Can't select USB-Blaster in SignalTap

[Altera_Forum]

Hey there, 

 i'm using Quartus II 64bit 12.1 to program a Cyclone IV. Everything works fine, except sometimes i can't use SignalTap. I've already googled some time and used the forum search. Now here's my problem:  If i want to use SignalTap sometimes it works, sometimes not. Problem is: i can't select the proper USB-Blaster in case of some other devices connected to USB, using the same FTDI (communication to a DSP). So this means, in Quartus itself i'm using USB-Blaster[USB-0] which works fine, then after switching to SignalTap i can't select USB-Blaster[USB-0]. The only possible hardware to select is - maybe - USB-Blaster[USB-2] which is definetly not the Blaster I used to programm the Cyclone. I'm sure that it's a kind of driver-conflict (i'm sure about that, because if I use a second PC for Quartus and SignalTap everything works fine), but i need to use all the USB-devices the same time at one computer.  So has anyone an idea how to deal with this problem?! (Sometimes the SignalTap connection works.. but i can't say why:D )  Thanks!

[Altera_Forum]

Do you have multiple USB blasters connected to your computer? Or are you saying that some other FTDI device is mistaken as your USB blaster? Sometimes the USB blaster will changed port number if re-plugged. What does jtagconfig report?

[Altera_Forum]

One of the other FTDIs is mistaken as USB-Blaster. How can i run jtagconfig?

[Altera_Forum]

--- Quote Start ---  Hey there,  i'm using Quartus II 64bit 12.1 to program a Cyclone IV. Everything works fine, except sometimes i can't use SignalTap. I've already googled some time and used the forum search. Now here's my problem:  If i want to use SignalTap sometimes it works, sometimes not. Problem is: i can't select the proper USB-Blaster in case of some other devices connected to USB, using the same FTDI (communication to a DSP). So this means, in Quartus itself i'm using USB-Blaster[USB-0] which works fine, then after switching to SignalTap i can't select USB-Blaster[USB-0]. The only possible hardware to select is - maybe - USB-Blaster[USB-2] which is definetly not the Blaster I used to programm the Cyclone. I'm sure that it's a kind of driver-conflict (i'm sure about that, because if I use a second PC for Quartus and SignalTap everything works fine), but i need to use all the USB-devices the same time at one computer.  So has anyone an idea how to deal with this problem?! (Sometimes the SignalTap connection works.. but i can't say why:D )  Thanks!  --- Quote End ---    Boy, this sounds familiar. I know I've encountered this problem before. When you use SignalTap do you by any chance ever have the Quartus II programmer window open as well? If I remember correctly, the programmer and SignalTap cannot share a USB Blaster. You have to close one program before opening the other. If that's what's going on, remember that you can download a .sof file to the target FPGA within SignalTap. You don't need the programmer to do that.

[Altera_Forum]

--- Quote Start ---  One of the other FTDIs is mistaken as USB-Blaster. How can i run jtagconfig?  --- Quote End ---    If your PATH is set up correctly you should be able to just type "jtagconfig" in your shell/command window.

[Altera_Forum]

--- Quote Start ---  Boy, this sounds familiar. I know I've encountered this problem before. When you use SignalTap do you by any chance ever have the Quartus II programmer window open as well? If I remember correctly, the programmer and SignalTap cannot share a USB Blaster. You have to close one program before opening the other. If that's what's going on, remember that you can download a .sof file to the target FPGA within SignalTap. You don't need the programmer to do that.  --- Quote End ---   This could be the problem. Usually i programmed the device using the Quartus II programmer (but i closed it afterwards..) and then tried to connect via SignalTap. I'll keep an eye on it. Thanks!    --- Quote Start ---  If your PATH is set up correctly you should be able to just type "jtagconfig" in your shell/command window.  --- Quote End ---   Ok, i used jtagconfig, but there was no other device detected except the USB_Blaster. I'll have a look on jtagconfig, the next time my problem appers. Thanks!