CN100346271C - Method and device for two-way communication between virtual PS/2 apparatus and host machine - Google Patents

Method and device for two-way communication between virtual PS/2 apparatus and host machine Download PDF

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CN100346271C
CN100346271C CNB2004100307020A CN200410030702A CN100346271C CN 100346271 C CN100346271 C CN 100346271C CN B2004100307020 A CNB2004100307020 A CN B2004100307020A CN 200410030702 A CN200410030702 A CN 200410030702A CN 100346271 C CN100346271 C CN 100346271C
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data
equipment
mouse
main frame
keyboard
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CN1677325A (en
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何彦
安岩
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Lenovo Beijing Ltd
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Lenovo Beijing Ltd
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Abstract

The present invention relates to a method and a device for communicating between a virtual PS/2 device and a host computer. The method comprises: 1) the procedure of a single-chip computer at the PS/2 device end for virtual communication between a host computer and a PS/2 device; 2) a single-chip computer at the host computer end for virtual communication between the host computer and the PS/2 device. The device comprises the PS/2 device and the host computer, and in addition, the PS/2 device end also comprises a first single-chip computer which is used for interacting an initialization signal of a PS/2 device for the virtual PS/2 device and the host computer; the device initializes the PS/2 device, and detects and processes a PS/2 protocol signal at the PS/2 device end. The host computer end also comprises a second single-chip computer which is used for interacting to an initialization signal of a PS/2 device for the virtual PS/2 device and the host computer, the host computer virtually initializes the PS/2 device, and detects and processes a PS/2 protocol signal at the host computer end. Because of using the single-chip computer to virtual communication between the PS/2 device and the host computer, the present invention can support no device start of the host computer and the hot plug of the PS/2 device; can adopt an RS485 protocol communication mode to improve the communication distance between the PS/2 device and the host computer.

Description

The method and the device of two-way communication between virtual PS/2 equipment and main frame
Technical field
The present invention relates to the computer communication technology field, refer to realize in a kind of computing machine the method and the device of virtual communication especially.
Background technology
Computing machine is the product of modern society's high speed development, its appearance has not only made things convenient for people's life, and improved people's work efficient, and PS/2 equipment as the important subsidiary function equipment of computing machine its by PS/2 protocol interface and main-machine communication, described PS/2 protocol interface is meant the interface of working out according to the PS/2 consensus standard, PS/2 equipment such as keyboard, mouse can be linked to each other with main frame and realizes main frame and the communication each other of PS/2 equipment by the PS/2 protocol interface.
In recent years, development along with some special application fields, development as server management system, communication between PS/2 equipment and main frame there is new requirement again, with KVM (keyboard, display, mouse) system is example, and it is by the configuration of appropriate keyboard, mouse and display, the security of realization system and network, manageability, and improve managerial personnel's work efficiency, saving machine room area, reduce the TCO (total cost of ownership) of network server system.In the KVM system, even under the situation that does not connect PS/2 equipment, also require main frame to start smoothly, require PS/2 equipment can support hot plug simultaneously, promptly not with when main frame links to each other, can be when powering on PS/2 equipment such as auto-initiation keyboard and mouse, and it is provided with some relevant parameters.In addition, for server management system, often require energy telecommunication between main frame and the PS/2 equipment, the communication distance between existing PS/2 equipment and main frame has only tens meters, can't realize long-distance transmissions.
In order to solve the problems of the technologies described above, prior art realizes by the PS/2 signal that transmits between PS/2 equipment and main frame directly being carried out difference processing.Concrete, because the PS/2 signal is a digital signal, its frequency is between 10~30KHz, send out after can handling above-mentioned PS/2 signal direct differential earlier, differential signal is with the difference between two physical quantitys of a numeric representation, because differential signal is to change with the difference between two signals again, therefore, compare with benchmark " " signal that is as the criterion and sends out, its stability is better, transmitting range is also far away relatively.
But in the reality, main frame and PS/2 equipment room are according to the bi-directional synchronization serial protocol communication, be that PS/2 equipment can send data to main frame, main frame also can send data to PS/2 equipment, simply the signal that transmits is carried out difference processing if only be, error is bigger, not only do not reach and realize main frame and the data double-way communication of PS/2 equipment and the purpose of telecommunication, and the required chip of difference processing is more, the cost height, volume is big, therefore, and impracticable, can not realize the hot plug of the no device start and the support PS/2 equipment of main frame.
Summary of the invention
Can not realize that in order to solve prior art main frame does not have the problem of device start, the invention provides the method and the device of two-way communication between a kind of virtual PS/2 equipment and main frame, can realize that main frame does not have device start, and support the hot plug of PS/2 equipment.
For addressing the above problem, the method of two-way communication comprises between virtual PS/2 equipment provided by the invention and main frame: the 1) step and 2 of PS/2 equipment end fictitious host computer and the PS/2 devices communicating) step of virtual PS/2 equipment of host side and main-machine communication, and described step 1) comprises:
11) PS/2 equipment is connected with first microprocessor, described first microprocessor is virtual to be main frame and the mutual PS/2 device initialize of PS/2 equipment signal, and the described PS/2 equipment of initialization;
12) described first microprocessor is virtual for main frame detects whether the PS/2 protocol signal is arranged, and if any then carrying out respective handling, otherwise continues to detect;
Described step 2) comprising:
21) main frame is connected with second microprocessor, described second microprocessor is virtual to be PS/2 equipment and the mutual PS/2 device initialize of main frame signal, and by the virtual initialization PS/2 of described main frame equipment;
Whether 22) described second microprocessor is virtual has the PS/2 protocol signal for the PS/2 Equipment Inspection, if any then carrying out respective handling, otherwise continues to detect.
