Method and device for switching detection of display screen parameters using hdmi interface of PC host

Abstract

A method for switching and detecting parameters of a display screen using an HDMI interface of a PC. A switching device is set to switch the display screen and detect the connection between the host computer and the MCU inside the bus switching device. When the display screen is replaced, the MCU receives the host computer to modify the After the requirements of the screen parameters, connect HDMI_HP to GND, the host thinks that the screen is disconnected, and turn off the video signal output; the MCU outputs the control signal, so that the I2C bus is disconnected from the host, and then the EEPROM and the MCU are connected through the I2C bus; The MCU parses the new EDID information sent by the host, and writes it into the EEPROM through the I2C bus; the MCU reconnects the EEPROM to the host's I2C; reconnects HDMI_HP to HDMI_5V0, the host thinks that a new screen is connected to the HDMI interface on; read the new EDID information, and output the video signal to the new display screen according to the new video parameters. It achieves the purpose of outputting RGB signals of various parameters through the HDMI interface, and can be used to detect TFT‑LCDs with different resolutions and different timing parameters.

Description

technical field [0001] The invention relates to the technical field of liquid crystal displays, in particular to a method and a device for detecting the switching of display screen parameters by using an HDMI interface of a PC host. Background technique [0002] This article involves a method of display screen detection. In the past, RGB interface screens needed to use FPGA or mid-to-high-end SOC to generate video signals, and then play various test pictures for detection. [0003] This article uses the HDMI interface of the general PC to convert the RGB signal. However, as a testing device, it is necessary to replace the screen parameters. For a conventional HDMI screen, the host connects to the screen through the HDMI port, and the host reads the resolution of the screen from the HDMI interface. and timing information (called EDID), and finally send out the appropriate video signal to drive the screen, the EDID information of the screen is burned in in the factory, and gen...

AI Technical Summary

Problems solved by technology

[0003] This article uses the HDMI interface of a general PC to convert the RGB signal. However, as a detection device, it is necessary to change the screen parameters. For a conventional HDMI screen, the host is connected to the screen through the HDMI port, and the host reads the resolution of the screen from the HDMI interface. and timing information (called EDID), and finally send out an appropriate video signal to drive the screen. The EDID information of the screen is burned in the factory and generally does not allow users to modify it.

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