• 1.3″ TFT LCD with wide ±80° viewing angle
• RGB Full color display
• 240 x 240 high resolution 260PPI display
• SPI interface w/out CS pin
• ST7789 LCD display controller
• 3.3 operation
• Operates at 3.3V, so if using with a 5V MCU, include logic level shifters on the data lines to prevent damage.  The module doesn't have a 3.3V regulator so you must power with 3.3V.
  
  This is a write only device and doesn’t need the SPI MISO line hooked up.  The  module also doesn’t bring the CS pin out to the interface which helps to lower the pin count.  Unfortunately, it can’t be used with other SPI devices on the same bus simultaneously. 
• Connecting the display via a 7 pin header.

1 x 7 Header

• GND – Connect to system ground.  This ground needs to be in common with the MCU.
• VCC –  Connect to 3.3V.  This can come from the MCU or  separate power supply.
• SCK –  Connects to SPI SCK
• SDA – Connect to SPI MOSI (Data)
• RES – Reset for the ST7789 LCD controller.  Normally HIGH, pull LOW to reset
• DC –   Data / Command.  Determines type type of data being sent to the display.  LOW = Command, HIGH = Data
• BLK – Backlight Control.  If left unconnected, the backlight is always on.  Pull LOW to turn off