Wherein, adopt the communication of RS485 mode between described first microprocessor and described second microprocessor.
Wherein, described PS/2 equipment can be keyboard and/or mouse.
In addition, described step 12) further comprises:
Whether a1) described first microprocessor is virtual has data for main frame detects the keyboard mouth, if any then reading a byte data from the keyboard mouth, and sends by serial ports, enters step a2 then), as not detecting data, then directly enter step a2);
Whether have data, as detect the mouse mouth data are arranged if a2) detecting the mouse mouth, then read a byte data from the mouse mouth, and send by serial ports, enters step a3 then), as not detecting data, then directly enter step a3);
Whether have data, as detect serial ports data are arranged if a3) detecting serial ports, then described data are sent to the corresponding interface, returns step a1) continue to detect, as not detecting data, then directly get back to a1) continue to detect;
Described step 22) further comprise:
Whether b1) described second microprocessor is virtual has data for the keyboard mouth of the described main frame of PS/2 Equipment Inspection, read a byte data if any keyboard mouth then, and send, enter step b2 then) by serial ports from described main frame, as not detecting data, then directly enter step b2);
B2) whether the mouse mouth that detects described main frame has data, reads a byte data if any the mouse mouth from described main frame then, sends by serial ports, enters step b3 then), as not detecting data, then directly enter step b3);
Whether have data, as detect serial ports data are arranged if b3) detecting serial ports, then described data are sent to the corresponding interface, goes back to step b1) continue to detect data, as not detecting data, then directly get back to b1) continue to detect.
According to a further aspect in the invention, the device of a kind of virtual PS/2 equipment and inter-host communication comprises PS/2 equipment and main frame, and it also comprises in the PS/2 equipment end:
First microprocessor, its I/O mouth links to each other with the PS/2 protocol interface of PS/2 equipment, is used for the initializing signal of fictitious host computer and the mutual PS/2 equipment of PS/2 equipment, and the PS/2 protocol signal of the described PS/2 equipment of initialization and detection and processing PS/2 equipment end;
Also comprise in host side:
Second microprocessor, link to each other with first microprocessor, its I/O mouth links to each other with main frame PS/2 protocol interface, is used for the initializing signal of virtual PS/2 equipment and the mutual PS/2 equipment of main frame, and by the PS/2 protocol signal of main frame virtual initialization PS/2 equipment and detection and processing host end.
Optimize, described PS/2 equipment end also comprises a RS485 circuit, a described RS485 circuit is connected with first microprocessor serial ports I/O pin by transmissions/receiving port, is used for that the asynchronous serial signal that first microprocessor is exported is carried out corresponding difference processing and sends to main frame then or the differential signal that main frame is brought in is reduced processing and send to first microprocessor.
Described host side also comprises the 2nd RS485 circuit, link to each other with a RS485 circuit, and be connected with the second microprocessor serial ports I/O pin by transmissions/receiving port, be used for that the asynchronous serial signal that second microprocessor is exported is carried out corresponding difference processing and send to PS/2 equipment then or the differential signal that PS/2 equipment is brought in is reduced processing and send to second microprocessor.
Wherein, described PS/2 equipment can be keyboard and/or mouse.
Compared with prior art, the present invention has following advantage:
1, the present invention passes through to add the operation and the order of a microprocessor fictitious host computer and/or PS/2 equipment, thereby realizes the hot plug of the no device start and the support PS/2 equipment of main frame.
2, because the present invention adopts the virtual PS/2 agreement of microprocessor to realize communicating by letter between PS/2 equipment and main frame, adopt the communication of RS485 protocol mode between the microprocessor of the microprocessor of host side and PS/2 equipment end, can improve the transmitting range of PS/2 signal greatly, thereby realize the telecommunication of main frame and PS/2 equipment.
Description of drawings
Fig. 1 a is the process flow diagram of PS/2 equipment end virtual communication in virtual PS/2 equipment of the present invention and the inter-host communication method specific embodiment;
Fig. 1 b is the process flow diagram of host side virtual communication in virtual PS/2 equipment of the present invention and the inter-host communication method specific embodiment;
Fig. 2 a is the process flow diagram of PS/2 equipment end microprocessor processes data in virtual PS/2 equipment of the present invention and the inter-host communication method;
Fig. 2 b is the process flow diagram of host side microprocessor processes data in virtual PS/2 equipment of the present invention and the inter-host communication method;
Fig. 3 is that the device of virtual PS/2 equipment of the present invention and inter-host communication is formed structural drawing;
Fig. 4 is the composition structural drawing behind the adding RS585 circuit in the described device of Fig. 3;
Fig. 5 a is PS/2 equipment of the present invention equipment end chip connection diagram when being keyboard/mouse;
Fig. 5 b is PS/2 equipment of the present invention host side chip connection diagram when being keyboard/mouse;
Fig. 6 is the process flow diagram that sends a byte data in the device formed of Fig. 5 a~Fig. 5 b to main frame;
Fig. 7 sends each inferior program flow diagram of data separately in the flow process of Fig. 6;
Fig. 8 is the process flow diagram that reads a byte data in the device formed of Fig. 5 a~Fig. 5 b from the PS/2 protocol interface of main frame;
Fig. 9 is each an inferior program flow diagram of reading of data among Fig. 8;
Figure 10 writes the process flow diagram of a data byte to equipment end in the device formed of Fig. 5 a~Fig. 5 b;
Figure 11 is the process flow diagram that the slave unit end reads a data byte in the device formed of Fig. 5 a~Fig. 5 b;
Figure 12 is each an inferior program flow diagram of reading of data in the flow process of Figure 11.
