SPI bus to drive the JTAG port, instead of bit-banging the JTAG

clearer and I agree. I understood your verbiage in the first post as convert USB to SPI, then convert SPI to JTAG.

use Eclipse .. to replace the always delightfully surprising SiLabs IDE.

SILABS DEVELOPERS: get the debugger out of the friggin IDE and make it WORK, it is more important that it works than it is that it is in a friggin IDE As long as it does not work, who gives a hoot that is is "delightfully integrated". There seems to be so much more effort on IDEing than on fixing the debugger.

Have you noticed that users of other brands use Keil to compile etc and then load a freestanding ICE? WHY do you insist on doing it differently? If you separated the debugger and left the IDE stuff to Keil (for those poor sods that think they need one) you would actually have the resources to (maybe, just maybe) get the debugger to work. The ONE major advantage SILabs has over many others is the built in debugging, why do you screw up the one advantage SILabs has.

while I, as you see above, totally agree that the SILabs debugger STINKS, I can see you having a lot of fun making the software for debugging SILabs chips under Eclipse.

Erik