Among many liquid crystal displays, TFT-LCD signal interfaces include SPI, MCU, RGB, LVDS, Mipi, EDP, HDMI and other types. Among these interfaces, MCU, RGB, LVDS, Mipi and other signal interfaces are commonly used in the market. Today, we mainly talk about the characteristics and signal composition of RGB interface:
As the name suggests, RGB interface is to realize the data interaction between CPU and LCD based on three primary color data signals. There are many working modes of this interface signal, but without exception, all need to pass through multiple data lines. According to different number of signal lines, the interface can be subdivided into several working modes such as 6bit, 16bit, 18bit and 24bit. The pin definition is usually CS (alias: chip selection pin, usually used to select IC) + Vsync (field synchronization signal, select the effective field signal interval on LCD) + Hsync (line synchronization signal, select the effective line signal interval on LCD) + de (data enable signal) + data line (R0 ~ Rx, G0 ~ GX, B0 ~ BX, x = actual data / 3-1, such as 24bit, x = 24 / 3-1 = 7) + power line (VCC, GND, Leda, ledk, etc.).
There are also advantages and disadvantages of this interface. Because the RGB interface occupies more resources, the LCD refresh speed using this interface is very fast, and the software control is relatively simple. Moreover, because the display data of this interface does not need to be written into the memory for processing, it can be directly written into the LCD for display, so the response speed and refresh speed Compared with MCU interface, it is much faster.