Embodiment
Fig. 1 a and Fig. 1 b are the process flow diagrams of virtual PS/2 equipment of the present invention and inter-host communication method preferred embodiment, the flow process of PS/2 equipment end virtual communication and the flow process of host side virtual communication are shown respectively, in order to realize the communication process between virtual PS/2 equipment and main frame, all added microprocessor in PS/2 equipment end and host side among the present invention, described microprocessor can be realized by single-chip microprocessor MCU, following indication single-chip microcomputer if no special instructions, all refer to microprocessor, the effect that adds described microprocessor mainly contains 2 points: 1, at PS/2 equipment end fictitious host computer supporting the hot plug of PS/2 equipment, and with the host side interactive signal; 2, at the virtual PS/2 equipment of host side supporting the no device start of main frame, and with PS/2 equipment end interactive signal.
Shown in Fig. 1 a and Fig. 1 b, described virtual PS/2 equipment and inter-host communication method comprise the step of PS/2 equipment end fictitious host computer and PS/2 devices communicating and the step of virtual PS/2 equipment of host side and main-machine communication, referring to Fig. 1 a, the virtual communication flow process of described PS/2 equipment end may further comprise the steps earlier:
In step 101 described PS/2 equipment is connected with single-chip microcomputer, described single-chip microcomputer is virtual to be main frame and the mutual PS/2 device initialize of PS/2 equipment signal, and the described PS/2 equipment of initialization;
According to the content of PS/2 agreement, at host-initiated or when newly inserting PS/2 equipment, need initialization PS/2 equipment with the state that detects PS/2 equipment and the PS/2 apparatus operating parameters is set so that can with main-machine communication.Therefore, in order to support the hot plug of PS/2 equipment, the MCU that adds among the present invention can fictitious host computer, when PS/2 equipment re-powers, it is carried out initialization process, this is well suited in the server management system, particularly in the system as KVM, with the configuration realization better managed of economy;
After to the PS/2 device initialize, whether further virtual have the PS/2 signal for main frame detects the PS/2 equipment end, as detected the PS/2 protocol signal, then carries out respective handling, handles the back and continue detection at the described single-chip microcomputer of step 102;
The communication of PS/2 equipment end relates generally to the PS/2 protocol signal that detects each PS/2 interface, and processing and host side information is mutual, described single-chip microcomputer is virtual be main frame with the PS/2 device initialize after, the further still virtual PS/2 protocol signal that each PS/2 equipment is sent for main frame sends to main frame, perhaps receives the signal that main frame sends and gives PS/2 equipment to carry out corresponding operation.
Shown in figure 1b, corresponding with above-mentioned PS/2 equipment end, the virtual communication flow process of host side may further comprise the steps:
In step 103 main frame is linked to each other with single-chip microcomputer, described single-chip microcomputer is virtual to be PS/2 equipment and the mutual PS/2 device initialize of main frame signal, and by the virtual initialization PS/2 of described main frame equipment;
As previously mentioned, according to the content of PS/2 agreement, need initialization PS/2 equipment before the host-initiated, in order to support the no PS/2 device start of host side, virtual by described single-chip microcomputer is PS/2 equipment and the relevant signal of the mutual PS/2 device initialize of main frame, and realizes virtual initialization PS/2 equipment;
Finish at step 104PS/2 device initialize, whether described single-chip microcomputer is then virtual has the PS/2 protocol signal for PS/2 monitoring of equipment host side, if having, then carries out respective handling, otherwise continues monitoring;
Similar with step 102, the mutual PS/2 signal of the single-chip microcomputer of main frame of this step and virtual PS/2 equipment, described single-chip microcomputer is virtual to be PS/2 equipment, and receive the PS/2 protocol signal that the PS/2 equipment end is sent, hand to main frame then, handle accordingly according to described signal by main frame, perhaps receive the signal that main frame is sent, and be transmitted to PS/2 equipment.
The foregoing description can be realized the virtual communication process between PS/2 equipment and main frame, and the system as KVM, not only require host side can realize not having PS/2 device start and PS/2 equipment end support hot plug, the communication distance that also need improve PS/2 equipment and main frame of You Huaing more, for this reason, can change the communication mode between PS/2 equipment and main frame, adopt the RS485 protocol mode to carry out communication between the single-chip microcomputer of for example described PS/2 equipment end and the single-chip microcomputer of host side, compare the mode of original PS/2 equipment and the direct communication of main frame, adopt the communication of RS485 mode that communication distance is increased greatly between the single-chip microcomputer, realize long-distance transmissions, this in server management system of great use, particularly to the such system of KVM, only depend on signal simply to carry out difference processing and be difficult to realize long-distance transmissions to transmission, above-mentioned employing RS485 protocol mode communication, again the signal that transmits between PS/2 equipment and main frame is carried out difference processing, transmission range will improve a lot on original basis, and the stability of signal is also better, certainly, because PS/2 equipment and main frame communicate by single-chip microcomputer, the telecommunication mode can also adopt other modes, as adopting 422 agreement communication modes etc., transmission range is all far away.
Further narration method of the present invention, above-mentioned PS/2 equipment refers to meet the equipment of PS/2 consensus standard, each other by the communication of PS/2 protocol interface, has 4 pins to link to each other between PS/2 equipment and the main frame: power supply ground ,+5V, data line and clock line.Main frame provides+the 5V power supply, and the ground of PS/2 equipment is connected to the power supply ground of main frame.Because data line and clock line all are open-collector, therefore, they keep high level usually and are easy to pull down to ground (logical zero), with PS/2 equipment is that keyboard and mouse are example, any equipment that is connected to the PS/2 protocol interface of keyboard, mouse or main frame needs a big pull-up resistor on clock line and data line, by described pull-up resistor, reset just drags down line (being low level), and (being high level) just drawn high line in set.
