Hello, I'm completely new to JTAG and wanted to see if I was on the right track here. I was looking at buying one of these: http://www.ebay.com/itm/NEW-XILINX-USB-CABLE-DOWNLOADER-PLATFORM-JTAG-DONGLE-/260812659422?pt=LH_DefaultDomain_0&hash=item3cb9a55ade I have a Papilio Pro that I run a (slightly) modified ZPUino on but the core is the same. The main difference is I don't use the UART to program it in the same way ZPUino does, basically I have custom boot loader code. From what I can gather from searching the web and this site it seems easy enough to use IMPACT to program a bit file and it seems I can debug code running on the ZPUino with this as well based on my understanding of how "zpuino_debug_core.vhd" and "zpuino_debug_jtag.vhd" work. So here is where I am at: Solder a header onto the open JTAG slots on the board Put the FT2232 into High-Z mode (does the second channel used for the UART still work in this case?) Program an updated bit file that incorporates the zpuino_debug_jtag(this is the TAP, correct?) with IMPACT And then I'm not sure where to go from there, is there a program that will let me use GDB(zpu-elf-gdb) with this configuration to step through code? Is this what OpenOCD does and if so can I use it with the ZPUino core? Is there anything else I need to do this? Any insight would be much appreciated as to how/if you guys are doing this kind of thing. Thank so much.