Hi all!
I'm relatively new to the hardware side of things. I have a WiFi LoRa 32 Expansion Kit (found here: WiFi LoRa 32 Expansion Kit – Heltec Automation) with the optional TFT touch screen installed. I'm trying to figure out the display pins to start writing graphics code. I think the actual display used is an ST7789, but I can't swear to it.
But I have no idea which pins are used. Opening the case, there's noting obvious and I don't feel great tearing it down further.
I'm wondering if anybody has a similar setup and can give me info on the pinout, or outline a methodology to figure out which pins are used.
Lots of folks ask similar questions; there is at least one other active thread going. Unfortunately, the only advice I have is contact Heltec and pray.
I don't have that one but I used to have a Heltec OLED board. The best resource is their sample code that ships with the library.
I don't know the answer to your question but if I had your problem I'd be looking at whether the display was I2C or SPI then using an appropriate library to drive the display through one of those interfaces. No need to worry about which pins are being used, at least at the start of experimenting.
Thanks for the replies guys! I appreciate it. Looks like the Heltec examples in their GitHub repository finally caught up with the hardware, and there is a V4 touchscreen example with all the info.
Thanks!!!
Heltec has their own version of the Espressif ESP32 board
package. Plus a library named "Heltec Extended Example Library".
Some of examples include pin numbers for various hardware. I have
not tried this yet because I am waiting for my Heltec V4.
Hello Mr! 
Did you manage to connect the display to the v4 module?
The TFT uses SPI, the Touch uses I2C protocol. If you could help me, how did you solve it, I would appreciate it.
I only have the SPI part working, that's ok, but I2C is not compatible with the touch part of my display. What display are you using?