The present invention adopts the virtual PS/2 agreement of single-chip microcomputer for the process of the virtual communication of realizing PS/2 equipment end and host side, will be that keyboard/mouse is that example describes with PS/2 equipment below, at first simply describes the agreement of keyboard/mouse and main-machine communication:
In the communication, keyboard and mouse transmit data according to the bi-directional synchronization serial protocol, be to send out a pulse on the clock line, the one digit number that sends on the data line is according to just being read into, keyboard and mouse can send data to main frame, and main frame also can send data to keyboard/mouse, but main frame always has right of priority on bus, and it can at any time suppress the communication (only need drag down clock line and get final product) from keyboard/mouse.Send to the data of main frame from keyboard/mouse and be read at the negative edge of clock signal (clock signal by hypermutation to low), the data that send to keyboard/mouse from main frame are read in rising edge of clock signal (clock signal is by the low height that changes to).But no matter the direction of communication how, always the keyboard/mouse clocking.
For the communication of main frame, mainly follow following principle to keyboard/mouse:
If main frame will send data, then need allow the keyboard/mouse clocking earlier, also promptly at first clock line and data line be set to the state of " request sends ", concrete operations are as follows:
Suppress the communication that keyboard/mouse is brought in by drop-down clock line at least 100 microseconds;
Use " request sends " by drop-down data line, discharge clock line then.
For the communication of keyboard/mouse, mainly follow following principle to main frame:
At first check clock signal, under the normal condition, data line and clock line all are open-collector structure (maintenance high level), are high level if be checked through clock signal, and then keyboard/mouse can transmit data; If not, be main frame and suppress communication, must any data that will send of buffer memory up to the control that regains bus (generally keyboard has the buffer area of 16 bytes, and mouse is last packet that will send of buffer memory only then).
Above-mentioned communication protocol to keyboard/mouse and main frame has been carried out simple description, among the present invention to above-mentioned protocol processes process by the software control chip microcontroller, flow process to software control describes below, please see Figure shown in the 2a, software control data treatment scheme with PS/2 equipment end MCU describes earlier, described MCU is mainly used in fictitious host computer, may further comprise the steps:
At step 201MCU electrification reset, fictitious host computer is to keyboard and mouse initialization;
Finish in step 202 initialization, whether described MCU detects the keyboard mouth data, reads in a byte data if any then entering step 203 from the keyboard mouth, add the upper keyboard identification code, send, enter step 204 then by serial ports, as not detecting data, then directly enter step 204;
Detect whether data of mouse mouth at step 204MCU, if any, then enter step 205 and read in a byte data from the mouse mouth, add the mouse identification code, send by serial ports, enter step 206 then, as not detecting data, then directly enter step 206;
Detect serial ports at step 206MCU whether data are arranged, if any, then enter step 207 and judge it is keyboard data or mouse data by identification code, then described data are delivered to corresponding interface, forward step 202 again to and begin to detect, continue to detect data as then directly not getting back to step 202.
Above-mentioned identification code is an identification information that adds to data when sending, be used to distinguish data that distinct interface sends so that correct transmission and reception, data as keyboard mouth and the transmission of mouse mouth, can before data, add 00 and 01 difference respectively, also have multiple variation in the reality, do not giving unnecessary details here.
The software control data treatment scheme of host side MCU below, shown in figure 2b, described MCU is mainly used in dummy keyboard/mouse, comprises following step:
At step 208MCU electrification reset, cooperate main frame dummy keyboard/mouse initialization;
Whether the keyboard mouth that detects main frame at step 209MCU has data, if any data, because single-chip microcomputer is virtual to be keyboard, when main frame sends data to keyboard, described single-chip microcomputer detects the keyboard mouth has data then to enter the data that the first dummy keyboard reception of step 210 main frame is sent, add the upper keyboard identification code then, send by serial ports, described identification code principle is the same, below no longer carefully state, be sent completely, enter step 211, as not detecting data, then directly enter step 211 at described keyboard mouth;
Whether the mouse mouth that detects main frame at step 211MCU has data, the same step, because the single-chip microcomputer virtual mouse, when main frame sends data to mouse, described single-chip microcomputer detects the mouse mouth data, then enter the first virtual mouse of step 212 and receive the data that main frame is sent, add the mouse identification code then, send by serial ports, be sent completely, enter step 212,, then directly enter step 213 as not detecting data at the mouse mouth;
Detect serial ports at step 213MCU whether data are arranged, if any, enter step 214 and judge that according to identification code described data are data that the data sent of keyboard or mouse are sent, the identification code sign is the data of sending from keyboard as described, then described data is mail to the keyboard mouth of main frame, and vice versa, be sent completely, return step 209 and continue to detect data,, then directly get back to step 209 and continue to detect data as not detecting data at described serial ports.
Continue narration the present invention, realize the device of virtual PS/2 equipment of the present invention and inter-host communication, please form structural drawing referring to this device shown in Figure 3, described device comprises PS/2 equipment 301 and main frame 302, also comprises in the PS/2 equipment end in addition:
First single-chip microcomputer 303, its I/O mouth links to each other with PS/2 equipment 301PS/2 protocol interface, the initializing signal that is used for fictitious host computer 302 and PS/2 equipment 301 mutual PS/2 equipment 301, and the PS/2 protocol signal of the described PS/2 equipment 301 of initialization and detection and processing PS/2 equipment end;
Also comprise in host side:
Second singlechip 304, link to each other with first single-chip microcomputer 303, its I/O mouth links to each other with main frame 302PS/2 protocol interface, the initializing signal that is used for virtual PS/2 equipment 301 and main frame 302 mutual PS/2 equipment 301, and by the PS/2 protocol signal of main frame 302 virtual initialization PS/2 equipment 301 and detection and processing host end.
