I was about to start hacking on xc3sprog after e-mailing the author and not hearing back, but I was curious if anyone else has done the same. I'm interested in adding programmatic support for the spartan-3 USER1/USER2 instructions, as well as getting it to program my coolrunner-II CPLD and Virtex-4 LX. Before I reinvent the wheel, has anyone else done this?
...Eric