New Contributor
New ContributorWe have the exact same problem. You plug in the blaster and sometimes it works (shows up as USB-BlasterII) and sometimes it doesn't work at random (shows up as USB-Blaster variant). We use the Quartus Prime Programmer included with Quartus Prime Pro 23.2. Upgrading to a new quartus version is not trivial for us, since this is the last version that still supports Nios II, which we require.
We have never identified any pattern as to make sure it doesn't happen, we usually just disconnect and reconnect and/or restart the PC until it shows up correctly.
It will not work for programming if it shows up as "USB-Blaster variant"
Of course we have the driver installed, it works sometimes.
I'm fairly sure it's only a Windows 11 problem, as I had Windows 10 personal machine for a long time and never had the issue until I upgraded. Our other machines are all Windows 11.
New ContributorI found a workaround in another thread about this issue here: [USB-Blaster] Detected as "USB-Blaster Variant" on SLES12 – Causing Detection Issues | Altera Community - 319603
The pattern is that the device shows up incorrectly as "USB blaster variant" if it got plugged in while "jtagserver.exe" is running in the background. In task manager it is called Background Processes > Intel Quartus Prime Pro Edition Software (jtagserver.exe).
**Kill this process before plugging in the device**, then open Programmer. You hear the Windows device connect sound when the software opens, and then it shows up correctly as "USB-BlasterII".
