Mayata WEMOS D1 Mini Pro 4MB/16MB External Antenna Connector NodeMCU Based esp8266 Series Antenna ESP-8266EX CP2104 Development Board (Development Board + Antenna 32MBIT=4MB)

When flashing the module, it always went into a boot loop (exception in ets cause 2). I tried altering the clck speed, the communications rate, and many other parameters without success (and I have substantial experience). I also tried it with Tasmota as well as new code via the Arduino IDE. Seems like I have a defective module. That can happen, but I am not the only one.

If you are going to use the external antenna instead of the onboard ceramic antenna, you need to remove the zero-ohm resistor next to the antenna connector, and solder bridge as shown by the red arrow. Otherwise, the external antenna isn't connected. Once done, everything works great.

ENOUGH SAID!

Wanted to simply load code from a D1 mini from a previous project, but wasted time on this. It loaded code, but would not run. This code is running on other D1 mini modules. Chip got hot. Appears to be bad hardware. Returning.Side note. This device does not have a diode to avoid 5V back feeding to the USB. This is populated with a 0R resistor. Probably not important in most applications, but the pictures do not match what you get.As others noted, the 0R for the antenna selection is setup for using the ceramic. The module does not have FCC approval and is not meant for commercial use.

I had ordered 3 d1mini pros from another company, they wouldn't communicate with my computer, but they were also on 20 for 3. Ordered this one, it shipped fast, plugged it in, flashed it, and it works fine. As others have said you have to move the antenna resistor, but that's not hard. I kinda think they should ship with the resistor solder to the external antenna, cause if you didn't want to use the external why not just order a regular d1mini. But overall I'm happy.