STM32U083CCT6 Bare-Metal USB Initialization

[tensaisakuragi06]

After i finish my setups according to STM32U0 Bare-Metal USB workshop video. When i compile and load he program to my PCB adn then connect my pcb to PC via USB cable; at the device manager connection seems undefined like the picture below. It says that Unknow USB Device. Does anybody face like this kind of problem?

 

[FBL]

Hi ​@tensaisakuragi06 

Did you refer to our reference boards? Check the hardware wiring  D+/D−, VBUS..

[tensaisakuragi06]

CubeMX guide me about that. I dont think its about the wiring Because i measure around 3.15V on D+ and 0.2V on D- of USB pins. And its interrupt mechanism also work. I test its initializations etc with debug. But i can not solve this windows Unknow USB device warning. I also can not see any parameters ın CubeMX interface about Vsense(For 32U083CCT6 MCU).

[tensaisakuragi06]

By the way i directly tie 5V of USB socket to my 5V rail. But know there is no 5V exist, i run MCU and its peripherals with 3.6V battery powered( 3.6V > 3.3V LDO > MCU and Peripherals ).

[Shirley.Ye]

it seems enumeration fails before Windows can identify the device correctly. check the Clock configuration and the power supply

 

[tensaisakuragi06]

My clock source for USB is HSI 48Mhz. At software side e enable Power Supply. And when i measure Vddusb, fixed 3.32V comes.

[tensaisakuragi06]

After continuous countless tries, i realize something and b.t.w i still does not know the reason why it fails and why is successfully seen by Windows. The first thing i want to explain is: I use my PC case front panel USB ports for this application for first tries as seen in 1st picture.

Front Case USB connection (I did not try blue colored 3.0 connection).

And second and in my opinion my successfull tries, i used USB port directly on motherboard like in second picture:

Motherboard USB connection(succesfull connection)

And when i use motherboard connection, i get successfull connection at the list of:

I still do not know why it was listed in “Bağlantı noktaları(COM ve LPT)” instead of:

And when i power my pcb with battery( 3.6V SAFT LS14500 Li-SOCl2 battery), i never successfully built usb connection. I have to do it with battery but i have no solution for it for now.