To generate scan_shift clock and edt_clock you need the following pins: test_clock, scan_en, edt_update. You will also need two AND gates. To generate edt_clock AND test_clock with scan_en. To generate shift_clock AND test_clock with inverted edt_update.
There is a section in the Tessent Shell Reference Manual that shows the logic under "add_dft_signals" command description. The manual can be found here: https://supportnet.mentor.com/docs/201611047/docs/htmldocs/mgchelp.htm#context=tshell_ref&
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