What could be wrong?
Have a design using the TUSB9261 that will not enumerate when connected to PC with USB 2.0 cable. 3.3V and 1.1V supplies ramp up simultaneously so that 1.1V is up prior to 3.3V. Reset deasserts 12 ms later. Clocking at 25MHz using a 1.8V clock oscillator with FREQ SEL0 pin pulled to 3.3V and FREQ SEL1 pin tied low. Have opened the SPI data in line just in case. And there is activity on the SPI clock line - CS activates. But no activity is seen on the DP, DM USB lines ever.
Windows does not see it.
USB3.0 lines are open.
GPIO3 is pulled high.
Tried tying GPIO4 high - didn't help.
USB_VBUS pin has ~0.5V when plugged in.
Have read data sheets, app notes and looked at EVM manual - must have missed something.
Anyone have insight on this?
Your configuration seems correct, can you share your schematics for analysis?
Are you using a TUSB9261 evaluation module?
If you don't want to post your sch here you can sent it to firstname.lastname@example.org
Thanks for your help, Elias.
We found some resistors placed that shouldn't have been shorting the SSUSB signals to ground.
Removing them allowed the flash burner and windows to see the device.
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