ESP8266 Community Forum

I have a wemos d1 mini that I am trying to cummunicate with using the serial monitor. this usually works if I have an simple sketch that just prints some stuff to the monitor but if I do anything more complected the d1 mini just keeps disconnecting and connecting and everytime I have to wait for the serial port to appear and then start the serial monitor to see a couple of lines appear and then it disconnects again. sometimes it works for a while and sometimes it doesn't even work for a few seconds. I have tried using different usb ports and different cables and I am running ubuntu mate 16.04 on the computer that I have it connected to.

It sounds like a power supply issue.
You might want to try with a WeMos power shield or a powered USB-hub.

Alternatively, as a quick fix, set the RF power level of your WeMos to a minimum.

QuickFix wrote:It sounds like a power supply issue.
You might want to try with a WeMos power shield or a powered USB-hub.

Alternatively, as a quick fix, set the RF power level of your WeMos to a minimum.

I already tried the powered usb hub inside my monitor

I have exact same problem on my d1 boards. I foundout that VCC pin (16 of CH340 ) is connected to 3.3v instead of 5v from USB. The solution is: rise 16 pin of CH340 and connect it ot 5v. Now connection is stable.