Eight-port HDMI reinforced KVM switcher

Abstract

The invention belongs to the technical field of human-computer interaction, and particularly discloses an 8-port HDMI reinforced KVM switcher. According to the invention, by cascading the multi-stage high-definition conversion chips, a certain path of the eight paths of HDMI is switched to directly output the HDMI signal, and full-high-definition HDMI (# imgabs0 #) digital signal switching is realized, so that the signal transmission is stable, the loss is small, the signal is balanced, the signal amplitude is adjustable, and the high-definition switching scene is satisfied. In addition to directly outputting HDMI signals, digital video signals can be converted into VGA video signals to be output through the HDMI-to-VGA chip, so that the application flexibility is improved, the cost can be reduced, and the efficiency can be improved. The multi-stage USB HUB chip driver enhances the USB signal, enhances the anti-interference capability of the USB signal, can adapt to operating systems such as WINDOWS, Kylin and Tao, does not need to optimize the host USB driver, and solves the problem that the USB peripheral cannot be identified across platforms. One-out-of-multiple switching of the USB signal is realized by controlling gating of the cascade analog switch, and the reliability of switching of the USB input signal is ensured.

Description

Technical Field

[0001] The present application belongs to the field of human-computer interaction technology, and more specifically, relates to an 8-port HDMI reinforced KVM switch. Background Art

[0002] A rugged KVM switch is a KVM (Keyboard, Video, Mouse) switch designed for use in harsh environments or special application scenarios. Currently, rugged KVM switches have 8-way VGA switches that can realize human-computer interaction. A VGA switch is a device used for switching video signals. It allows users to switch to one or more VGA displays through one or more VGA input sources (such as computers, game consoles, DVD players, etc.). Since analog signals have ghosting and water ripples after switching, high-resolution ( On the other hand, there are incompatibility issues with USB drivers on different hardware architecture platforms and operating system platforms of the host, and USB peripherals cannot be recognized when switching USB input signals across hardware or software platforms. Summary of the invention In view of the defects of the prior art, the purpose of this application is to provide an 8-port HDMI reinforced KVM switch, aiming to solve the problems of poor display effect of the existing reinforced KVM switch at high resolution and inability to recognize USB peripherals across platforms.

[0003] The present application relates to an 8-port HDMI reinforced KVM switch, including: a main controller, four HDMI switch chips, a VGA conversion chip, a USB signal enhancement driver module, two sets of two-channel single-pole four-throw analog switches, a high-speed double-pole double-throw analog switch and a USB HUB expansion chip; wherein, The main controller is used to control the channel gating of the HDMI switch chip through the I2C bus according to the display channel data information to realize multiple-choice-1 switching of the display signal, and control the channel gating of the two-channel single-pole four-throw analog switch through the IO interface to realize multiple-choice-1 switching of the USB signal; The four HDMI switcher chips are in a two-stage cascade structure, the first stage is composed of the first to third HDMI switcher chips, and the second stage is the fourth HDMI switcher chip, realizing 8-way HDMI input signals and 1-way HDMI output signal; the HDMI output signal is directly output to the display, or converted to a VGA signal by a VGA conversion chip and then output to the display; The USB signal enhancement driving module, two groups of two-channel single-pole four-throw analog switches, the high-speed double-pole double-throw analog switch and the USB HUB expansion chip are electrically connected in sequence, wherein the USB signal enhancement driving module enhances the 8-way USB signal and sends it to the two groups of two-channel single-pole four-throw analog switches for four-to-one output, the output signal is sent to the high-speed double-pole double-throw analog switch for two-to-one output, and is sent to the upstream port of the USB HUB expansion chip for USB signal expansion and shaping before outputting to the keyboard and mouse.

[0004] Preferably, the reinforced KVM switch reserves an external I2C interface; The I2C interface supports an external controller to program the HDMI switch chip register to implement the equalizer at the HDMI input end and the signal amplitude adjustment at the output end to meet the display signal adjustment requirements in different application environments.

[0005] Preferably, the USB signal enhancement driving module is composed of 8 USB HUB expansion chips, and each USB HUB expansion chip is responsible for shaping one USB signal.

[0006] Preferably, the main controller obtains the display channel data information in any of the following ways: 1) Real-time detection of key switches, when a key is triggered, obtain the key value through different IO ports; 2) Receive the KVM switching command sent by the external communication interface and parse the command.

[0007] It should be noted that this application provides multiple control methods to adapt to different scenarios.

