CN110618949A

CN110618949A - KVM function card based on LPC bus

Info

Publication number: CN110618949A
Application number: CN201910821003.4A
Authority: CN
Inventors: 崔君宇
Original assignee: Tianjin Embedtec Co Ltd
Current assignee: Tianjin Embedtec Co Ltd
Priority date: 2019-09-02
Filing date: 2019-09-02
Publication date: 2019-12-27

Abstract

The invention discloses a KVM function card based on LPC bus, which comprises: the VPX interface module can realize the connection with the equipment with VPX corresponding interface, such as a PC; the switching module can realize switching of the multi-path input signals into one-path signals; the FPGA control module is used for finishing LPC bus communication and realizing the control of the switching module; the USB expansion module is used for realizing one path of USB expansion and two paths of USB; the power supply module is used for supplying power to different types of power supplies of the modules; the VPX interface module is connected with the switching module, the switching module is respectively connected with the FPGA control module and the USB extension module, and the FPGA control module is connected with the VPX interface module through an LPC bus. The invention has the advantages and beneficial effects that: the board card realizes the fast and stable switching of 8 paths of VGA signals and 8 paths of USB signals, greatly simplifies the hardware circuit design of the board card, reduces the fault rate of a system through simpler circuit design, and effectively improves the reliability of the system.

Description

KVM function card based on LPC bus

Technical Field

The invention relates to peripheral equipment of a PC (personal computer), in particular to KVM (keyboard video mouse) equipment for realizing the switching of a plurality of paths of VGA (video graphics array) and USB (universal serial bus) functions by an upper computer through an LPC (linear predictive coding) bus.

Background

The KVM realizes the control of a plurality of devices by utilizing a group of keyboard, display and mouse, and plays an important role in the aspects of scheduling monitoring and the like, thereby leading the management operation to be simple and greatly improving the efficiency. Currently, the KVM device used by us is generally implemented by a chip with a specific switching function. For example, most KVM devices that implement switching between VGA and USB are implemented by using a combination of a VGA switch chip and a USB switch chip. There are three problems with this approach: firstly, when the number of switching paths is very large, a multi-stage switch is needed for switching, in the prior art, a plurality of buses are generally connected to one switching chip, and then one path of bus signals are output, the switching switch chip with the specific function generally has few switching paths, and when the multi-stage switching is carried out, the integrity of the signals is poor; secondly, the diverter switch chip is produced by foreign manufacturers, which is not beneficial to realizing the localization; thirdly, hot key switching is not supported. In view of the wide application and excellent performance of the KVM device, the present invention designs a KVM function card based on LPC bus, solving the above three problems.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a KVM function card based on an LPC bus.

In order to achieve the purpose, the technical scheme of the invention is as follows:

an LPC bus based KVM function card comprising: the VPX interface module can realize the connection with the equipment with VPX corresponding interface, such as a PC; the switching module can realize switching of the multi-path input signals into one-path signals; the FPGA control module is used for finishing LPC bus communication and realizing the control of the switching module; the USB expansion module is used for realizing one path of USB expansion and two paths of USB; the power supply module is used for supplying power to different types of power supplies of all modules of the system; the VPX interface module is connected with the switching module, the switching module is respectively connected with the FPGA control module and the USB extension module, and the FPGA control module is connected with the VPX interface module through an LPC bus.

The FPGA control module comprises an LPC control unit, a switching control unit, a read-write control unit and a data storage unit, wherein the LPC control unit, the switching control unit and the read-write control unit are sequentially connected, and the data storage unit is connected with the read-write control unit.

The LPC control unit realizes communication between the FPGA and an upper computer through an LPC bus; the switching control unit realizes that the FPGA controls the switching module; the read-write control unit realizes the time sequence control of data read-write interaction of the LPC bus control unit and the read-write control of the data storage unit; the data storage unit completes buffer storage of communication data.

The switching module comprises a VGA switching unit and a USB switching unit, and the VGA switching unit switches 8 paths of input VGA signals transmitted by the VPX interface module into one path of VGA signal; the USB switching unit switches 8 paths of USB signals transmitted by the VPX interface module into one path of USB signals.

The VPX interface module comprises a VPX connector.

The USB expansion module is connected with the switching module and expands one path of USB output by the USB expansion module into two paths of USB signals through the USB expansion module.

The power supply module comprises a power supply conversion chip and realizes voltage conversion from +12V to +5V and + 3.3V.

The invention has the advantages and beneficial effects that: the board card realizes the fast and stable switching of 8 paths of VGA signals and 8 paths of USB signals, greatly simplifies the hardware circuit design of the board card, reduces the fault rate of a system through simpler circuit design, and effectively improves the reliability of the system.

Drawings

FIG. 1 is a block diagram of a system design of a KVM function card based on an LPC bus according to the present invention;

FIG. 2 is a schematic structural diagram of the FPGA module in FIG. 1;

fig. 3 is a schematic structural diagram of the switching module in fig. 1.

