US3818474A

US3818474A - Method of and apparatus for comparing desired and actual values presented in digital form

Info

Publication number: US3818474A
Application number: US00121841A
Authority: US
Inventors: H Kurner; K Bindewald; M Schwarztrauber; L Eckmar
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 1970-03-10
Filing date: 1971-03-08
Publication date: 1974-06-18
Anticipated expiration: 1991-06-18
Also published as: FR2081817A6; GB1349792A; DE2011194C3; NL7102898A; IT984531B; DE2011194B2; DE2011194A1

Abstract

Digitally represented desired and actual value series are plotted in graph form on a television screen for the purpose of comparison. The corresponding desired and actual values are shown in the same line of the picture so that the desired value curve and the actual value curve extend parallel to one another. In order to be able to predict the future course of the actual value curve, the desired value curve runs across the entire screen, while the actual value curve extends only across a part thereof. The most recent actual values are shown in a midportion of the screen. In this manner, desired values are shown for which no corresponding actual values are yet available.

Description

Kurner et al.

United States Patent 91 METHOD OF AND APPARATUS FOR COMPARING DESIRED AND ACTUAL VALUES PRESENTED IN DIGITAL FORM Assignee:

Filed: Mar. 8, 1971 Appl. No.: 121,841

Siemens Aktiengesellschaft, Berlin and Munich, Germany Foreign Application Priority Data Mar. 10, 1970 Germany Int. Cl.

Field of Search 340/324 A, 324 AD;

References Cited UNlTED STATES PATENTS ACTUAL VALUE MEMURY REAUUUT REGISTER 1 June 18, 1974 3,406,387 10/1968 Wcrme 340/324 A 3,474,438 10/1969 3,487,308 12/1969 3,518,657 6/1970 3,522,597 8/1970 Murphy 340/324 A Primary Examiner.1ohn W. Caldwell Assistant Examiner-Marshall M. Curtis Attorney, Agent, or Firm-Edwin E. Greigg [5 7] ABSTRACT Digitally represented desired and actual value series are plotted in graph form on a television screen for the purpose of comparison. The corresponding desired and actual values are shown in the same line of the picture so that the desired value curve and the actual value curve extend parallel to one another. In order to be able to predict the future course of the actual value curve, the desired value curve runs across the entire screen, while the actual value curve extends only across a part thereof. The most recent actual values are shown in a midportion of the screen. In this manner, desired values are shown for which no corresponding actual values are yet available.

7 Claims, 8 Drawing Figures 1 PROCESS CALCULATOR MEMURV L: 7 I DESIRED VALUE MEMURV Inl Inf il, L

cFRFARAmR I -mmmzmn cmcun arm GENERATOR j IL 5 2 smuu V SCALE-DOWN 5 EENTRAL cmcun Vl UEU APPARATUS PATENTED 81974 3,818,474

sum .1 OF 4 3 PROCESS CALCULATOR MEMORY Inf Inf I r ACTUAL N DESIRED VALUE MEMORY

VALUE MEMORY

21 ,22 ,17 READUUT 1 REAUUUT ADDRESS REGISTER REGISTER BUUNTER COMPARATOR cmcun /CUMPARATUR CIRCUIT '23 21.

BEAT(GENERATUR 2U-CUUNTER .11 "5 2 SIGNAL smwnnwu 5 CENTRAL H CIRCUIT 7 -EEB Fi .1 VIDEO 9 APPARATUS INSERIBINB R lsTER REAUUUTR EE2\\ EB mscmsms AND READUUT REBISTER\\ L2 9 r 8%: 1 r I l 1.1 10

s SHIFT REGISTER sm REGISTER -L.

DESIRED VALUE MEMORY ACTUAL VALUE MEMURY Fig. '2

E 1. 15 19 r K SHIFT CUUNTER DESIRED INSDRIPTIUN l VALUE MEMORY EUNTRUL ATUR cmcun 5 ADDRESS CUUNTER ACTUAL E VALUE MEMORY Fig.3

PAIEIIIED I 81974 SHEET 3 0F 4 SHIFT COUNTER I i B(K T CUMPARATUR\ I I I HATE CIRCUIT i URCUH 1 ADDRESS 7 I TR|55ER COUNTER VIM I PAIR cmcun 25 I COMPARATOR CIRCUIT I SH FT //27 I E I u COUNTER I mm INFZ DESIRED ACTUAL LINE COUNTER VALUEMEMURV VALUE MEMORY u mg M001 M002 CIRCUIT UEBI UEBZ 17 \AUURESS 31 I l CUUNTER COMPARATOR '|B\ r CIRCUIT FUNCTION msnmpnuu REGISTER CUNTRUL I v CIRCUIT 19 SHIFT f CUUNTER in 15 Fig.5

METHOD OF AND APPARATUS FOR COMPARING DESIRED AND ACTUAL VALUES PRESENTED IN DIGITAL FORM BACKGROUND OF THE INVENTION This invention relates to a method of and apparatus for comparing actual and desired values presented in digital form.

