Connect the Teensy 3.1 to the LCD as per the table below (if your LCD doesn’t have the exact pins as shown below you will need to modify them to suit).
|Nokia 5110 LCD||Teensy 3.1|
You will need to install the following Adafruit libraries.
Reopen the Arduino software and open the “pcdtest” example for Adafruit-PCD8544-Nokia-5110-LCD-library,
Un-comment the following line.
Adafruit_PCD8544 display = Adafruit_PCD8544(5, 4, 3);
Compile and upload the example and you should see the following on the LCD