iceman

Hello, I'm trying to connect a JTAG-HS3 (Rev.A) with a Spartan-7 (XC7S6-1FTGB196C) using Vivado Lab Edition 2021.2 but Vivado keeps telling me that I should check cable connectivity and Spartan-7 cannot be found.I tried two HS3 to be sure it's not damaged. I tried speed down to 125kHz. A Xilinx platform cable USB II works fine with same cable (HS3 needs a extra pin header since HS3 and platform cable have different genders). VREF is at 3V3. TCK, TMS, TDI and TDO have all a 10k pull up. The levels of TCK and TDI look fine during startup (3V3) but drop down to 1V after a short while. Spartan-7's flash hasn't been written yet. Any idea what's wrong here? What pull ups/downs are needed by HS3? Thanks a lot for all your help in advance!