The usual way to proceed in the research technique is to measure all significant variables and to indicate the momentary values with analog or digital indicating instruments. The measured values of particularly important variables are continuously recorded by means of dot or line plotters to reveal the value variations as a function of time. In large installations an instrumentation of this kind leads to such an expansion of control panels that the individual instruments, particularly in case of a malfunctioning, may no longer be entirely supervised and the measured values may be compared only with much difficulty.

Although the use of digital process calculators alleviates these difiiculties, it does not, however, effect a solution thereof. With a calculator all measured values of interest may be cyclically digitally measured and the digital values stored. It is sufficient hereby to store completely in a memory of short access time only the last measured values which, for example, were sensed during a period of a few hours. For the indication of the momentaneous values, the memory locations are called and the measured values of interest may be digitally indicated or printed. From such an indication, however, the variation of the measured magnitudes as a function of time may be established only with difficulty. This is particularly disadvantageous if, for example, in case of a malfunctioning, the trend of the data series is to be determined rapidly. For such a purpose, an analog plotting is substantially better adapted than a series of numerals, since a curve may be evaluated much faster and easier.

It is known (as set forth, for example, in German Published Pat. applications DOS No. 1,808,245) to use for the analog representation of measured values electronic analog visual apparatuses as readout devices of digital calculators for the indication of alphameric signs or for providing graphs wherein the curves are composed of dots on a screen with the aid of an electron beam. In known processes, for the representation of a new value, the curve already displayed is shifted in the direction of the time axis to provide a free location on the screen for the new value. Thus, the curve slowly travels across the screen and the newest measured value is always shown at the beginning of the curve. The oldest measured values disappear at the other screen edge.

OBJECT AND SUMMARY OF THE INVENTION The invention is based on the consideration that an installation may be better operated if not only the current values are represented, but there is also shown a corresponding desired value curve consisting, for example, of the measured values of the corresponding period of the previous day. The curves are so plotted that the desired values precede the actual values. In this manner the trend of the actual values is demonstrated and a timely interference may be effected concerning the course of the process.

Briefly stated, according to the invention, the actual and desired values are represented as graphs on the screen of a television set and further, the actual and desired values corresponding to one another are represented in the same line of the television screen. Also, the desired value curve extends across the entire area of the screen, whereas the actual value curve extends only over a part thereof. The newest actual values appear in a middle range of the screen area.

The invention will be better understood as well as objects and advantages will become more apparent from the ensuing detailed specification of several exemplary embodiments of the invention taken in conjunction with the drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a block diagram of an apparatus for practising the method according to the invention;

FIG. 2 is a circuit diagram of an image repeating memory for the desired and actual values;

FIG. 3 is a block diagram of an arrangement to determine the moment of release or readout of actual values with the aid of a shift counter;

FIG. 4 is a block diagram of a static image repeating memory;

FIG. 5 is a block diagram of a dynamic image repeating memory; and

FIGS. 6, 7 and 8 represent graphs of signal pulses to illustrate the operation of the dynamic image repeating memory shown in FIG. 5.

DESCRIPTION OF THE EMBODIMENTS Turning now to FIG. 1, there is shown a video apparatus l which receives signals from a pulse central 2. The apparatus 1 and the pulse central 2 are components of a commercially available conventional industrial television system. The pulse central 2 may be replaced by a light intensity amplifier which produces, from the digital light-dark signals, the signal (containing the image pulse, blanking pulse and synchronizing pulse) for the control of the video apparatus. The camera of the television system is replaced by a counter 20 (controlled by a beat generator 5), by two

comparator circuits

23 and 24 which compare the contents of the counter 20 with the contents of two

readout registers

21 and 22 and by two image repeating memories 4 and 4' which control the

readout registers

21 and 22. There is further provided an address or line counter 17 and a scale-down circuit 6. The latter forms, from the beatfrequency, the horizontal and the vertical scanning frequencies of the electron beam of the video apparatus 1 and controls the pulse central 2. There is further provided a work memory 7 which is associated with a process calculator and in which there are stored series of measured values from various measuring stations. If measured values from a certain measuring station are to be represented, then first the corresponding memory range of the process calculator has to be called. This is performed in the usual manner by giving a command by operating an appropriate control panel. Thereupon the process calculator transfers the measured values from the work memory 7 to the image repeating memories 4 and 4'. The number of the measured values is adapted to the storage capacity of the image repeating memories. After termination of the aforenoted transfer which, dependent upon the type of the

