Vbus Detection

dimax · ‎2013-02-28

Posted on February 28, 2013 at 16:47

Hi,

I'm developing a self powered USB FS Peripheral Only Device. To detect a USB cable connection to Host I assume to use

SRQINT bit in OTG_FS_GINTST register.

But for some reason I can not initially clear this bit. I wrote a ''1'' init it to no avail.

The VBUS level is about 0.8V measured on PA9 (STM32F20xx).

I played with GCCFG_VBUSBSEN and GCCFG_VBUSASEN it also did not help.

What's wrong?

dimax · ‎2013-02-28

Posted on March 01, 2013 at 08:03

Alternatively can someone suggest what is the right way to detect USB cable insertion in self powered USB FS peripheral device?

I still can not see any way to clear SRQINT after power reset before USB cable is connected.