Forum Discussion
Altera_Forum
Honored Contributor
11 years ago --- 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.