I’m implementing a DART-MX8M CPU on a custom board that I designed.
I have problems with the USB ports. Attached image USB1.jpg shows the block diagram of the interfaces.
At the moment, none of the USB interfaces work; Even a simple USB flash disk (USB2.0) put into USB3.0 connector J3 does not work.
- The same CPU, put in the development kit VAR-DT8M, shows that USB is working.
- image USB2.jpg shows the USB3.0 circuit schematics
- I tried to check the electrical signals D+ and D- on the USB connector (J3) upon insertion of the Flash disk in the connector; while I see the D+ line pulled up by the peripheral (the flash disk), the host (the CPU) never responds.
Excluding any electrical issue that I searched for without success, could you see any major issue/error/lack
Should I change some CPU setup/config register?
Can you help me in any way?