Invalid JTAG configuration - Invalid JTAG configuration Hi Quartus 24.1 standard edition & Windows 11 I tried a new usb blaster ii today and ran into a problem. The computer recognized the blaster ii and installed drivers automatically. I was able to use the programmer to program the Max 10 device, so I know the jtag chain is working. However, I have a message that I have an invalid JTAG configuration in signal tap. The problem seems to be related to selecting hardware in the jtag chain configuration. I selected usb blaster ii in the pulldown box and close the window (attached). I then try to run signal tap and initially it says acquisition in progress but then says invalid JTAG configuration (attached). When I go back to the JTAG Chain Configuration, the pull-down selector says no hardware. I also see that the signal tap status says “instance not found”. I can reselect usb blaster ii but it always goes back to No hardware after I close the hardware setup window. I updated the usb blaster manually but that didn’t help. I checked that the jtag status and server info using the command line and they look to be running. I have deleted the db directory and did a full recompilation without any success. I finally went back and changed the Hardware Frequency to 1MHHz and was able to run. I even managed to change the Hardware frequency back up 26MHz after I got it to run. I was running all day until I changed the name of the .stp file and then it stopped working till I changed the Hardware Frequency back to 1MHz Any idea what is going on? Any help is appreciated Replies: Re: Invalid JTAG configuration Hi, I’m glad that your question has been addressed, I now transition this thread to community support. If you have a new question, feel free to open a new thread to get the support from Altera Technical Support. Otherwise, the community users will continue to help you on this thread. Thank you. Replies: Re: Invalid JTAG configuration Hi Frank, I am able to get it to work reliably at 16MHz Thanks Replies: Re: Invalid JTAG configuration Hi, sounds like your hardware doesn't support highest JTAG speed. Did you try a moderate setting like 6 MHz (original USB Blaster) or 12 - 20 MHz. Regards Frank