Detailed Description

The invention is described in further detail below with reference to the figures and the detailed description.

As shown in fig. 1, a KVM function card based on LPC bus includes: the VPX interface module can realize the connection with the equipment with VPX corresponding interface, such as a PC; the switching module can realize switching of the multi-path input signals into one-path signals; the FPGA control module is used for finishing LPC bus communication and realizing the control of the switching module; the USB expansion module is used for realizing one path of USB expansion and two paths of USB; the power supply module is used for supplying power to different types of power supplies of all modules of the system; the VPX interface module is connected with the switching module, the switching module is respectively connected with the FPGA control module and the USB extension module, and the FPGA control module is connected with the VPX interface module through an LPC bus.

As shown in fig. 2, the FPGA control module specifically selects a MAX10 series 10M08SCU169I7 chip of ALTERA corporation, and includes an LPC control unit, a switching control unit, a read-write control unit, and a data storage unit, where the LPC control unit, the switching control unit, and the read-write control unit are sequentially connected, and the data storage unit is connected to the read-write control unit.

As shown in fig. 3, the switching module includes a VGA switching unit and a USB switching unit, and the VGA switching unit switches 8 paths of input VGA signals transmitted from the VPX interface module into one path of VGA signal; the USB switching unit switches 8 paths of USB signals transmitted by the VPX interface module into one path of USB signals.

The basic principle of the invention is to split 8-channel input VGA and USB signals into single signals respectively for switching processing, and a switching chip selects a common 8-to-1 multi-channel output selector in the market. In order to guarantee signal integrity, impedance control needs to be performed when the PCB is wired, integrity of an impedance reference layer is guaranteed, and each split signal needs to be wrapped and protected by a ground wire. The invention is suitable for switching a plurality of data buses, is not limited to 8-to-1 switching functions, for example, a 16-to-1 multiplexer can be selected to switch a 16-to-1 input bus to a 1-to-1 output bus, and the like.

The VPX interface module comprises a VPX connector.

The USB expansion module is connected with the switching module, specifically, a USB2514BI chip of SMSC company is selected, and one path of USB output by the USB expansion module is expanded into two paths of USB signals through the USB expansion module.

The power supply module adopts a power supply conversion chip TPS56428 chip to realize voltage conversion from +12V to +5V and + 3.3V.

The testing method of the invention comprises the following steps:

the method comprises the following steps: and inserting the KVM function card of the VPX interface into the VPX interface of the test computer, and connecting the mouse and the keyboard to the test computer.

Step two: and electrifying the test computer, starting up the test computer and entering an operating system.

Step three: the VGA and the USB can be normally switched to the corresponding channel by using the upper computer to control the switching or the keyboard hot key switching.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. An LPC bus based KVM function card comprising:

the VPX interface module can realize the connection with the equipment with VPX corresponding interface, such as a PC;

the switching module can realize switching of the multi-path input signals into one-path signals;

the FPGA control module is used for finishing LPC bus communication and realizing the control of the switching module;

the USB expansion module is used for realizing one path of USB expansion and two paths of USB;

the power supply module is used for supplying power to different types of power supplies of the modules;

the VPX interface module is connected with the switching module, the switching module is respectively connected with the FPGA control module and the USB extension module, and the FPGA control module is connected with the VPX interface module through an LPC bus.

2. The LPC bus-based KVM function card of claim 1, wherein: the FPGA control module comprises an LPC control unit, a switching control unit, a read-write control unit and a data storage unit, wherein the LPC control unit, the switching control unit and the read-write control unit are sequentially connected, and the data storage unit is connected with the read-write control unit.

3. The LPC bus-based KVM function card of claim 2, wherein: the LPC control unit realizes communication between the FPGA and an upper computer through an LPC bus; the switching control unit realizes that the FPGA controls the switching module; the read-write control unit realizes the time sequence control of data read-write interaction of the LPC bus control unit and the read-write control of the data storage unit; the data storage unit completes buffer storage of communication data.

4. The LPC bus-based KVM function card of claim 1, wherein: the switching module comprises a VGA switching unit and a USB switching unit, and the VGA switching unit switches 8 paths of input VGA signals transmitted by the VPX interface module into one path of VGA signal; the USB switching unit switches 8 paths of USB signals transmitted by the VPX interface module into one path of USB signals.

5. The LPC bus-based KVM function card of claim 1, wherein: the VPX interface module comprises a VPX connector.

6. The LPC bus-based KVM function card of claim 1, wherein: the USB expansion module is connected with the switching module and expands one path of USB output by the USB expansion module into two paths of USB signals through the USB expansion module.

7. The LPC bus-based KVM function card of claim 1, wherein: the power supply module comprises a power supply conversion chip and realizes voltage conversion from +12V to +5V and + 3.3V.