CN2157545Y

CN2157545Y - Tester for computer monitoring system

Info

Publication number: CN2157545Y
Application number: CN 93216847
Authority: CN
Inventors: 张冶
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-06-24
Filing date: 1993-06-24
Publication date: 1994-02-23
Anticipated expiration: 2003-06-24

Abstract

The utility model relates to standard equipment for carrying out checks to a computer monitoring system in order to replace the original various kinds of single-function equipment for tests. The utility model is intelligent equipment using a single-chip microcomputer as a core, and comprises an analog quantity output circuit and a switching quantity output circuit, wherein, standard output signals of the analog quantity output circuit can be converted into constant current sources, or constant voltage sources, or analog resistances; the switching quantity output circuit can do the tests of switching quantity and pulsed quantity. The utility model has the advantages of flexible operation, convenient test and high precision, and provides integrative standard equipment for doing the check tests to the computer monitor system by laboratories, measuring rooms, and fields.

Description

Tester for computer monitoring system

The utility model relates to a kind ofly to be tested or the standard device of verification computer monitor system, belongs to the metering outfit technical field that comprises multiple physical quantity test or calibration.

Computer monitor system is a kind of emerging technology, it is core with the computing machine, send device to deliver in the computing machine by corresponding change various analog quantitys, switching value, the pulsed quantity of industry spot collection, finish Signal Processing, and on monitor, show related parameter or pattern, also can realize parameter control.Yet with regard to computer monitor system self, should accomplish that parameter shows accurately, the switching value order is correct, and simulation figure is clear, during to the Installation and Debugging of system and maintenance, all should have corresponding standard equipment to come checksum test.Traditional method of calibration is that different variablees is adopted different instruments, for example uses potential difference meter, and standard signal generator, standard voltmeter and standard resistance box wait the various analog quantitys of verification, advance frequency meter with square-wave generator and ten and come the verification pulsed quantity.Also be provided with homemade specialized equipment at present as for the verification switching value, import equipment " computer logic tester " costs an arm and a leg though can carry out this test.Many stand arrangement are united use, complex operation, and precision is difficult for coupling, makes mistakes easily, carries inconvenience simultaneously, is not suitable for the on-the-spot needs that use.

The purpose of this utility model is for computer monitor system provides a kind of integrated integration test calibration equipment, can carry out the verification of computer monitor system analog quantity commonly used and switching value easily.

Task of the present utility model is achieved in that one is that core comprises in the appliance computer device of random memory, read-only memory, latch, code translator and keyboard, printing, display unit with the single-chip microcomputer, also is provided with an analogue quantity output circuit and a switching value output circuit.Described analogue quantity output circuit is by digital to analog converter, the canonical reference potential circuit, the direct current proportional amplifier, multicircuit switch and output transform circuit are formed, the digital to analog converter output terminal is electrically connected with multicircuit switch through the direct current proportional amplifier, each output terminal of multicircuit switch is connected with each output transform circuit respectively, and described output transform circuit comprises constant voltage power supply circuit at least, constant-current source circuit and artifical resistance.Described switching value output circuit is provided with an I/D expansion board, and the bi-directional data mouth of this expansion board is connected with described computer data bus, and its parallel delivery outlet is exported through photoelectrical coupler respectively.

Can determine test-types and parameter with keyboard input or set-up mode after adopting such scheme, promptly at first selecting is analog quantity or switching value, but selecting under the analog quantity verification situation also choice criteria millivolt signal, normal voltage signal, current signal commonly used and artifical resistance output, respectively to the thermopair test section of computer monitor system, the voltage signal part, transmitter part and thermal resistance part of detecting carry out verification; Under selector switch amount verification situation, the 24 way switch amounts of verification simultaneously provide " with verification at interval " and " changing distance verification " dual mode.Can finish test and verification with a table apparatus like this to the multiple performance of computer monitor system, can improve the accuracy rate of surveillance greatly, the correctness of switching value journal and pulsed quantity counting, the various test volume Accuracy Matching that provided, flexible operation, convenient reading, volume is little, in light weight, compact conformation also is easy to carry.

With regard to drawings and Examples the utility model is specified below.

Fig. 1 is the device front view.

Fig. 2 is a circuit block diagram.

Fig. 3 is analog quantity output circuit theory diagrams.

Fig. 4 is switching value output circuit theory diagrams.

Device panel 1 is provided with digital display tube 2 among Fig. 1, but read clock, channel number and spacing value, output prompt etc.Also be provided with printer outlet 3, printer observation panel 4 analog quantity test event switch keys 5, numeric keypad and adjustment key 6, switching value feeler switch 7 and switching value output indicator 8.Power switch, supply socket and terminal aviation plug are located on the back plate of device.

