Hello Dave,
I have finished the pdf that you gave but not quite get it.
That's why I am trying to use Virtual Jtag starting with a simple verilog design which is a 4 bit counter.
I'm starting by using megawizard manager. I don't quite understand at page 4 of virtual jtag megawizard. What is actually stimulus? I think this is where we define the shifting operation(not sure). How should we know how much delay needed for the stimulus?
I also a bit confuse of the diagram block of virtual jtag that shows during megawizard.
Why TDO and ir_out are put at the left side and tck, tdi, ir_in are located at the right side? I think it should be in contrary because TDI(Test data input), TCK(Test clock) and IR_in are the input of the VJI(virtual jtag).
I think I am asking too much. Hehehe... :) Sorry.
By the way, how about the progress of your tutorial?
Thank you so much