Review on 🔵 JANSANE 16x2 1602 LCD Display Screen Blue + IIC I2C Module Interface Adapter for Raspberry pi 2 Pack: Enhanced Visuals & Easy Integration by Farhad Cantu

No documentation but it's a 1602 with a PCF8574 chip in a backpack. This is indeed a common setup and there are many libraries for it. In addition to the power supply, only 2 wires are required to set up I2C. My address was 27 and there was yellow tape on the USB port. If your screen is blank or not working but the LED is on, make sure you adjust the contrast (both have been fully adjusted). This is done by adjusting the potentiometer which is the blue box on the back of the LCD with a screw in it. Using a screwdriver, slowly turn the screw until you see individual numbers/letters.