TFT Display 1.28 Inch Round TFT LCD Display (GC9A01)

1.28 inch TFT Display Modules a 240RGBX240 dot-matrix TFT LCD module. This module is composed of a TFT LCD Panel, driver ICs, FPC and a Backlight unit

The round modules were originally designed for smart watches and similar applications and provide an interesting change-up from the typical rectangular LCD or OLED modules and work great for making small round gauges of various types or running the Uncanny Eyes application since the round LCDs already look a bit like eyes.

The module can be powered from 3.3V or 5V as it contains a 3.3V regulator, but it is 3.3V logic compatible only. If using with a 5V MCU, be sure to include logic level shifters on the data lines to prevent possible damage.

SPI Interface

This display incorporates the SPI interface which provides for fast display updates.

Since it is a write only device, it does not need the SPI MISO line hooked up.  The  module does bring the CS pin out to the interface which allows multiple devices to share the same SPI bus.

Interface :

• • RES –  Reset for the GC9A01 LCD controller.  Normally HIGH, pull LOW to reset.  This display requires a reset to operate correctly.
  • CS –    Chip Select.  Active LOW
  • DC –   Data / Command.  Determines type type of data being sent to the display.  LOW = Command, HIGH = Data
  • SDA – Connect to SPI MOSI (Data)
  • SCL –  Connects to SPI SCL (Clock)
  • GND – Connect to system ground.  This ground needs to be in common with the MCU.
  • VCC –  Connect to 3.3V or 5V.  This can come from the MCU or separate power supply.