Two single-chip microcomputers of above-mentioned adding are mainly realized being provided with for function, during actual enforcement, can close and be made as one, but in order to improve the communication distance of PS/2 equipment and main frame, consider that the PS/2 equipment end links to each other by single-chip microcomputer, therefore can between described single-chip microcomputer, adopt the communication modes of RS485 agreement, please refer to Fig. 4, add a RS485 circuit 401 (might as well be called a RS485 circuit) in described PS/2 equipment end, described RS485 circuit 401 is connected with the first microcontroller serial port I/O pin by transmissions/receiving port, is used for that the asynchronous serial signal that first single-chip microcomputer is exported is carried out corresponding difference processing and sends to main frame then or the differential signal that host side is sent is reduced processing and send to first single-chip microcomputer;
Corresponding, also add a RS485 circuit 402 (might as well be called the 2nd RS485 circuit) in host side, link to each other with a RS485 circuit 401, and be connected with second singlechip 304 serial ports I/O pin by transmission/receiving port, be used for the asynchronous serial signal of second singlechip output is carried out corresponding difference processing, send to PS/2 equipment then or the differential signal that the PS/2 equipment end is sent reduced and handle and send to second singlechip.
Further specify described device, be keyboard and mouse with PS/2 equipment below, described single-chip microcomputer adopts 8 single-chip microcomputer PIC16C73 of MICRCHIP, described RS485 circuit is that half-duplex RS-485 communication chip MAX3486 is that example describes, described keyboard/mouse all comprises the clock line (CLK) of I/O clock signal and the data line (DAT) of I/O data, and described PIC16C73 comprises that I/O mouth RA0~RA3 is used for input/output signal, comprise that asynchronous serial port RC6~RC7 is used for serial transmission/received signal, comprise that also the pin RC4~RC5 of I/O high-low level is used to control transmission/accepting state of MAX3486, and described MAX3486 comprises the pin D1/R0 of transmission/reception, pin/RE that the asynchronous serial port Data Receiving enables (low level is effective), and the asynchronous serial port data send the pin DE (low level is effective) that enables, the pin A that also comprises reception/transmission differential signal, B
Still be described from the structure that connects to form of keyboard/mouse end and host side respectively below, please connect to form structural drawing referring to the keyboard/mouse end chip shown in Fig. 5 a, clock line (the K-CLK of keyboard and mouse, M-CLK) and data line (K-DTA, M-CLK) link to each other with I/O mouth RA0~RA3 of PIC16C73 respectively, so that the PS/2 signal of described PIC16C73 fictitious host computer and keyboard/mouse interactive keyboard and mouse (comprising clock and data-signal), described PIC16C73 transmission/reception pin RC6~RC7 links to each other with the pin R0/D1 of reception/transmission of MAX3486, MAX3486 is exported in the keyboard serial of above-mentioned I/O mouth input, so that after the MAX3486 difference processing by A, the B pin sends host side to, perhaps with A, the differential signal that the host side that the B pin receives is sent, after reduction is handled, by sending mouthful D1 the PS/2 signal that reduces is sent to PIC16C73, export to keyboard and/or mouse by described RA0~RA3 again, carry out corresponding operation by described keyboard or mouse at last.
Fig. 5 b is depicted as the host side chip and connects to form structural drawing, corresponding with the keyboard/mouse end, the MAX3486 that host side links to each other with the keyboard/mouse end, by A, the PS/2 signal of the process difference processing that B pin reception keyboard/mouse is sent, and MAX3486 is still by link to each other with the RC6/RC7 of PIC16C73 PS/2 signal after the mutual reduction of R0/D1, its asynchronous serial port data transmission/reception enables pin DE and links to each other with the R4/R5 of PIC16C73 with/RE (low level is effective), so that described PIC16C73 control MAX3486 serial transmission/reception PS/2 signal, different with the keyboard/mouse end, I/O mouth RA0~RA3 of described PIC16C73 links to each other with the keyboard/mouse mouth of host side, so that the PS/2 signal of dummy keyboard/mouse and main frame interactive keyboard/mouse, the course of work of the course of work of host side said chip and keyboard/mouse end is similar, repeats no more here.
In addition, available common netting twine links to each other between the described MAX3486 chip of host side and equipment end, and both economical, transmission range is also far away, also can adopt other line to connect, as linking to each other with CAT5E UTP cable.
