 en T1 pin to do the job.
Not a heavy job. ;)