display serial interface (DSI)
Display Serial Interface(DSI) is a high-speed serial interface between a display, such as an active matrix, and the controlling processor of a mobile device. The specifications were developed by the Display Working Group and specified by the MIPI Alliance.
The standardization achieves compatibility of the most diverse display modules, which can be further developed in a targeted manner. The DSI specifications take the pixel format into account via the Display Pixel Interface( DPI) and control the display functions via the command set, the Display Command Set( DCS).
Pixels and commands are transferred from the processor to the display via the DSI interface, and status and pixel information is read from the display. In the DSI interface, pixel, status and event data are transmitted as differential signals serially over four lines, whereas in conventional interfaces, data and control information are transmitted to and from the display over a 25- line parallel data bus. The few lines of the serial DSI interface are advantageous for mobile devices because fewer pins are required, and the differential signal transmissionprevents interference from electromagnetic noise because the radiations compensate for each other.
The DSI interface is a high-speed interface with a point-to-point connection via a serial bus with one lane for a high- frequency clock signal and one or more lanes for the data. Each lane consists of two twisted wires. The physical layer is formed by D- PHY, both for the Display Serial Interface (DSI) and the Camera Serial Interface( CSI). In addition to D-PHY, which operates with a synchronous clock at a frequency of hundreds of megahertz up to over 1 GHz, the MIPI Alliance also specifies M-PHY. A low- power serial transmission with integrated clock signal.