Rows and cols are the rows and columns on the display (e.g. This is the main initialisation function and must be called before you use any other LCD functions. Int d0, int d1, int d2, int d3, int d4, int d5, int d6, int d7)

int lcdInit (int rows, int cols, int bits, int rs, int strb,.

The LCD library will call pinMode functions as required. To use the LCD library, you’ll need this at the start of your program: #include įirst, you need to initialise wiringPi in the way you want to. If not, the display can potentially present 5v back to the Pi which is potentially damaging. When using a 5v display, make sure you always connect the R/ W pin on the display to ground to force the display to be read-only to the host. At best you’ll destroy the pin drivers, at worst you’ll destroy your Pi.

The LCD display can be either a 5V display or a 3,3v display, however if we are using a 5V display then we must make absolutely sure the display can never write data back to the Raspberry Pi, otherwise it will present 5V on the Pi’s GPIO pins which will not be good. If you move to using a 4-bit interface (trivial in the code), then it’s 4 more displays – 12 LCDs! However I suspect the rest of the wiring might be somewhat challenging… Wiring is described at the end of the this page. In 8-bit mode, the first display needs 10 GPIO pins and each additional display needs just one more pin, so with a maximum of 17 GPIO pins, that’s 8 displays. It is possible to wire up more than one display. The library is simple to use in your own programs, however wiring the displays up may be challenging, so do take care. The following Fritzing diagrams describe how to connect the displays directly to the on-board GPIO of a Raspberry Pi in both 8 and 4-bit modes: See this page for more details of the Adafruit display setup using wiringPi Top: standard 16×2 LCD display connected directly to a Raspberry Pi and (below) an Adafruit RGB back-lit LCD plate with control buttons.

The displays can be connected directly to the Pi’s on-board GPIO or via the many GPIO expander chips supported by wiringPi – e.g. It allows you to connect multiple displays to a single Raspberry Pi. The wiringPi LCD devLib allows you to drive most of the popular 1, 2 and 4-line LCD displays that are based on the Hitachi HD44780U or compatible controllers.

Raspberry pi i2c fritzing