[0008] Preferably, the main controller adopts GD32F103XX series or other main control chips with I2C, network controller, CAN port, serial port, and has the functions of key detection processing, network control, LED indicator light control, data communication and issuing control instructions.

[0009] Preferably, the HDMI switch chip is MS9601A, and the VGA conversion chip is MS9291.

[0010] Preferably, the main controller realizes the equalization adjustment of the input HDMI signal and the amplitude adjustment of the output HMDI signal by setting the register RX receiving EQ value and the register TX output value of the MS9601A.

[0011] Preferably, the adjustment range of the input data signal amplitude is 150mv-1200mv, and the RX input signal adjustment includes: EQ frequency starting point adjustment, EQ eye height adjustment, high frequency compensation point adjustment and low frequency gain adjustment, which are achieved by configuring corresponding register values.

[0012] Preferably, the output adjustment adjusts the amplitude of the output signal by adjusting the current value of the register, and the larger the current value, the larger the amplitude.

[0013] Preferably, the two-channel single-pole four-throw analog switch is CH444, the high-speed double-pole double-throw analog switch is RS2227XN, and the USB HUB expansion chip is a FE1.1S (SL2.1S) chip.

[0014] In general, the above technical solutions conceived by this application have the following beneficial effects compared with the prior art: (1) This application uses a cascade of multi-level high-definition conversion chips to switch one of the 8 HDMI channels to directly output HDMI signals, full high-definition HDMI ( ) Digital signal switching, stable signal transmission, low loss, balanced signal, adjustable signal amplitude, meet the high-definition switching scenario. In addition to directly outputting HDMI signals, you can also use HDMI to VGA chips to convert digital video signals into VGA video signal output, which increases application flexibility, reduces costs and improves efficiency.

[0015] (2) To improve the reliability of cross-platform USB switching, this application enhances the USB signal through a multi-level USB HUB chip driver, which enhances the anti-interference ability of the USB signal. It can adapt to WINDOWS, Kylin, Taobao and other operating systems without optimizing the host USB driver, solving the problem of cross-platform USB peripherals not being able to be recognized. By controlling the cascade analog switch selection, the USB signal multiple-choice 1 switching is realized, ensuring the reliability of USB input signal switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a block diagram of HDMI display switching of an 8-port HDMI reinforced KVM switch provided in an embodiment of the present application.

[0017] Figure 2 This is a schematic diagram of implementing an HDMI to VGA interface provided in an embodiment of the present application.

[0018] Figure 3 This is a USB switching block diagram of an 8-port HDMI reinforced KVM switch provided in an embodiment of the present application.

[0019] Figure 4 It is a flow chart of the HDMI switching chip signal adjustment method provided in an embodiment of the present application.

[0020] Figure 5 It is a schematic diagram of the hardware module structure of a reinforced KVM provided in an embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0022] The term "and / or" in this article is a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The symbol " / " in this article indicates that the associated objects are in an or relationship, for example, A / B means A or B.

[0023] The terms "first" and "second" in the specification and claims herein are used to distinguish different objects rather than to describe a specific order of the objects. For example, a first response message and a second response message are used to distinguish different response messages rather than to describe a specific order of the response messages.

[0024] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0025] In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more than two. For example, multiple processing units refer to two or more processing units, etc.; multiple elements refer to two or more elements, etc.

[0026] For ease of understanding, the English abbreviations and related technical terms involved in the embodiments of the present application are explained and described below.

[0027] The HDMI interface contains multiple channels, each of which is responsible for different functions. The HDMI interface contains 4 pairs of TMDS differential pairs (1 pair of clock + 3 pairs of data), a pair of I2C, HPD, and CEC. The TDMS bus is used to transmit video and audio information; the I2C channel is used for communication between the source device and the display device to obtain basic information of the display (such as EDID information) and other control data; the CEC bus is used to allow users to control the connection of multiple HDMI devices through a remote control: the HPD channel is used to detect whether the device is connected to the HDMI port and trigger the corresponding initialization process.

[0028] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0029] The main controller receives data and / or collects key input signals through various communication ports (RS232, RS485, CAN, network), parses the data message, obtains the display channel data information, controls the channel selection of the HDMI switcher chip through the I2C bus, realizes multiple-choice switching of display signals, and the output display interface supports both HDMI and VGA signals; the keyboard and mouse are combined into one USB signal, and the IO interface controls the cascaded analog switch selection to realize multiple-choice switching of USB signals.