Fig. 2 is the principle of device block diagram, comprise single-chip microcomputer 8031, EPROM27128, RAM6264, code translator 11, latch 12, printer μ p-40, keyboard 13, show 14 and show the appliance computer essential part of the composition such as I/D expansion board 8255 grades that is connected, also be provided with the switching value output circuit that an analogue quantity output circuit of being made up of analog to digital converter 18 and multi-way switch 17 and expansion board 8255 and isolator 15 are formed with keyboard.Described analog to digital converter 18 is connected with data bus DB, and a canonical reference voltage generator 16 provides V for data converter 18 _RefThe two-way I/O mouth P0 of single-chip microcomputer 8031, P1 is connected with data line DB and address wire AB respectively with P2.Latch 12 is by 8031 ALE pin gating, and EPROM is by 8031 PSEN pin gating, and digital to analog converter 18 is by code translator 11 gatings.Under the analog quantity way of output, 8031 single-chip microcomputers are provided with binary signal of output according to keyboard and convert analog quantity to by digital to analog converter 18, with canonical reference voltage V _ReF is a standard control of back output voltage relatively, as constant voltage power supply circuit 21,22, and the input signal of constant-current source circuit 19 or simulative resistance circuit 20.Under the switching value verification mode, 8031 single-chip microcomputers by sequential operation, are pressed pulse that given interval set through switching value output expansion board 8255 and optocoupler isolator 15 outputs according to the keyboard setting, and the current potential of signal also can be adjusted.Printer μ p-40 can print respective settings value and verification amount simultaneously.

D1, R4 form the voltage stabilizing network of amplifier G1 input voltage+U among Fig. 3, make the output voltage U of the direct current ratio amplifying circuit of this amplifier G1 composition by the adjustment of input resistance R3 and feedback resistance R2, R1 _REFBe stabilized in very on the accurate values, give analog to digital converter DAC0832V _RefEnd the canonical reference voltage signal is provided.Use resolution and the precision of two eight analog to digital converter DAC0832 in the present embodiment to guarantee output signal.Amplifier G2 end of oppisite phase resistance is composed in series by R5 and R6, and the Iout of first DAC0832 directly connects the end of oppisite phase of G2, and the Iout of second DAC0832 is connected with the link of resistance R 5, R6.The Vref of two DAC0832 holds and connects the output terminal of amplifier G1, but amplifier G2 feedback line only is connected with the Rfb end of first DAC0832.From the normal voltage signal input mux CD4057 of amplifier G2 output, its control end A0, A1 obtain two control words from PC6, the PC7 of expansion board 8255, select a mouth output among Y0, Y1, Y2 or the Y3.Wherein Y0 is connected with the constant voltage power supply circuit that an amplifier G3 forms with Y1, and output second gear normal voltage signal is done the verification of 0-100mV millivolt for one grade, and another shelves are done the verification of 0-10V normal voltage.The accuracy of this second gear parameter can reach 0.15% and 0.01% respectively, and resolution can reach 1 μ V and 1mV respectively.Y2 is connected with the constant-current source circuit that triode is formed with amplifier G4 and field effect transistor, and the outputting standard current signal is done the verification of 0-20mA electric current, and its accuracy can reach 0.1%, and resolution is 1 μ A.Y3 then is connected with integrated circuit 5517A, and the standard control signal is converted to artifical resistance, and the verification of 0-200 Ω resistance is provided, and accuracy reaches 0.01%, and resolution can reach 0.01 Ω.

Fig. 4 is the switching value output circuit.The bi-directional data mouth D0-D7 that is used for the expansion board 8255 of this circuit is connected with data bus DB, and three groups of parallel port PA, PB and PC can export 24 switching value D1-D24 simultaneously after 24 photoelectricity coupling device TIL113 isolate.The current potential of output switching value can be adjusted to 24V, 12V, 6V number grade, and output waveform can be rising edge, negative edge or rectangular wave, also can select " with verification at interval " and " changing distance verification ".Under strobe pulse amount verification mode, certain a bite of 8255, for example the PC mouth is exported the pulsed quantity of certain intervals, and the pulse width of pulsed quantity and cycle can be through keyboard to set up.

Program Solidification is in EPROM, and when the guidance panel switch, after test of selection analog quantity or the switching value test, programmed control hardware enters specified states.Selecting under the analog quantity output situation, program inquiry output parameter form, and to multicircuit switch transmission control word.Under selector switch amount output situation, program continues the inquiry keyboard with acquisition each setting value relevant with switching value or pulsed quantity.Show and printing etc. also all carries out under programmed control.

Claims

1, a kind of computer monitor system proving installation, it is characterized in that described device is one and comprises single-chip microcomputer at least, memory, latch, code translator, the Computer Control Unit of keyboard and display, also be provided with an analogue quantity output circuit and a switching value output circuit, described analogue quantity output circuit is by digital to analog converter, the canonical reference potential circuit, the direct current proportional amplifier, multicircuit switch device and output transform circuit are formed, the digital to analog converter output terminal is connected with the output transform circuit with multicircuit switch through the direct current proportional amplifier, described switching value output circuit is provided with an I/D expansion board, its bi-directional data mouth is connected with data bus, and its parallel delivery outlet is respectively through photoelectrical coupler output switching value.

2, by the described computer monitor system proving installation of claim 1, it is characterized in that described digital to analog converter is formed by two serial connections, the end of oppisite phase of first digital to analog converter output termination amplifier G2, two resistance in series R5 of the output termination G2 inverting input of second digital to analog converter and the series side of R6, the output terminal feedback line of this amplifier G2 connect first digital to analog converter Rfb end.

3, by claim 1 or 2 described computer monitor system proving installations, it is characterized in that described analog quantity output transform circuit comprises constant voltage power supply circuit, constant-current source circuit and simulative resistance circuit.