ESP8266 Community Forum

Posted: **Wed Aug 10, 2016 1:53 am**

With USB, to get the host's attention as a low-speed device, a pull-up resistor must be between D- and VCC... but I'm not sure if the pullups on the ESP are reliable enough to be that pull-up. If that is possible, we could have USB on the ESP with 0 external components. I've just read so much about various properties of the pullup resistors. Does anyone know if they would be suitable?

Posted: **Wed Aug 10, 2016 8:08 am**

Internal pullups are about 100K, and if I remember the USB protocol looks for a 1K5.

Posted: **Wed Aug 10, 2016 10:17 am**

From my experience probably not, very weak pullups, very!

RichardS

ESP8266 Community Forum

Are the pull-ups on the ESP suitable to indicate on-bus?

Are the pull-ups on the ESP suitable to indicate on-bus?

Re: Are the pull-ups on the ESP suitable to indicate on-bus?

Re: Are the pull-ups on the ESP suitable to indicate on-bus?