= Attaching a 16x2 LCD via I2C This example code shows how to interface the Raspberry Pi Pico to one of the very common 16x2 LCD character displays. The display will need a 3.3V I2C adapter board as this example uses I2C for communications. [NOTE] ====== These LCD displays can also be driven directly using GPIO without the use of an adapter board. That is beyond the scope of this example. ====== == Wiring information Wiring up the device requires 4 jumpers, to connect VCC (3.3v), GND, SDA and SCL. The example here uses I2C port 0, which is assigned to GPIO 4 (SDA) and 5 (SCL) in software. Power is supplied from the 3.3V pin. WARNING: Many displays of this type are 5v. If you wish to use a 5v display you will need to use level shifters on the SDA and SCL lines to convert from the 3.3V used by the RP2040. Whilst a 5v display will just about work at 3.3v, the display will be dim. [[lcd_1602_i2c_wiring]] [pdfwidth=75%] .Wiring Diagram for LCD1602A LCD with I2C bridge. image::lcd_1602_i2c_bb.png[] == List of Files CMakeLists.txt:: CMake file to incorporate the example in to the examples build tree. lcd_1602_i2c.c:: The example code. == Bill of Materials .A list of materials required for the example [[lcd_1602_i2c-bom-table]] [cols=3] |=== | *Item* | *Quantity* | Details | Breadboard | 1 | generic part | Raspberry Pi Pico | 1 | http://raspberrypi.org/ | 1602A based LCD panel 3.3v | 1 | generic part | 1602A to I2C bridge device 3.3v | 1 | generic part | M/M Jumper wires | 4 | generic part |===