image repeating memories

4 and 4 and the work memory 7, lasts a few milliseconds at the most, the measured values are, during normal operation, cyclically transmitted from the image repeating memories 4 and 4' to the

readout registers

21 and 22, respectively. The contents of these registers are compared in the

comparator stages

23 and 24 with the contents of the counter 20. The latter counts upwardly by means of the beat pulses, with each line pulse as a start signal. Upon reaching the terminal position, it resets itself automatically and an admission of further beat pulses is blocked until a new start signal, that is, the successive line return pulse, appears. If one of the two

comparator stages

23 and 24 determines that the counter position is identical to the contents of a readout register, then it delivers a light pulse signal to the pulse central 2. Since the counter 20 counts through from until the terminal value, it is capable to pick up all values of data words in one series of counting. With such an arrangement, two curves may be simultaneously represented on the screen. The address counter 17 to which the horizontal deflecting pulses of the scale-down circuit 6 are applied, controls the inscription and readout into and from the image repeating memories 4 and 4'.

One of the two curves shown on the screen is the desired value curve, while the other is the actual value curve. The desired values may be, for example, the corresponding actual values of the previous day. Each desired value and its corresponding actual value should appear in the same line of the television picture. Therefore, the desired and actual values corresponding to one another are introduced in the same addresses of the memories 4 and 4'. If both memories are filled with values, then the newest actual value appears at the upper edge of the screen field standing by for the signal representation. Upon arrival of a new actual value, to which there corresponds a desired value still contained in the work memory 7, both curves are shifted by one line downwardly and the newest actual value and the associated desired value are introduced in the uppermost line. This method lends itself only to a comparison for determining to what extent the desired and actual values differ from one another. For the control of a process frequently it is much more advantageous to also know how the actual values will presumably change in the future. For this purpose even those desired values are utilized for which no corresponding actual values are still in existence. If the desired values are contained in the memory 4', then a determined number of additional desired values is introduced thereinto in such a manner that the addresses of the already stored desired values are increased by l and the new desired value is introduced into the memory cell with the lowest address. In this manner the desired value curve is shifted on the screen downwardly. Simultaneously, the addresses of the actual values in the memory 4 are also changed so that the beginning of the actual value curve is shifted downwardly on the screen of the video apparatus 1. If, for example, 200 lines are available for the representation of the curves and 100 additional desired values are inscribed, then the actual value curve begins in the middle of the screen. It is here assumed that for each actual value there exists a corresponding desired value. Otherwise, the corresponding desired value has to be first calculated. If a new actual value appears, then the latter is represented in the middle of the picture screen after the actual value curve has been shifted downwardly by one line. Simultaneously, a desired value is added to the desired value curve at the upper edge of the screen. Thus, both curves travel simultaneously downwardly with identical speed. The two curves have, in principle, a configuration shown in FIG. 1 on the screen of the video apparatus l. The right-hand curve which extends across the entire screen is the desired value curve while the lefthand curve which begins in the middle of the screen is the actual value curve.

In FIG. 2 there are shown exemplary circuits constituting the

image repeating memories

4 and 4. Basically, they comprise

shift registers

41, 41' and 42 in feedback connection. The shift registers contain inscribing and

readout registers

9, 9 and 10. After calling of the values from the work memory 7 of the process calculator, first the two memories are filled, for example, with 200 measured values each. Thereafter, additional values, for example, lOO in number, are introduced into the desired value memory. The shift registers 41' and 42 of the actual value memory 4 receive, for example, measured values each. Upon introduction of the 100 desired values, the values in the register 41' are shifted into the register 42 while the values in the register 42 are erased. Therefore, upon reproduction of the contents of both memories, the desired value curve extends across the entire screen while the actual value curve extends only across the lower portion thereof. The inscription of new desired and actual values in then controlled in such a manner that the desired values are inscribed through the inscribing register 9 in the shift register 41 while the actual values are inscribed through the inscribing register 10 in the shift register 42. The image repeating memory 4 may consist only of the shift register 42. in such a case the contents of the register 42 circulate twice during an image reproduction. During the first lap, the electron beam has to be controlled dark" for the actual value curve. This is achieved simply by blocking the output signal of the comparator 23 during the first lap of the circulating signal pulses. Such blocking may be controlled, for example, by the address counter 17. Accordingly, it is also possible not to extinguish the actual values already in the register 42 during inscription into the latter of the last l00 actual values, but to shift them into the shift register 41' and upon their reproduction to modulate the electron beam dark."

