Indicators and displays

One of the easiest methods for being convinced that the microcontroller is functioning is adding a code to the program which blinks a LED or LEDs during certain activities. Quite often it is not enough, because it is necessary to forward more information than it is possible by using LED and some applications require user interface where text or numbers are displayed. Here become handy all sorts of indicators and displays, which allow to display numbers, texts or even pictures. One of the most known information displaying devices is computer monitor and typical programmer does not see anything special about using it, but it takes a great deal of effort using microcontrollers to bring every single pixel on the display.

The following chapters are introducing simpler types of displays and screens – indicator with LED segments and two types of monochromatic LCD. In addition to those also LED matrixes and (quite common today) organic color LED (OLED) screens are being used with microcontrollers quite actively. Once filament numerical indicators were used, which had separate glowing filament for each number. There are also electromechanical screens, where different colored facet segments are turned physically. Lately, electronic paper has become popular,which can imitate printings already. First e-papers (electronic paper) were consisting of balls with different colored sides which were turned in electric field. Newer e-papers contain small capsules, where two colors of charged particles are influenced by electric field whether to sing down or stay on the surface. Last two examples are made to visualize different possibilities, but these are not viewed more closely in HomeLab concept.