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Altera_Forum's avatar
Altera_Forum
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18 years ago

Cyclone 3 board acting up.

Hi,

My Cyclone 3 board has been acting up. Quartus does not detected the USB Blaster Interface when I try to program it. I connected a DE2 which it detects.

The Cyclone LEDs count like they are supposed to. When I probe some points like the JP8 pin, Windows tells me briefly that the USB Device has malfunctioned, so Windows can see that a board is connected and it is being probed.

Any ideas how I should troubleshoot this? I have a paper deadline coming up, and there is no way I can make all the lab assignments on the DE2 now.

Thanks,

~E.

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    What are you probing with? Make sure that you are using a high impedance probe (10 Mohms or more). I've seen windows lose usb devices like that due to shorts or loading pins (aka making Vcc dip) . Losing the USB device while probing is not a good thing.