ESP8266 Community Forum

- Mon Mar 19, 2018 11:30 pm #74728 According to the specs, the CP2104 USB chip on a Wemos D1 Mini drains 18mA when active and only 200μa when disabled.
Is it possible to disable that chip by software?

- Tue Mar 20, 2018 6:27 am #74734 maybe from the USB side but surely not from the serial side (the one exposed to the esp).

generally on all "integrated" boards:
This would not be problematic if it were implemented as "bus powered" but most boards are idiotically implemented as selfpowered; who needs the part powered when not connected to usb???

- Tue Mar 20, 2018 8:00 am #74739

maybe from the USB side but surely not from the serial side (the one exposed to the esp).

generally on all "integrated" boards:
This would not be problematic if it were implemented as "bus powered" but most boards are idiotically implemented as selfpowered; who needs the part powered when not connected to usb???

How do one do that: implement as "bus powered" vs. "implement as selfpowered"?

If they are implemented as selfpowered, isn't it useful to use
Serial.stop();
?
and set the TX GPIO to "0";

- Tue Mar 20, 2018 9:09 am #74742 I don't know if they have some intelligence to detect "no traffic" to enter some standby mode, I doubt it. In the silab datasheets (current and old parts) I only find information to supply current - normal vs suspended and by "suspended" referring to the USB bus.