Most of you’ve heard of the HD44780 before, but do you really know what is the behind story for this buddy?

Today, you will learn and gain knowledge, from the very beginning part of the HD4780-based displays to its software part.

Ok, let’s get the learning party started…

The HD44780 LCDs with AVR Microcontroller

You can simply apply the HD44780-based LCDs displays to be operated, either in 4-bit or 8-bit mode. If you selecting the 4-bit mode, the two nibbles of each bytes is sent in a sequence on the high 4 bits of the data bus, such as in this order: DB7…DB4 and the low bits, DB3-DB0 are not connected.

Beside that, there are also the RS (Register Select) lines, which use to determine if the information should be interpreted as data or a command. The R/W (Read/Write) line plays its important role to switch the data direction between the module and the microcontroller. Read more »