Custom DE0 university board design (How to make the USB working?)

Hi Intel Forum users,

I have built a custom PCB for a project at the university to have an on board FPGA. This enables us to do the DSP on the FPGA and reprogram parameters etc. I have used the DE0 documentation included as a reference design and this is exactly taken from the schematics on the implemented PCB.

However when debugging no USB communication between laptop and PCB could be found. Both the USBP and USBM are constantly grounded and the 6MHz signal between the FT245BL (USB chip) and the EPM240T100 is also not found. The 24MHz clock of the crystal oscillator is verified.

I was wondering if someone here ever worked on the USB port communication and knows where the problem could be? I highly suspect that a certain program has to be uploaded to the FT245BL and EPM240T100 to be in the right settings.

For verification I use a measurement setup with the PCB and the DE0 FPGA, and the DE0 FPGA board does connect and communicate with the USB port.

Best regards,

Gerrit Kas