I’ve talked about HD44780 displays before – they’ve been a mainstay of microcontroller projects for literal decades. In the modern hobbyist world, there’s an elephant in the room – the sheer variety of I2C and SPI displays you can buy. They’re all so different, some are LCD and some are OLED, some have a touchscreen layer and some don’t, some come on breakouts and some are a bare panel. No matter which one you pick, there are things you deserve to know.
These displays are exceptionally microcontroller-friendly, they require hardly any GPIOs, or none extra if you already use I2C. They’re also unbelievably cheap, and so tiny that you can comfortably add one even if you’re hurting for space. Sure, they require more RAM and a more sophisticated software library than HD44780, but with modern microcontrollers, this is no problem at all. As a result, you will see them in almost every project under the sun.
What do you need for those? What are the requirements to operate one? What kind of tricks can you use with them? Let’s go through the main aspects.
