This display now comes with an EYESPI connector. This connector allows you to connect your display without soldering. There are EYESPI cables available in multiple lengths, which means you can find one to fit any project. This is especially useful if your project requires the display to be freestanding, and not tied directly into a breadboard. Inspired by the popularity of STEMMA QT, it provides plug-n-play for displays!
The EYESPI connector is an 18 pin 0.5mm pitch FPC connector with a flip-top tab for locking in the associated flex cable. It is designed to allow you to connect a display, without needing to solder headers or wires to the display.
The EYESPI connector location on this display is indicated below.
The EYESPI cables are 18 pin 0.5mm pitch flex cables. They are ~9.6mm wide, and designed to fit perfectly into the EYESPI connector. Adafruit currently offers EYESPI cables in three different lengths: 50mm, 100mm, and 200mm.
Wiring your EYESPI display to a microcontroller via the EYESPI connector requires the EYESPI breakout board and an EYESPI cable.
The following example shows how to connect the 2.8" TFT touchscreen to a Feather RP2040 using the EYESPI breakout board.
Connect the following Feather pins to the associated EYESPI breakout pins:
- breakout Vin to Feather 3.3V (red wire)
- breakout Lite to Feather 3.3V (yellow wire)
breakout Gnd to Feather GND (black wire)
- breakout SCK to Feather SCK (grey wire)
breakout MISO to Feather MI (green wire)
breakout MOSI to Feather MO (purple wire)
- breakout SDA to Feather SDA (blue wire)
- breakout SCL to Feather SCL (yellow wire)
- breakout TCS to Feather D5 (blue wire)
- breakout DC to Feather D6 (orange wire)
- breakout RST to Feather D9 (cyan wire)
- breakout SDCS to Feather D10 (pink wire)
Finally, connect your display EYESPI connector to the breakout EYESPI connector using an EYESPI cable. For details on using the EYESPI connector properly, visit Plugging in an EYESPI Cable.
Though there are 18 pins available on the EYESPI connector, many displays do not use all available pins. This display requires the following pins:
- Vin - This is the power pin. To power the board (and thus your display), connect to the same power as the logic level of your microcontroller, e.g. for a 3V micro like a Feather, use 3V, and for a 5V micro like an Arduino, use 5V.
- Lite - This is the PWM input for the backlight control. It is by default pulled high (backlight on), however, you can PWM at any frequency or pull down to turn the backlight off.
- Gnd - This is common ground for power and logic.
- MISO - This is the SPI MISO (Microcontroller In / Serial Out) pin. It's used for the SD card. It isn't used for the display because it's write-only. It is 3.3V logic out (but can be read by 5V logic).
- MOSI - This is the SPI MOSI (Microcontroller Out / Serial In) pin. It is used to send data from the microcontroller to the SD card and/or display.
- SCK - This is the SPI clock input pin.
- TCS - This is the TFT SPI chip select pin.
- RST - This is the display reset pin. Connecting to ground resets the display! It's best to have this pin controlled by the library so the display is reset cleanly, but you can also connect it to the microcontroller's Reset pin, which works for most cases. Often, there is an automatic-reset chip on the display which will reset it on power-up, making this connection unnecessary in that case.
- DC - This is the display SPI data/command selector pin.
- SDA - This is the I2C serial data pin. Connect to the desired I2C data pin on your microcontroller.
- SCL - This is the I2C serial clock pin. Connect to the desired I2C clock pin on your microcontroller.
- SDCS - This is the SD card chip select pin. This pin is required for communicating with the SD card holder onboard the connected display.