[0030] The detailed technical solution is as follows: The main controller receives and parses the external communication interface message to realize KVM switching. The KVM switching is specifically as follows: the main controller receives the control command sent by the external communication interface, parses and processes the control message, controls the analog switch channel gating through the IO interface to switch the USB signal; sends a command through the I2C bus to control the HDMI display switching chip action gating. Alternatively, the main controller detects the user's key press in real time, obtains the key value when a key is triggered, and realizes KVM switching.

[0031] Preferably, the domestic HDMI switcher chip can realize 3-input and 1-output switching display of HDMI signals with high resolution, and through two-level cascading, it can realize 8-way HDMI signal input and 1-way HDMI signal output to an external display device.

[0032] Preferably, in order to adapt to the VGA display device interface, the HDMI signal can be converted into a VGA signal through a VGA conversion chip and output to an external display device.

[0033] Preferably, 8 external host input USB signals (host USB mouse and keyboard are combined into 1 USB) are sent to a multi-channel analog two-channel single-pole four-throw analog switch after the signal is adjusted by the driver chip. The four-to-one switching of USB signals is realized by controlling the coding address, and then the two-to-one switching of two USB signals is realized through a high-speed bipolar double-throw analog switch. Finally, USB keyboard and mouse input is realized through the USBHUB expansion chip.

[0034] The main controller controls the input equalization and output signal amplitude of the domestic HDMI switcher chip by writing registers via the I2C bus. The interface can be configured by changing register parameters as required.

[0035] The main controller can read the currently configured display channel through the message, and control the corresponding channel indicator light through the I / O output interface to indicate the channel currently being displayed.

[0036] Example like Figure 1As shown, this embodiment uses two-stage cascaded MS9601A, with three MS9601A used in the first stage and one MS9601A used in the second stage, to achieve 8-channel HDMI signal input (HDMIIN1-HDMIIN8) and 1-channel HDMI signal output. The main controller writes the MS9601A chip register through the I2C instruction to achieve this. When a certain input signal is selected for output, the TMDS input of the channel is multiplexed to the output port TMDS channel through the internal 3-to-1 multiplexing of the MS9601A chip, the selected input port DDC interface is connected to the DDC interface of the output port, the HPD signal state of the selected input end is consistent with the HPD signal state of the output port, the unused port TMDS input and output are disconnected, the DDC channel is isolated, and the HPD is kept at a low level. The MS9601A chip can be cascaded by configuring different I2C addresses. The main control chip configures the address of the MS9601A chip by controlling the I2C bus to write the internal CHIPID register of the MS9601A chip.

[0037] MS9601A is a 3-input 1-output switch chip for HDMI signals, supporting a maximum signal rate of 3Gbps. and resolution HDMI input signal.

[0038] In order to adapt to cables of different lengths and qualities and ensure stable signal transmission, when parameters need to be adjusted, the equalizer at the HDMI input and the signal amplitude at the output can be adjusted through I2C interface chip programming.

[0039] like Figure 2 As shown, this embodiment converts HDMI signals into VGA signals and outputs them to an external display through the MS9291 chip. Specifically, the three pairs of data signals and one pair of clock signals of the HDMI signal output by the MS9601A chip, and the HPD signal are connected to the input end of the MS9291 chip, and the MS9291 chip outputs RGBHV and EDID signals VGA_SCL and VGA_SDA to the external display interface.

[0040] MS9291 is a low-cost, low-power semiconductor device that integrates an HDMI receiver and a 10-bit video digital-to-analog converter (DAC). It is mainly used to convert HDMI signals into VGA signal outputs, with a maximum supported conversion speed of 300MHz and supports SPDIF output. The HDMI receiver supports 1080P@60Hz, and is easy to use because it integrates MCU and EDID.

[0041] like Figure 3As shown, for 8-channel USB signals (composite USB mouse and USB keyboard are 1-channel USB signals), this embodiment uses 8 hub main chips FE1.1S to enhance the driving capability of USB signals, and then sends them to 2 groups of multi-channel analog switches CH444 for 4-choose-1 output. The output signal is sent to 1 RS2227XN for 2-choose-1 connection, and then sent to 1 chip FE1.1S to expand the USB signal into two channels and shape the USB signal before connecting to the keyboard and mouse. Among them, the 8 hub main chips FE1.1S are used to realize 8-channel USB2.0 signal input and output. The host USB signal can enhance the electromagnetic interference and anti-static capabilities through this chip, and enhance the USB driving capability.

