Stratix III Development Kit Embedded USB Blaster Problem

The Embedded USB-Blaster will disable itself if there is a cable plugged into the external blaster socket (whether that cable is connected on the USB side or not). This is to protect against two cables trying to drive the JTAG chain at once. Please check that you have unplugged all external blaster cables.

If I remember right then this board has two MAX devices on it - a small max device which runs the USB-Blaster and a large max device which reads the flash and configures the FPGA from it (among other things).

If you have reprogrammed or erased the USB-Blaster max then that cable will not work. You may have bricked your board as a result, so best not to touch that one.

If you have erased the System Controller (large) MAX then the board will no longer configure at startup - you just need to reprogram it to get the board back to life.

If none of this helps then can you cut and paste the error message from `jtagconfig -d` as the exact error message give useful information about the failure.