![Mike on Twitter: "USB-C question: I've seen others pull down CC1 & CC2 through a 5.1K resistor many times but the STM32 BlackPill appears to connect them to each other.? https://t.co/p3RjMr1Bvm" / Mike on Twitter: "USB-C question: I've seen others pull down CC1 & CC2 through a 5.1K resistor many times but the STM32 BlackPill appears to connect them to each other.? https://t.co/p3RjMr1Bvm" /](https://pbs.twimg.com/media/E9zwYWaXIAkEuMf.jpg)
Mike on Twitter: "USB-C question: I've seen others pull down CC1 & CC2 through a 5.1K resistor many times but the STM32 BlackPill appears to connect them to each other.? https://t.co/p3RjMr1Bvm" /
To what voltage should the D+ line be pulled up when designing USB connection in STM32? +5V or +3.3V? All documentation and dev board scematics says it's 3.3V, but it didn't work.
![probably USBD_reenumerate have issue after update · Issue #1029 · stm32duino/Arduino_Core_STM32 · GitHub probably USBD_reenumerate have issue after update · Issue #1029 · stm32duino/Arduino_Core_STM32 · GitHub](https://user-images.githubusercontent.com/194491/78649661-09196500-78be-11ea-82e5-f4cb91048fa6.png)