[0042] CH444 is a DPQT low-resistance broadband bidirectional analog switch chip, including 2-way single-pole four-throw four-choice switches. The CH444 is used to control the level of the coding address IN1 and IN0 through the IO port of the microcontroller to realize the four-choice switching of the USB signal. The enable signal of the two CH444 chips is low and effective.

[0043] RS2227XN is a high-speed USB 2.0 (480-Mbps) 1:2 multiplexing / demultiplexing switch, which is a high-speed bipolar double-throw analog switch. The RS2227XN is used to realize the switching control of two USB signals, the output enable signal OE is grounded, and the output channel selection S is controlled by the IO interface of the microcontroller to realize high-speed switching of two USB signals.

[0044] FE1.1S is a master control IC for USB 2.0 HUB, providing 4 USB ports, with high performance, low power consumption and low cost. Due to its high performance, low power consumption and low cost, it is widely used in USB device expansion and connection solutions. The FE1.1S chip is used to realize the input expansion function of USB keyboard and mouse.

[0045] The main controller in this embodiment adopts the GD32F103XX series or other main control chips with I2C, network controller, CAN port, serial port, etc., and has functions such as key detection and processing, network control, LED indicator control, data communication, and issuing control instructions. The GD32F103XX series is a 32-bit general-purpose microcontroller (MCU) based on the ARM Cortex-M4 processor.

[0046] The main controller is responsible for receiving the switching control command from the external communication interface (RS485, RS232, CAN, Ethernet port), parsing and processing the control command after receiving it, and controlling the Figure 3The two-stage analog switch encoding address realizes the eight-choice channel connection, and connects the USB keyboard and mouse signal to the external host to realize operation control. The main controller writes the internal RX_PORT switching register of the secondary MS9601A chip through the I2C bus to realize the eight-choice output of the HDMI signal.

[0047] The switching command message format of the KVM signal is shown in Table 1. The KVM message header is 0xA5, 0x5A, the switching command word is 0x80, the channel selection data bit is 0x00, the value range is 0-7, identifying 1-8 channels, and can support extended data. Whether it is valid is a fixed value 0x01, and the check bit is 0x80 & the lower 8 bits of the data.

[0048] Table 1 KVM signal switching commands

[0049] The main controller initializes the internal network controller, configures the IP address, receives control commands sent by the external network, parses and processes network messages, and sends commands to the I2C channel to implement KVM switching.

[0050] Main controller real-time detection Figure 1 The key1-key8 switch button, when a key is triggered, obtains the key value through different IO ports, controls the corresponding analog switch corresponding channel selection and controls the corresponding display switching chip to work, and switches USB and HDMI signals.

[0051] The main controller can read the currently configured display channel through the KVM channel read command message. The message format is shown in Table 2. The KVM message header is 0xA5, 0x5A, the read channel command word is 0x40, the data bit is 0x00, and whether the data is valid is a fixed value of 0x01. The value of the data bit is obtained by parsing the return value to obtain the current display channel. This message is used to send the current display channel data to the external communication interface.

[0052] Table 2 KVM channel read commands

[0053] After the main control chip is initialized, the frequency of the input CLK is detected, and the equalization adjustment of the input HDMI signal and the amplitude adjustment of the output HMDI signal are achieved by setting the register RX receiving EQ value and TX output value of the MS9601A to meet the display signal adjustment requirements in different application environments. The RX input signal adjustment EQ frequency starting point adjustment, EQ eye height adjustment, high-frequency compensation point adjustment, and low-frequency gain adjustment are achieved by configuring the corresponding register values. The output adjustment adjusts the amplitude of the output signal, which can be achieved by adjusting the current value of the register. The larger the current value, the larger the amplitude. The adjustment range of the input data signal amplitude is 150mv-1200mv. The de-emphasis amplitude adjustment is mainly to reduce the amplitude of the low-frequency signal. The larger the register value, the larger the driving current, and the greater the reduction amplitude of the low-frequency signal. Two-stage de-emphasis processing can be achieved, and 3 pairs of data channels can be adjusted together. See the specific implementation case. Figure 4 .

[0054] like Figure 5 As shown, the present application proposes a reinforced KVM switch, which includes a main control unit, a power supply unit and an interface unit.

[0055] The main control unit is a KVM switch control board, which is used to collect key switches, receive commands sent by the network, serial port, and CAN port, parse the commands, control the internal KVM switch circuit selection, and realize KVM switching. The KVM switch control board uses domestic chips, single-chip microcomputers, etc., supports 8 groups of HDMI and USB signal inputs, 1 group of HDMI and USB signal outputs, and realizes 8-in-1 switching function.

