Control system for a 8×8 bi-color dot matrix display

Due to the advantages it presents, we are today witness to an unprecedented expansion of applications of LED optoelectronic devices. In addition to the development of lighting systems, display systems record an upward trend. The latter, in addition to requirements related to ensuring a good visibility, very often require dynamic change of the color or displayed message. Many display panels have as basic component the 8×8 LED matrix. Because these matrix can be fabricated encompassing LEDs of several colors, it becomes essential to ensure voltage control systems in order to ensure their use at maximum possibilities. This paper proposes an assembly that works based on a single IC - MAX7219 to control a 8×8 matrix with two colors. Are presented the electronic assembly and a number of issues related to the practical implementation and programming of the microcontroller. The application can be extended to a large number of 8×8 matrices. Obtain such a special visual effect by changing the color of text displayed dynamically.