--- Quote Start --- Can I do test bench for a VHDL design through the JTAG usb cable? If yes, is there a nice tutorial? --- Quote End --- Here's a tutorial that should get you started: http://www.alterawiki.com/wiki/using_the_usb-blaster_as_an_sopc/qsys_avalon-mm_master_tutorial There are Modelsim simulations and Tcl scripts that show you how to implement a simulation testbench, and then test via JTAG. Cheers, Dave