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This project provides a universal interface to drive the popular Hitachi HD44780 LCD controller.

YALI (Yet Another LCD Interface) is an open-source project to provide a universal interface to drive the popular Hitachi HD44780 LCD controller. This module supports 3.3V and 5V MCUs and hardware development platforms, including Arduino, STM32, PIC, and ESP8266.

The hardware module of this project consists of a 74HCT08 CMOS AND gate and a 74HC595 8-bit serial-in, parallel-out shift register. This module uses the MP1540 step-up converter to power the LCD unit connected to the system. The module has the jumper to select 3.3V or 5V DC power input.

The YALI library is developed using C and is designed to be easily integrated with any C/C++ embedded toolchain. At the initial design stages, this library was successfully tested with all Arduino development boards, NodeMCU, STM32 Blue Pill, etc. The target system must have three digital output lines with 5V or 3.3V logic levels to interface with the YALI module. As mentioned earlier, this module works successfully with 5V or 3.3V power sources and logic levels.

The YALI library provides a unified API to control the HD44780 LCD controller. It has functions to handle cursor control, custom character loading, LCD backlight control, etc.”

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