According to the page above, for this display, I have to take the R19 3R path. RESE line. Besides, BS should go to a GND. I soldered everything, but can not make it work. The library is GxEPD2.
Here, you will see "strange pin connection". The library however does have an example with this connection. As I have a regular 1.54 200x200 display I tried with these connections and it works. So ESP32 CAN work connected with these pins. When I connect my 2.7" display to ESP32 through module of the 1.54" display, it works too. So both displays are ok, connections are ok. My schematic is the same as on this module, and on the ESP32 driver board. But, my PCB is not ok.
Can anyone help me troubleshoot this strange problem. I checked 0.5 pins on the FPC connector with a microscope, and it seems ok. I soldered two boards, but no progress. All components are soldered well. To an ESP32 dev board, I connected this PCB with wires.
If I look at the schematic you linked to indirectly (https://www.waveshare.com/w/upload/8/80/E-Paper_ESP32_Driver_Board_Schematic.pdf), it seems that they connect RESE' (not RESE !!!) to VDDUSB (which will be around 5V), possibly through 3R (although it's not clear how the 3R comment in their schematic ties into the actual circuit!). You tie RESE through 3R to GND. So that's a major difference to begin with. The other dip switch position is also implemented differently in your schematic vs. theirs. For some reason you went with 10k for R21 instead of 1Meg in the example schematic; this probably shouldn't make much of a difference, but I don't know what kind of impedance GDR will accept without influencing the internal functioning of the display controller.
In the example schematic, it does indeed, through a 0R resistor. This might be to easily allow for a variation of the board to be manufactured with BS floating or connected to EPD_3.3V, or it may be a simple matter of better PCB routing this way.
Then of course there is the matter of a large part of the example schematic missing from your own, making it unclear how you have implemented the several supply voltages, but notably also the reset circuit for the ESP32 (the part around VT1 & VT2 in the example schematic). Note that a bare ESP32 will not program from within the Arduino IDO without this reset circuit.
There are several key differences between your schematic and the example you linked to, but neither is very clearly documented, so troubleshooting this will requiring having the relevant datasheets at hand, most importantly those of the ePaper display controller and the ESP32S, and systematically going through each net in the schematic to see if it does what the peripherals need to function correctly. With the information you have provided it's a bit of a wild goose chase.
Sorry about the remarks about the RESE/RESE' circuit etc; I misread the Espressif circuit. What they do is connect RESE either through 2R2 + 0R47 to GND (SW1 pins 1 & 2 open), or directly through 0R47 (SW1 pins 1 & 2 closed). Your schematic effectively does something similar so you'd expect that part to function similarly.
Can you show your PCB layout and photos of the finished board?
