GxEPD2 VS nodemcu-devkit-v1.0

And the HelloWorld examples from GxEDP (https://github.com/ZinggJM/GxEPD) as well as GxEDP2 (https://github.com/ZinggJM/GxEPD2)

From what i understand, by uncommenting display class and display driver class in the GxEPD2_display_selection_new_style.h file, the display class object is constructed in line 144 for esp32, as that file is included in the GxEPD2_Example.ino file.

I'd recommend checking out this library GxEPD2 to drive the display contents.

I have been able to run the GxEPD2 example code on my arduino uno which then shows the examples on the screen so I know the screen and connections are working.

This appears to be a NodeMCU, which is an open source dev board: you can just look up the schematics

ESP8266 boards out there, such as the NodeMCU (see here, under ESP-12 Core), normally have a 100uF SMD Tantalum capacitor for this purpose.

It should be fine. The Vin pin is indeed normally Voltage IN but on the nodemcu board as per the schematics it should work given that the 5V supply is powerful enough. I've done it myself multiple times. What type of relay module do you have? Have you connected the grounds together if using separate power supplies?

Board: NodeMcu 1.0 (I de-soldered the LEDs and serial chip to save power once programmed)

The NodeMCU v1.0 is based on the CP2102. Doesn't get much eachier than that.

Guess my only solution would be having to wire it to the USB input somehow. If I could somehow find the VU pin it would allow me to perhaps solder that pin directly to the Vin pin? Unfortunately this version did not populate VU on the board. From what I can see in schematics,(This is V1 so it may not be true) VU has a Schottky Barrier Plastic Rectifier Diode (Schematic) between it and Vdd (VIn) Perhaps tapping into that port could work? (This is V1 so it may not be true) VU has a Schottky Barrier Plastic Rectifier Diode (Diagram) between it and Vdd (VIn)

I don't see VIN max mentioned there but https://github.com/nodemcu/nodemcu-devkit-v1.0/blob/master/Documents/NCP1117ST33T3G.PDF says 10V if yours has the 1117. Either way 12V is pushing it, and as I mentioned lead is greater than 12V when charged, just like other chemistries like Lithiums say ~3.7V but charged are actually around 4.2V

It has the same pinout as a NodeMCU except for that ADC pin where the NodeMCU has a reserved pin. The ADC pin might differ from the A0 pin by including a voltage divider to match a D1 mini, but I'm just speculating and I'd recommend not using it. It looks different because they put the parts of the ESP-12 module directly on the PCB, which is going to same some money on the build. You should be fine treating it like a NodeMCU.

Yes. If you look at the schematic and prints (that's 1.0, but not much has changed), that's R10. Connects GPIO16 (aka XPD_DCDC) to /RST (aka EXT_RSTB). From the ESP8266 datasheet: