RU2037212C1 - Indicating apparatus - Google Patents

Abstract

FIELD: automatics and computing technique, systems for collecting and storing information. SUBSTANCE: apparatus has the clock pulse generator 4, the synchronization unit 5, the pulse shaper 6, the code converter 3, the switching unit 2, the unit 7 for detecting errors, the indicating device. EFFECT: enlarged using range. 2 cl, 2 dwg 1 tbl

Description

 The invention relates to automation and can be used in information display devices.

 A device is known for monitoring sign-synthesizing indicators on LEDs, which contains a series-connected code converter, a key block and a block of current-setting resistors, the outputs of which are connected to the indicator inputs and to the inputs of the “I” element and providing a fault signal in the presence of an LED break in the indicator board (1) .

 A disadvantage of the known device is limited functionality, since the device does not allow to detect a malfunction of the LEDs of the controlled group, if these LEDs are excited in a dynamic mode, i.e., at the same time, it does not allow to identify a specific LED in the group of simultaneously controlled LEDs with an open circuit, does not allow to identify the malfunction of the display panel "circuit addressing buses."

 Indeed, the health assessment is carried out at the time of monitoring using the AND element according to the coincidence of the signal levels supplied to the indicator elements.

 If the LEDs are excited at various points in time, then a health signal will not be generated.

 Since all the input signals of the And element are equivalent and the output signal of the And element does not carry information about a specific faulty circuit, but gives an assessment of the health of a group of simultaneously checked LEDs, a specific faulty element is not detected by hardware.

 Further, when the LED electrodes are closed, the current flowing through the block of keys and the block of current-setting resistors is preserved, therefore, using the AND element, a malfunction of this kind is not detected.

 A device for indicating is known that contains series-connected information sources, control units and indicator elements, series-connected malfunction detection unit and driver of control signals, series-connected pulse generator and OR element, the second output of which is connected to the first output of the driver of control signals, and the output is connected to the blanking control input of the control unit and providing periodic self-monitoring of the health of indicator elements with a period ohm specify the pulse generator with the transition automatically display mode if the fault is detected and a transition into the diagnostic mode when a fault is detected, then the display of information is locked, all the elements illuminates boards that allows visual lekalizovat defective display element (2).

 The functionality of this device is also insufficient for reliable monitoring of the status of the indicator board, as the health (or malfunction) of the display elements is assessed by the malfunction detection unit, which is an AND element with an output signal exposure. The use of the And element as the main unit of the malfunction detection unit determines the same disadvantages of the device as the device (1) the impossibility of element-wise control, the inability to detect the short circuits of the LED electrodes.

 However, the device (2) is the closest in technical essence to the proposed device, which also implements self-control of the indicator board elements during a special control cycle, periodically repeated at a low frequency and not affecting the perception of the displayed information, and the possibility of visualizing the faulty element during exposure is realized all elements of the indicator board in the "control" mode, when the display of information is blocked. Therefore, the device (2) is taken as a prototype of the invention. For convenience, the description of the invention, it is advisable to somewhat transform the structural diagram of the device (2), while maintaining equivalence.

 The set of display elements is presented in the form of an indicator board. The pulse generator is represented by an equivalent pulse shaper of the monitoring time interval. The set of series-connected clock generator, synchronization unit and code converter of the proposed device is the equivalent of the set of device information sources (2), and the set of control units is equivalent to the current switch.

 The aim of the invention is to increase the reliability of monitoring the state of the sign-synthesizing indicator.

 This goal is achieved by the fact that in a device containing a series-connected clock generator and a synchronization unit, a series-connected current switch and an indicator board, a series-connected pulse shaper and a fault detection unit, the output of which is the device output, a code converter, the outputs of which are connected to the corresponding inputs current switch, the inputs of the first group of inputs of the code converter are the information inputs of the device, and the first, second and third the inputs of the second group are connected respectively to the first, second and third outputs of the synchronization block, additional connections of the fourth, fifth and sixth outputs of the synchronization block, respectively, are introduced with the first; the second and third inputs of the third group of inputs of the code converter, the first control input of which is connected to the control input of the device, the second control input is connected to the output of the pulse shaper, the first and second inputs of which are connected respectively to the seventh and eighth outputs of the synchronization unit, while the current switch power bus connected to the power bus of the device, the common bus of the current switch is connected to the second input of the fault detection unit, the second output of which is connected to the zero potential bus Ala.

 The fault detection unit contains the first and second comparators, the inputs of which are connected to the input of the unit and are connected through the resistor to the zero potential bus, the elements NOT connected in series, the AND element and the OR element, the second input of which is the control input of the unit, the output of the first comparator is connected to the second input AND element, the output of the second comparator is connected to the input of the element NOT, and the output of the OR element is the output of the block.

 The essence of the present invention lies in the fact that in the display device containing an indicator board and the current switch necessary for controlling this board, a code converter, a synchronization unit and a clock generator, as well as an impulse generator for the monitoring time interval necessary for organizing self-monitoring, means for assessing health are introduced the indicator elements checked during self-control and the formation of a signal of serviceability (or malfunction) of the indicator board, means of blocking from reflects the time information to the self-monitoring and flow instead of special test signals and the illumination of all of the indicator board in "control" mode, the signal means when the defective elements observed visually.

 In FIG. 1 shows a structural diagram of the proposed device; in FIG. 2 is a block diagram of a fault detection unit.

 The proposed device contains (Fig. 1) an indicator board 1, a current switch 2, a converter 3 of the displayed information code to an indicator control code, a clock pulse generator 4, a synchronization unit 5, a pulse control time generator 6 of the indicator board, an indicator board malfunction detection unit 7, inputs 8 of the displayed information code, input 9 of the control signal for selecting the "control" mode, bus 10 of the current switch power supply, common bus 11 of the current switch, bus 12 of zero potential, output 13 of the fault signal tab oh, the clock signal transmission line 14 of the clock generators, the scan synchronization signal transmission line 15, the scan clock code transmission line 16, the control code transmission line 17, the control signal generation signal transmission line 18, the pulse former output communication line 19 with the control input of the code converter and with a control input of the fault detection unit, a current commutator control signal transmission line 20, an indicator board addressing line 21.

 The fault detection unit contains (Fig. 2) a resistor 22, voltage comparators 23 and 24, an element 25 NOT, an element 26 AND, an element 27 OR.

 The device operates as follows.

 Addressing the elements of the indicator board 1 is carried out by the current switch 2, providing the necessary currents to the addressing bus 21.

 Scanning is provided in N cycles. Management of the switch 2 is provided by the converter 3 of the information code into the indicator control code. For a scan cycle at the output of the converter 3, N code combinations are formed sequentially, each of which corresponds to a group of simultaneously illuminated indicator elements that make up a fragment of the symbol being depicted. The synchronization of the information code conversion process is provided by the synchronization unit 5, the input of which is transmitted through the communication line 14 by a clock signal of a 4-clock generator.

 On the positive edge of the clock signal in block 5, a scan synchronization pulse is generated and by dividing the clock frequency a scan control code is generated. The synchronization signal is supplied to the code converter 3 on the communication line 15, and the signal of the sweep control code is on the line 16. When the indicator board 1 is scanned for eight clock cycles (N 8), the sweep control code is three-digit and is generated by dividing the clock frequency by 2, 4 and 8.

, (где f_r частота тактов развертки, f_p частота развертки, N количество тактов развертки) обеспечивает регенерацию изображения на индикаторном табло.The code of the displayed information is fed to the inputs 8 of the code converter 3. For each code combination at input 8. At the output of the converter 3, a sequence of successive code combinations forming a sweep cycle is formed. Periodic repetition of sweep cycles with a frequency f _r

, (where f _{r is the} frequency of the clock cycles, f _{p is the} frequency of the scan, N is the number of clock cycles) provides regeneration of the image on the indicator board.

 The code conversion mode of the information received at input 8 is the main mode of operation of the converter 3, since the information display mode is the main mode of operation of the proposed device.

 To enable visual monitoring of the health of the indicator board in the proposed device provides such a mode of operation of the Converter 3, when at its outputs a sequence of code combinations is formed, providing illumination for the scan cycle of all elements of the indicator board.

 The signal for selecting the "control" mode is fed to the input 9 of the device, while the conversion of the input information code is blocked.

The total current switched by the switch 2 from the power source (bus 10) in the process of sweeping the indicator board depends on the number of simultaneously included elements of the board. If the indicator board is made on the same type of elements with the same nominal excitation current I _nom , and during the sweep the indicator elements are illuminated one at a time, then a current equal to the nominal I _nom flows through the switch 2 during the sweep. In this case, any deviation of the current value from the nominal limits is evidence of a malfunction of the indicator board. The operation of the malfunction determination unit 7 is based on this principle (FIG. 2). The structure of block 7 includes a resistor 22 connected between the common bus 11 of the switch 2 and the common bus of the device (bus 12 of zero potential). Resistor 22 is a current sensor. The voltage drop across the resistor 22 is supplied simultaneously to two voltage comparators 23 and 24. Both comparators are made according to the same scheme, however, they differ in the response threshold. The threshold of the comparator 23 is set by the level of the minimum current I _min , and sometimes the comparator 24 by the level of the maximum current I _max , where I _min and I _{max the} boundaries of the spread of current values of a working indicator element, i.e.

I _min <I _nom <I _max
The comparator is triggered when the voltage drop across the resistor 22 when the current of the switch 2 flows through it exceeds the threshold level of the comparator, while a log signal is generated at the output of the comparator. 1.

Consider the possible state of the comparators:
a) at a current through the resistor 22 I <I _min ,
the signal at the output of the comparator 23 a 0,
signal at the output of the comparator 24 b 0;
b) at a current through the resistor I _min <I <I _max (i.e., within the tolerance), the signals a 1, b 0 are generated at the outputs of the comparators;
c) at current I> I _{max the} signal at the outputs of the comparators a 1 and b 1;
d) the signals a 0 and simultaneously b 1 are possible only if the comparators malfunction.

 In the process of scanning, for an arbitrary number of excited elements, indicating the status of the comparators do not carry information about the malfunction or malfunction of the indicator board. To obtain information on serviceability, it is necessary to organize the excitation of indicator elements one at a time during a special periodically repeating cycle of self-monitoring. The malfunction signal of the indicator board should be formed only at the moments of excitation of the indicator elements during the self-monitoring cycle.

To this end, the output signals of the comparators 23 and 24 are fed to a combinational circuit containing an element 25 NOT, an element 26 AND and an element 27 OR and implementing a logical function,
where a is the output signal of the comparator 23,
b output signal of the comparator 24,
with the output signal of the shaper 6 of the pulse of the time interval of self-control.

In this case, C 0 during the time interval of the self-monitoring cycle T _o , c 1 during the time interval of the cycle of indication T _n

The duty cycle of the proposed device T _slave thus consists of a display cycle T _n and a cycle of self-control T _s .

= МТ_т
Работа блока 7 определения неисправности полностью описывается в таблице истинности.T _slave T _and + T _s
The duration of the self-control cycle is determined by the clock frequency f _t and the number of elements of the indicator board M, which must be checked
T _s ≥ M

= MT _t
The operation of the malfunction determination unit 7 is fully described in the truth table.

The start of the pulse shaper 6 of the time interval of self-monitoring is carried out by signals arriving on line 18 from the outputs of the cascades for dividing the clock frequency into 2 ⁷ and 2 ¹⁵ of synchronization unit 5. At a clock frequency f _{t, the} frequencies of the input signals of the shaper 6 are respectively f _t 2 ^-7 and f _t 2 ^-15 , i.e., self-monitoring is performed over a 64 clock cycle and is periodically repeated after 4096 scan cycles (T _with 2 ¹² T _p ; T _p 8T _t ).

During the time interval of self-control by a low potential level pulse from the output of the shaper 6, which is sent through line 19 to the second control input of the code converter 3, the input information code is blocked and a sequence of code combinations is generated at the output of the converter 3, each of which sets the switch 2 to the mode addressing one display element, while the input code of the converter 3 is created by signals from the outputs of block 5 from the cascades of frequency division by 2.2 ² , 2 ³ ; arriving on the communication line 16 and from cascades of dividing the clock frequency by 2 ⁴ , 2 ⁵ , 2 ⁶ , arriving on the communication line 17.

 This six-digit input code of the converter 3 allows you to check up to 64 indicator elements during the self-monitoring cycle. At the end of the self-control cycle by the control signal via the communication line 19, the code converter 3 is automatically transferred to the input information code conversion mode.

 In the "control" mode, when the indicator board lights up completely, the operating cycle of the device remains the same, that is, it contains an indication cycle and a self-control cycle.

Since the duration of the self-monitoring cycle is much shorter than the duration of the indication cycle T _s << T _and , where T _s 2 ⁶ T _t , T _and 2 ¹⁵ T _t -T _s , i.e. T _s 2-10 ^-3 T _and , deterioration indication quality is practically not observed; since on the one hand there is no decrease in the brightness of the display due to a pause for self-control, and on the other hand there is no interfering illumination of the indicator board.

 Thus, the proposed device implements not only the ability to display information from external devices, not only provides the ability to visually control the indicator board by the operator’s command, but also implements automatic control of the health of the indicator board without affecting the perception of the displayed information, and a signal about there is a malfunction in the indicator board.

Claims (2)

 1. DEVICE FOR INDICATION, comprising a switch, the group outputs of which are connected to the indicator inputs, a fault detection unit, the information input of which is connected to the switch output, a pulse shaper, a clock pulse generator, characterized in that, in order to increase the reliability of the device, it comprises a converter code and synchronization unit, the clock input of which is connected to the output of the clock generator, and the first output is connected to the clock input of the code converter, the outputs of the group of the sync block they are connected to the control inputs of the code converter group, the outputs of which are connected to the control inputs of the switch, the information and control inputs of the code converter are respectively the information and control inputs of the device, the control input of the code converter is connected to the control input of the fault detection unit and to the output of the pulse shaper, the first and the second control inputs of which are connected respectively to the second and third outputs of the synchronization block, the output of the block aruzheniya fault is an output device.  2. The device according to claim 1, characterized in that the fault detection unit contains two comparators, an element NOT, an AND element, an OR element, and a load element on a resistor, one terminal of which is connected to the zero potential bus, and the other with the first inputs of the comparators the information input of the unit, the outputs of the first and second comparators are connected respectively to the first input of the AND element and the input of the element NOT, the output of which is connected to the second input of the AND element, the output of which is connected to the first input of the OR element, the second input to stroke which are respectively input and output control unit.

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