HD44780 LCD Display: Principles, Compatibility, and Character Usage

The majority of LCD displays currently produced use the HD44780 chip, and their display principles are the same. This means that a display control program can be used for various LCD displays without the need to rewrite the program for each type, making it highly compatible. The LCD module has a storage module that stores a large number of character graphics to be used for display, with approximately 160 characters including basic symbols such as letters, numbers, punctuation, and Japanese characters. Each character has a fixed identifier, so when a character needs to be displayed, the corresponding identifier can be called. Additionally, programming can be done through assigning values, such as defining a character constant Y and assigning a character from the LCD storage to Y, making it easy to use custom constants. The corresponding pins are listed in a table.