3Pcs 1.28 Inch TFT LCD Display Module Round GC9A01 Driver IPS LCD Screen Module Circular 4 Wire SPI Interface for Arduino

I previously was using a different version of these display modules but the extra Z height from the soldered header on the PCB cutout was annoying for integration. I bought this set instead since it cleanly routes the connection to the back of the display, and also comes with the bonus of having threaded posts already applied for mounting. I've confirmed the display works with both the Adafruit GFX and LovyanGFX libraries using an ESP8266 dev board. There are a few things that would improve these modules. First, I think it would be nice for the provided cables to use male dupont connections instead of female, so they can be connected to a breadboard. For integration, I'm going to crimp on my own connector anyways, so it would be nice if the out-of-the-box connection was more useful during the prototyping stage. Second, the mounting posts do not have end stops. If you use a screw that is too long, you can accidentally screw through the PCB and push out the display and damage it. I accidentally did this but caught it and stopped myself before destroying the display. Ideally the threaded posts should be closed at the end. One smaller nitpick, the provided documentation (linked under "Product description" in case you initially missed it like I did) does not show the distance between the threaded posts. There is enough information to calculate it from what's given and you can verify with a caliper, but it would be nice to have that information provided as that is the most important measurement for mounting this display centrally on some object. English documentation would also be a plus but not a huge deal. If you are having troubles, make sure your connections between the display and your microcontroller are not too long, that you are correctly toggling Chip Select, and that your SPI interface is configured correctly with your library. In particular I tried inserting wire extensions into the provided cable to connect it to a breadboard, but this caused the connection length to be too long (or maybe the contact was flakey and it would have worked fine with a proper wire) and the display wouldn't process commands until I connected it directly to the microcontroller without any extensions.

This is a great little display, decently priced, pairs well with tiny microcontrollers like the Seeed XIAO ESP32-C3 (which is what I used to test the ones I received). All three displays that I received worked. Other reviewers have mentioned needing to change the SPI mode or frequency, but the default values worked fine for me. However, since the Seeed XIAO ESP32-C3 uses different SPI pins than the library's defaults (D10 and D8 instead of D11 and D13 for COPI/MOSI and SCK, respectively), all I needed to do to make the GC9A01A Arduino library's "graphicstest" example work with it was to use the full display constructor so I could pass in the correct SPI pin numbers: #define TFT_SCLK 8 // D8/GPIO8 to display SCL (pin 3, white: SPI clock signal input) #define TFT_COPI 10 // D10/GPIO10 to display SDA (pin 4, yellow: SPI data input) #define TFT_RST 5 // D3/GPIO5 to display RES (pin 5, orange: display reset) #define TFT_DC 4 // D2/GPIO4 to display DC (pin 6, green: data/command select) #define TFT_CS 3 // D1/GPIO3 to display CS (pin 7, blue: chip select) #define TFT_BL 2 // D0/GPIO2 to display BLK (pin 8, purple: backlight control) Adafruit_GC9A01A tft(TFT_CS, TFT_DC, TFT_COPI, TFT_SCLK, TFT_RST, -1); Check your microcontroller's pinout for the locations of the COPI/MOSI and SCK pins; the other four can be changed to whatever open GPIO pins you prefer. (I chose GPIO2-5 to leave the UART and IIC pins open, at the expense of any analog I/O.) As long as you're using the correct pins, it's very easy to get up and running.

None of the three are working so far with my existing demo for the GC9A01 controller. I have the TFT_eSPI Smooth_Graphics/AntiAliasedClock demo running on 1.28” displays, of the type that have pins on them and which use the same controller, connected to an esp32s2-mini processor. I added code to light the built-in led during NTP request processing. That code executes without error on the Jessine displays but nothing is displayed - the blue led flashes as NTP requests are processed and things appear to be proceeding as expected but nothing is displayed. The backlight does come on. I have experimented with the SPI_FREQ and even added a reset signal but no joy. The other displays continued to work with these test changes tho slowly as expected. I have verified that both the power and signaling are 3.3v. None of these will display anything.

These are really pretty displays. Well built, high quality and i love the standoffs on the bottom. These are not those flimsly cheap things. As others have pointed out, it's all about the frequency. If you are getting white stripes, or gray display or other non display issues, you have to change your frequency. For example, the default frequency in my Adafruit_GC9A01A.cpp library file for the esp32 (or ESP8266) was 40mhz (40000000). That was not working at all on my project (was using an esp32 DevKit V1). I had to set it to 32mhz (32000000) and it started working. These are in fact great displays. But they wont necessarily work right OOTB. Just adjust the FREQ and your good to go! Highly recommend. as mentioned very good quality Not cheaply built.

The mounting screw holes are exactly what I needed for my project!