[0056] The power supply unit is composed of an AC filter and an AC-DC module power supply to provide DC power supply for the subsequent stage. The AC-DC module power supply is used to provide 12V and 5V power supply for the subsequent stage, and the AC filter is used to filter the AC input signal to enhance the anti-interference ability.

[0057] The interface unit is mainly composed of an aviation connector, a switch, an indicator light, etc. The aviation connector is used to connect the AC power supply interface and HDMI, USB, management network port, serial port, and CAN port communication; the switch includes a power switch and a switch button switch; the indicator light includes a power indicator light and a switch button indicator light.

[0058] Based on the above, this application proposes a control method for an 8-port HDMI reinforced KVM switch, comprising the following steps: Step 1: Initialize the main controller network port, serial port, CAN port and I2C bus master mode; initialize the HDMI switch control chip I2C, write the chip address, initialize the internal register, turn off the TX output, detect the input signal clk frequency, set the RX receive EQ value and the TX output drive value to write to the register; Step 2: The main controller waits to receive the control command sent by the external communication interface (network port, serial port, CAN port), parses and processes the control message shown in Table 1, and obtains the display channel data information; the main controller detects the user's key in real time, obtains the key value when a key is triggered, and obtains the display channel data information. The key values ​​key1-key8 correspond to the current display channels 1-8; Step 3: The main controller obtains the display channel data and sends a command through the I2C bus to control the internal selection of the HDMI display switching chip. One HDMI switching chip has a high-resolution HDMI signal 3-input and 1-output switching display function. Through a two-level cascade method, it can output one HDMI signal from the specified channel of the 9-channel HDMI input signal; at the same time, the main controller I / O output interface controls the corresponding channel indicator to light up, indicating the channel currently being displayed; Step 4: The main controller writes the register of the domestic HDMI switch chip through the I2C bus to control the HDMI display signal input balance and output signal amplitude, and output the default value. This interface can change the specific configuration of parameters according to the specific application scenario; Step 5: The VGA signal conversion chip converts the HDMI output signal in step 3 into a VGA signal and outputs it to the external display device; Step 6: The main controller obtains the current display channel data in step 2 and controls the USB signal switching, as follows: 4 external host input USB composite signals (host USB mouse and keyboard signals are composited into 1 USB peripheral) are connected to the multi-channel analog two-channel single-pole four-throw analog switch for selection after signal adjustment through the USB HUB expansion chip, and the main controller IO interface outputs the coded address to control the multi-channel analog two-channel single-pole four-throw analog switch to select one of the four, and one of the adjusted input USB composite signals is connected to the input end of the high-speed bipolar double-throw analog switch; Step 7: The output signals of two groups of multi-channel analog two-channel single-pole four-throw analog switches are connected to the input end of the high-speed double-pole double-throw analog switch. The main controller controls the high-speed double-pole double-throw analog switch through the IO port to achieve 2-to-1 selection of the access signal, and finally achieve 8-to-1 selection of the external host USB signal. Step 8: The USB keyboard and mouse signals are connected to the downstream port of the USB HUB chip, and the upstream port of the USB HUB chip is connected to the host USB interface of the current display channel.

[0059] The main controller controls the input balance and output signal amplitude of the domestic HDMI switch chip by writing registers through the I2C bus, and writes default values ​​to the relevant registers when initializing according to the detected input CLK. When the display effect is not good, the register parameters can be changed according to the use environment for configuration. The specific control method is as follows: (1) Use an oscilloscope to collect the eye diagram of the HDMI signal output by each external host through the back end of a cable to determine the eye height, eye width, jitter, clock frequency, rise and fall time; (2) According to the eye width and eye height of the eye diagram, adjust the EQ equalization value, determine the EQ frequency starting point F1 and the high-frequency compensation frequency point F2, set a smaller register current value and load value, and adjust the eye height. 4 pairs of differential signals are adjusted together to reduce signal jitter and increase high-frequency components; (3) Adjust the low-frequency signal gain of the signal between F1 and F2, set a larger value to reduce the low-frequency gain, and make the rising and falling edges of the signal steeper; (4) Perform gain compensation on the frequencies after point F2, set a larger value, enhance high-frequency gain compensation, and prevent over-compensation; (5) For the first-level (near external host) chip, the TX output amplitude input terminal amplitude is limited to between 0.8V and 1.1V, and the register is set to prevent crosstalk and amplification of noise signals; for the second-level (near display) chip, the register is set to limit the output amplitude input terminal amplitude to between 1.0V and 1.2V; (6) De-emphasize the three pairs of differential signals and set the registers to reduce the amplitude of the low-frequency signal by no more than 20%.