Realize that with host side dummy keyboard/mouse the host-initiated of on-keyboard/mouse and the process of follow-up work further specify above-mentioned device below, because the power supply of host side is from the PS/2 mouth, therefore, in the time of start, single-chip microcomputer PIC16C73 is electrification reset also, single-chip microcomputer begins dummy keyboard and host communication, and the KEYBOARD of the following stated refers to the keyboard that single-chip microcomputer is virtual, and communication process is summarized as follows:
KEYBOARD:AA; Power-on self-test passes through
HOST:ED; The order of the state of some pilot lamp on the indication keyboard
KEYBOARD:FA; Keyboard is replied
HOST:00; Close all LED
KEYBOARD:FA; Keyboard is replied
HOST:F2; Read the ID of keyboard
KEYBOARD:FA, AB; Keyboard is replied, and adds first byte of ID
HOST:ED; The order of the state of some pilot lamp on the indication keyboard
KEYBOARD:FA; Keyboard is replied
HOST:02; Open the NUMLOCK lamp
KEYBOARD:FA; Keyboard is replied
HOST:F3; Sending a byte in this order back comes the definition machine to play speed and time-delay
KEYBOARD:FA; Keyboard is replied
HOST:20; Machine is beaten speed: 30 times/second, machine is played time-delay: 500MS
KEYBOARD:FA; Keyboard is replied
HOST:F4; Enable keyboard
KEYBOARD:FA; Keyboard is replied
HOST:F3; Sending a byte in this order back comes the definition machine to play speed and time-delay
KEYBOARD:FA; Keyboard is replied
HOST:00; Machine is beaten speed: 30 times/second, machine is played time-delay: 250MS
The above-mentioned initialization procedure that cooperates the main frame dummy keyboard by the PIC16C73 dummy keyboard, in this process, self check was finished after first " AA " expression that the PIC16C73 dummy keyboard sends powered on, if do not send this sign indicating number, main frame can be sent out one " FF " and give " virtual " keyboard, this is a reset command, and " virtual " success if keyboard resets can send one " FA AA 00 " and respond main frame.
Keyboard detection is passed through, and main frame just can enter the WINDOWS system, and to the mouse initialization, cooperates the virtual initialization mouse of main frame by described PIC16C73 virtual mouse equally, and following MOUSE refers to the mouse that PIC16C73 is virtual, and communication process is summarized as follows:
MOUSE:AA 00; AA is that self check is passed through, and 00 is mouse ID
HOST:FF; Reset command
MOUSE; FA AA 00; Mouse is replied, and self check is passed through
HOST:F3; Immediately following a byte, send the sampling rate of mouse
MOUSE:FA; Mouse is replied
HOST:C8; 200 sampled point/seconds
MOUSE:FA; Mouse is replied
HOST:F3; Immediately following a byte, send the sampling rate of mouse
MOUSE:FA; Mouse is replied
HOST:64; 100 sampled point/seconds
MOUSE:FA; Mouse is replied
HOST:F3; Immediately following a byte, send the sampling rate of mouse
MOUSE:FA; Mouse is replied
HOST:50; 80 sampled point/seconds
MOUSE:FA; Mouse is replied
HOST:F2; The fetch equipment type
MOUSE:FA 00; Reply, 00 is mouse ID
HOST:F3; Immediately following a byte, send the sampling rate of mouse
MOUSE:FA; Mouse is replied
HOST:0A; 10 sampled point/seconds
MOUSE:FA; Mouse is replied
HOST:F2; The fetch equipment type
MOUSE:FA 00; Mouse is replied
HOST:E8; Refresh the resolution of mouse immediately following a byte
MOUSE:FA; Mouse is replied
HOST:03; The 8COUNTS/ millimeter
MOUSE:FA; Mouse is replied
HOST:E6; Enable 1: 1 ratio
MOUSE:FA; Mouse is replied
HOST:F3; Immediately following a byte, send the sampling rate of mouse
MOUSE:FA; Mouse is replied
HOST:28; 40 sampled point/seconds
MOUSE:FA; Mouse is replied
HOST:F4; Enable mouse
MOUSE:FA; Mouse is replied
After the mouse initialization is finished, PIC16C73 just can deal with data, whether the keyboard mouth that at first detects host side has data, then read a byte data if any data from described keyboard mouth, after adding the keyboard identification code, whether send by serial ports, transferring detection host side mouse mouth then to has data; As not detecting data at above-mentioned keyboard mouth, begin to detect the mouse mouth whether data are arranged, then read a byte data if any data from described mouse mouth, after adding the mouse identification code, send by serial ports, whether after sending, transferring the detection serial ports to has data, whether as detecting data at the mouse mouth, then directly transferring the detection serial ports to has data; When whether the detection serial ports has data, if any data, PIC16C73 judges it is keyboard data or mouse data according to identification code, be sent to corresponding interface after determining, the keyboard mouth that is sent completely and begins to forward to main frame detects whether data are arranged, cycle detection like this, virtual PS/2 equipment is communicated by letter with main frame.In addition, in that keyboard mouth and mouse mouth do not have under the data conditions at ordinary times, serial ports always is in accepting state, also is/RE, DE is 0, and serial ports adopts interrupt mode in addition, so that PIC16C73 has more time to go to detect the variation of PS/2 mouth (comprising keyboard mouth and mouse mouth) data and clock line, concrete, after detecting data line and dragging down, then begin to prepare to receive data, the flow process that sends a byte data to main frame is described below, with reference to shown in Figure 6:
Step 601 waits for that clock line is high; Step 602 time-delay 50 microseconds; Step 603 judges that whether clock line is high, as for height enters step 604, otherwise returns step 601; Whether step 604 judgment data line is high, for height then enters step 605, abandons otherwise enter step 611, and begins to read a byte from main frame; Step 605 postpones 20 microseconds; Step 606 output start bit (0) begins to transmit data; 8 data bit of step 607 output; Step 608 output verification position; Step 609 output position of rest (1), a byte data end of transmission; Step 610 postpones 30 microseconds.
With reference to figure 7, send the individual data position and realize according to following flow process:
Step 701 setting/reseting data, the data that will send are sent into special buffer register; Step 702 postpones 20 microseconds; Step 703 drags down clock line; Step 704 postpones 40 microseconds; Step 705 discharges clock; Step 706 postpones 20 microseconds.
