Getting into STM32F777 DFU mode

[TallGUY]

Posted on May 27, 2017 at 04:09

Is there anything I am missing while trying to get my STM32F777 chip into DFU mode?

I have a 25 MHZ OSC (HSE), NRST is pulled high with a 10K resister and BOOT0(pin138) is pulled low with a switch to pull it high on reset/power on. 

The chip is totally blank never been programmed, do I need to set any of the option bits or are the defaults correct? 

How does the chip detect that USB has been connected; the VBUS pin, the ID pin, or just USB communication?

I would appreciate any help, thanks,

Sheldon 

[TallGUY · Accepted solution]

Posted on June 06, 2017 at 05:02

So it was a USB impedance problem. thanks for the help