[0060] Based on the method in the above embodiment, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method in the above embodiment.

[0061] Based on the method in the above embodiment, an embodiment of the present application provides a computer program product. When the computer program product runs on a processor, the processor executes the method in the above embodiment.

[0062] It is understandable that the processor in the embodiment of the present application may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0063] The method steps in the embodiments of the present application can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in random access memory (RAM), flash memory, read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, mobile hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC.

[0064] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted through the computer-readable storage medium. The computer instructions may be transmitted from a website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)), etc.

[0065] It should be understood that the various numerical numbers involved in the embodiments of the present application are only used for the convenience of description and are not used to limit the scope of the embodiments of the present application.

[0066] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. An 8-port HDMI reinforced KVM switch, characterized in that: include: Main controller, four HDMI switcher chips, VGA conversion chip, USB signal enhancement driver module, two sets of two-channel single-pole four-throw analog switches, high-speed double-pole double-throw analog switches and USB HUB expansion chip; among them, The main controller is used to control the channel gating of the HDMI switch chip through the I2C bus according to the display channel data information to realize multiple-choice-1 switching of the display signal, and control the channel gating of the two-channel single-pole four-throw analog switch through the IO interface to realize multiple-choice-1 switching of the USB signal; The four HDMI switcher chips are in a two-stage cascade structure, the first stage is composed of the first to third HDMI switcher chips, and the second stage is the fourth HDMI switcher chip, realizing 8-way HDMI input signals and 1-way HDMI output signal; the HDMI output signal is directly output to the display, or converted to a VGA signal by a VGA conversion chip and then output to the display; The USB signal enhancement driving module, two groups of two-channel single-pole four-throw analog switches, the high-speed double-pole double-throw analog switch and the USB HUB expansion chip are electrically connected in sequence, wherein the USB signal enhancement driving module enhances the 8-way USB signal and sends it to the two groups of two-channel single-pole four-throw analog switches for four-to-one output, the output signal is sent to the high-speed double-pole double-throw analog switch for two-to-one output, and is sent to the upstream port of the USB HUB expansion chip for USB signal expansion and shaping before outputting to the keyboard and mouse.

2. The reinforced KVM switch according to claim 1, characterized in that: The reinforced KVM switch reserves an external I2C interface; The I2C interface supports an external controller to program the HDMI switch chip register to implement the equalizer at the HDMI input end and the signal amplitude adjustment at the output end to meet the display signal adjustment requirements in different application environments.

3. The reinforced KVM switch according to claim 1, characterized in that: The USB signal enhancement driving module is composed of 8 USB HUB expansion chips, and each USB HUB expansion chip is responsible for shaping one USB signal.

4. The reinforced KVM switch according to claim 1, wherein: The main controller obtains display channel data information in any of the following ways: 1) Real-time detection of key switches, when a key is triggered, obtain the key value through different IO ports; 2) Receive the KVM switching command sent by the external communication interface and parse the command.

5. The reinforced KVM switch according to any one of claims 1 to 4, characterized in that: The main controller adopts GD32F103XX series or other main control chips with I2C, network controller, CAN port, and serial port, and has the functions of key detection processing, network control, LED indicator light control, data communication and issuing control instructions.

6. The reinforced KVM switch according to any one of claims 1 to 4, characterized in that: The HDMI switch chip is MS9601A, and the VGA conversion chip is MS9291.

7. The reinforced KVM switch according to claim 6, characterized in that: The main controller realizes the equalization adjustment of the input HDMI signal and the amplitude adjustment of the output HMDI signal by setting the register RX receiving EQ value and the TX output value of the MS9601A.

8. The reinforced KVM switch according to claim 7, characterized in that: The adjustment range of the input data signal amplitude is 150mv-1200mv, and the RX input signal adjustment includes: EQ frequency starting point adjustment, EQ eye height adjustment, high frequency compensation point adjustment and low frequency gain adjustment, which are achieved by configuring the corresponding register values.

9. The reinforced KVM switch according to claim 7, wherein: The output adjustment adjusts the amplitude of the output signal by adjusting the current value of the register. The larger the current value, the larger the amplitude.

10. The reinforced KVM switch according to any one of claims 1 to 4, characterized in that: The two-channel single-pole four-throw analog switch is CH444, the high-speed double-pole double-throw analog switch is RS2227XN, and the USB HUB expansion chip is a FE1.1S (SL2.1S) chip.

Images