Please refer to shown in Figure 8ly, read a byte data from the PS/2 mouth of main frame and comprise following flow process:
Step 801 waits for that clock line is high; Step 802 is after clock line is height, and then whether the judgment data line is low, and data line is low as described, then equipment end can tranmitting data register, enters step 803 and begins to receive data, reads in 8 data bit, be that height then illustrates wrong generation further, abandon reading as detecting data line; Step 804 continues to read in check bit after reading 8 data bit; Step 805 is read in position of rest; In front, whenever reading in behind the position all, whether the test clock line is dragged down by main frame, do not drag down and just continue to read next bit, otherwise, illustrate that main frame abandons current transmission, whether step 806 judgment data line is low, if for low enter that step 810 keeps clock until data line for high, produce a mistake then, tell main frame will abandon current transmission; Step 807 output response bits tells host data to receive; Step 808 is checked check bit, produces a mistake if check bit is incorrect; Step 809 postpones 45 microseconds, so that suppress the transmission of next time for the main frame time.
With reference to shown in Figure 9, in data read process, read each data bit and carry out following flow process:
Step 901 postpones 20 microseconds; Step 902 drags down clock line; Step 903 postpones 40 microseconds; Step 904 discharges clock, produces a rising edge, prepares to read the one digit number certificate; Step 905 postpones 20 microseconds; Step 906 reading of data.
Narrate the Data Receiving/transmission processing procedure of equipment end (being the keyboard/mouse end) below, the circuit that equipment end and host side adopt is identical, power supply mode difference just, because equipment end is from the power taking of PS/2 mouth, but by externally fed.Behind the externally fed, single-chip microcomputer PIC16C73 resets, and initialization keyboard and mouse begin the cycle detection data then: whether have data, have and then read this data if detecting the keyboard mouth, adds an identification code (can be defined as 00) back and send by serial ports; Whether have data, detected data as the mouse mouth if then not beginning to detect the mouse mouth, then read this data, adds an identification code (can be defined as 01) back and send by serial ports; Whether as not detecting data at the mouse mouth, then detecting serial ports has data, has then these data to be mail to corresponding PS/2 mouth.
Here,, when handling one of them, need another data line is dragged down, suppress its communication because single-chip microcomputer PIC16C73 while dummy keyboard and mouse have conflict in order to prevent the two.
Please referring to Figure 10, the simple description write the flow process of a byte to equipment end:
Step s101 drags down at least 100 microseconds to clock line; Step s102 drags down data line; Step s103 discharges clock line; Step s104 waiting facilities drags down clock line; Step s105 setting/reseting data line sends first data bit; Step s106 waiting facilities is drawn high clock line; Step s107 waiting facilities drags down clock line; Step s908 repeating step s105-s107 sends remaining 7 data bit and a check bit; Step s109 discharges data line; Step s110 waiting facilities drags down data line; Step s111 waiting facilities drags down clock line; Step s112 waiting facilities discharges data line and clock line.
Please referring to Figure 11, for after low, begin reading of data at the data line that detects keyboard and mouse, the slave unit end reads a byte and comprises following flow process:
Step 110 is read in a start bit (0); Step 111 reads 8 data bit successively; Step 112 is read in check bit; Step 113 is read in position of rest.
Please refer to shown in Figure 12ly, read each data bit according to following flow process:
Whether step s1 detects clock line is high, for height then enters step s2, otherwise continues to detect; Step s2 detects whether clock line is low, as is low, and promptly clock has negative edge, enters step s3, otherwise continues to detect; Step s3 detects the data line state, reads in one; Step s4 returns.
Above-mentioned is that preferred embodiment is described the communication process between virtual PS/2 equipment and main frame with mouse and keyboard only; will be understood that the foregoing description does not constitute the qualification to protection domain of the present invention; in fact the present invention can also be applicable to other PS/2 equipment; any any modification of being done within the spirit and principles in the present invention, be equal to and replace and improvement etc., all should be included within the claim protection domain of the present invention.

Claims (10)

1, the method for a kind of virtual PS/2 equipment and inter-host communication is characterized in that, comprises 1) step and 2 of PS/2 equipment end fictitious host computer and PS/2 devices communicating) step of the virtual PS/2 equipment of host side and main-machine communication, described step 1) comprises:
11) PS/2 equipment is connected with first microprocessor, described first microprocessor is virtual to be main frame and the mutual PS/2 device initialize of PS/2 equipment signal, and the described PS/2 equipment of initialization;
Whether 12) described first microprocessor is virtual has the PS/2 protocol signal for main frame detects the PS/2 equipment end, if any then carrying out respective handling, otherwise continues to detect;
Described step 2) comprising:
21) main frame is connected with second microprocessor, described second microprocessor is virtual to be PS/2 equipment and the mutual PS/2 device initialize of main frame signal, and by the virtual initialization PS/2 of described main frame equipment;
Whether 22) described second microprocessor is virtual has the PS/2 protocol signal for PS/2 Equipment Inspection host side, if any then carrying out respective handling, otherwise continues to detect.
2, according to the method for described virtual PS/2 equipment of claim 1 and inter-host communication, it is characterized in that, adopt the communication of RS485 protocol mode between described first microprocessor and described second microprocessor.
3, according to the method for described virtual PS/2 equipment of claim 2 and inter-host communication, it is characterized in that described PS/2 equipment is keyboard and/or mouse.
