Liquid Crystal Displays (LCDs)

Usually, IoT products come with a mobile or web application to let users interact with the product. However, we may sometimes need to display direct information on the device itself. For such products, we can integrate a display with ESP32.

LCDs are a common type of display that we can use in our IoT projects. They are highly available on the market with a low price tag. They come in a variety of sizes, in other words, columns and rows, that we can select; for example, 16x2, which means there are 16 columns and 2 rows on that type of LCD, with a total of 32 characters to display at a time. There is one such LCD shown in the following figure:

Figure 3.1 – 16x2 LCD

An LCD can operate in 4-bit mode or 8-bit mode, which defines the number of data lines to drive the LCD. However, it is too costly in terms of the GPIO resources on ESP32. Therefore, it is a good idea to use an I2C adapter module to reduce the number of pins...