4, according to the method for described virtual PS/2 equipment of claim 3 and inter-host communication, it is characterized in that described step 12) further comprises:
Whether a1) described first microprocessor is virtual has data for main frame detects the keyboard mouth, if any then reading a byte data from the keyboard mouth, and sends by serial ports, enters step a2 then), as not detecting data, then directly enter step a2);
Whether have data, as detect the mouse mouth data are arranged if a2) detecting the mouse mouth, then read a byte data from the mouse mouth, and send by serial ports, enters step a3 then), as not detecting data, then directly enter step a3);
Whether have data, as detect serial ports data are arranged if a3) detecting serial ports, then described data are sent to the corresponding interface, goes back to step a1) continue to detect, then directly get back to a1 as not detecting data) continue to detect;
Described step 22) further comprise:
Whether b1) described second microprocessor is virtual has data for the keyboard mouth of the described main frame of PS/2 Equipment Inspection, read a byte data if any keyboard mouth then from described main frame, send by serial ports, enter step b2 then), then directly enter step b2 as not detecting data);
B2) whether the mouse mouth that detects described main frame has data, reads a byte data if any the mouse mouth from described main frame then, sends by serial ports, enters step b3 then), then directly enter step b3 as not detecting data);
Whether have data, as detect serial ports data are arranged if b3) detecting serial ports, then described data are sent to the corresponding interface, goes back to step b1) continue to detect data, then directly get back to b1 as not detecting data) continue to detect.
5, according to the method for described virtual PS/2 equipment of claim 4 and inter-host communication, it is characterized in that, described step a3) also comprises the step of judgement: judge that by the identification code of data the data that receive at serial ports are host keyboard mouth data or main frame mouse mouth data, identification code is the identification code of sign host keyboard mouth data as described, then described data are sent to the keyboard mouth, identification code is the identification code of sign mouse mouth data as described, then described data is sent to the mouse mouth;
Described step b3) also comprises the step of judgement: judge that by identification code of date the data that receive at serial ports are keyboard mouth data or mouse mouth data, identification code is the identification code of marking keyboard mouth data as described, then described data are sent to the host keyboard mouth, identification code is the identification code of sign mouse mouth data as described, then described data is sent to main frame mouse mouth.
6, according to each the described virtual PS/2 equipment of claim 1-5 and the method for inter-host communication, it is characterized in that described microprocessor is single-chip microcomputer PIC16C73.
7, the device of a kind of virtual PS/2 equipment and inter-host communication comprises PS/2 equipment and main frame, it is characterized in that, also comprises in the PS/2 equipment end:
First microprocessor, its I/O mouth links to each other with the PS/2 protocol interface of PS/2 equipment, is used for the initializing signal of fictitious host computer and the mutual PS/2 equipment of PS/2 equipment, and the PS/2 protocol signal of the described PS/2 equipment of initialization and detection and processing PS/2 equipment end;
Also comprise in host side:
Second microprocessor, link to each other with first microprocessor, its I/O mouth links to each other with main frame PS/2 protocol interface, is used for the initializing signal of virtual PS/2 equipment and the mutual PS/2 equipment of main frame, and by the PS/2 protocol signal of main frame virtual initialization PS/2 equipment and detection and processing host end.
8, according to the device of described virtual PS/2 equipment of claim 7 and inter-host communication, it is characterized in that, described PS/2 equipment end also comprises a RS485 circuit, a described RS485 circuit is connected with first microprocessor serial ports I/O pin by transmissions/receiving port, is used for that the asynchronous serial signal that first microprocessor is exported is carried out corresponding difference processing and sends to main frame then or the differential signal that main frame is brought in is reduced processing and send to first microprocessor.
Described host side also comprises the 2nd RS485 circuit, link to each other with a RS485 circuit, and be connected with the second microprocessor serial ports I/O pin by transmissions/receiving port, be used for that the asynchronous serial signal that second microprocessor is exported is carried out corresponding difference processing and send to PS/2 equipment then or the differential signal that PS/2 equipment is brought in is reduced processing and send to second microprocessor.
9, according to the device of claim 7 or 8 described virtual PS/2 equipment and inter-host communication, it is characterized in that described PS/2 equipment is keyboard and/or mouse.
10, according to the device of described virtual PS/2 equipment of claim 9 and inter-host communication, it is characterized in that, the described first microprocessor and second microprocessor are single-chip microcomputer PIC16C73 chip, and a described RS485 circuit and the 2nd RS485 circuit are the MAX3486 chip;
4 I/O mouth RA0~RA3 of described single-chip microcomputer PIC16C73 chip as first microprocessor link to each other with the PS/2 protocol interface of keyboard and mouse respectively so that the mutual PS/2 protocol signal of fictitious host computer and keyboard or mouse, asynchronous serial port transmission/reception pin RC6/RC7 links to each other with reception/transmission pin R0/D1 as the MAX3486 chip of a RS485 circuit so that the signal of keyboard/mouse is converted into the output of asynchronous serial signal or receives asynchronous serial signal through the reduction of MAX3486 difference, and control signal I/O pin RC4~RC5 links to each other so that control the transmission/accepting state of MAX3486 chip with control signal pin/RE~DE as the MAX3486 chip of a RS485 circuit;
4 I/O mouth RA0~RA3 of described single-chip microcomputer PIC16C73 chip as second microprocessor link to each other so that the mutual PS/2 protocol signal of dummy keyboard or mouse and main frame with the keyboard of main frame mainboard and the PS/2 protocol interface of mouse respectively, link to each other with reception/transmitting terminal as the MAX3486 chip of the 2nd RS485 circuit signal with host keyboard mouth/mouse mouth of asynchronous serial port transmission/reception pin is converted into the output of asynchronous serial signal or receives asynchronous serial signal through the reduction of MAX3486 difference, and control signal I/O pin RC4~RC5 links to each other so that control the transmission/accepting state of MAX3486 chip with control signal pin/RE~DE as the MAX3486 chip of a RS485 circuit;
Link to each other with netting twine or CAT5E UTP cable between the described MAX3486 chip.
CNB2004100307020A 2004-03-31 2004-03-31 Method and device for two-way communication between virtual PS/2 apparatus and host machine Expired - Fee Related CN100346271C (en)

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