in the apparatuses described hereinabove, the lead of the desired value curve with respect to the actual value curve may be varied only with difficulty. HO. 3 illustrates an arrangement by means of which such a lead may be varied at will. The information lNF for the tie sired value memory 4 and for the actual value memory 4 is directed through an inscription control 16. The latter delivers the stepping pulses for the address and line counter 17, which, in turn, emits control pulses for the introduction and release of values into and from the memories 4 and 4'. With each desired value which is introduced into the memory 4' there is given a stepping pulse to a shift counter 19. A comparator l8 emits a starting signal for the readout of the actual values and for the moment of inscription of new actual values. If, for example, after both

memories

4 and 4 are filled, an additional 50 desired values are transferred into the memory 4', then the shift counter 19 has reached the count 50, provided it was previously set to zero. The line counter 17 which is set to zero with the image return pulses, reaches the position 50 with the fiftieth line of an image, and the comparator 18 transmits a control signal to the inscription control 16 which, in turn, emits a command signal for the readout of the actual values from the memory 4. The newest actual value will therefore appear in

line

50 or 51. In order to ensure that the beginning of the curves does not lie above the upper edge of the screen, the uppermost values of the curves are represented not in the first line but in a line of a higher order, for example, 51, so that the shift counter 19 is reset not to zero but to a higher number, for example, 51. The pulses, for example 50 in number, which the shift counter 19 summarizes upon inscription of additional desired values, are added to the preset number so that in the example, the newest actual value is represented in line 101.

The apparatus shown in FIG. 3 is adapted to compare two series of measured values plotted in the past. For this purpose, the two measured value series are again inscribed in the memories 4 and 4'. In order to be able to better compare the curves with one another, they should be relatively shiftable. For this purpose, the shift counter 19 is not switched when desired values are inscribed in the memory 4', but there is provided a beat generator 25 by means of which the position of the counter 19 can be varied. For the fine adjustment, the stepping pulses may be individually triggered in a manual manner, but, for a rapid shift of the desired value curve, they may be produced in a generator with an output frequency of, for example, cycles. In order to ensure that the desired value curve is shiftable in both directions, the counter 19 should be a forward and backward counter.

Turning now to FIG. 4, there is shown an extension of the arrangement illustrated in FIG. 3. In addition to the shift counter 19, the comparator 18 and the line counter 17, there is provided a second shift counter 27 and a comparator stage 26 which, in case of an identical position of counters l7 and 27, transmits a switch signal to one input of a trigger pair circuit BK, the other input of which of which is controlled by the comparator stage 18. This trigger pair circuit is incorporated in the inscription control designated with 16 in FIG. 3. From its output there is applied a release signal to a gate circuit T, to the other input of which there are applied the shift beat pulses for the actual value memory 4 which here again is expediently designed as a shift register. In the present case, the latter should be able to store only as many values as there are lines in the screen field where the curves are to be plotted. In any case, it has to be ensured that the shift register circulates only once during the reproduction of an image. This purpose is served by the counter 27 which in this embodiment is set to a number which, corresponding to the line number in the screen field, is by 200 higher than the number to which the counter 19 is preset. If, for example, the counter 19 is in position 51, then the counter 27 is in position 251. If then, there are introduced I00 values more into the desired value memory than into the actual value memory, the counter 19 will be in position 151 and the counter 27 in position 37 because, upon reaching position 314 which corresponds to the total number of lines in the image, it resets itself to 1. Upon reproduction of an image, accordingly, the trigger pair circuit BK, upon inscription of the one hundred fiftyfirst line, is switched and the gate T is set free for the shift beat pulse. The frequency of this beat pulse has a fixed relationship with respect to the line frequency to ensure that one desired value and one actual value is shifted into the readout register of the memories during a line period. After the scanning of 200 lines with the gate T open, the line counter reaches the count 37, the comparator 26 responds and switches the trigger pair circuit BK so that the gate T is again closed. Thus, in case of a storage capacity of 200 actual values, the values have circulated the memory exactly once. When the line counter again reaches count 151, the gate T is again opened and the first actual value is indicated in the one hundred fifty-first line. The arrangement; according to FIG. 4, serves for the control of the circulation of the actual values in the image repeating memory. The arrangement for the control of the circulation of the desired values in their circulation memory is similarly designed except that only a single counter is required for the beat pulses. To this counter there are connected two comparators of which one switches, at counter position 51, a trigger pair circuit, which at the counter position 251 is switched back by the other comparator. In the meantime a gate is opened for the beat pulses which shift the desired values in the image repeating memory.

Upon inscription of new desired and actual values, the oldest values have to be removed from the memories and replaced by the newest values whereby the newest values have to be represented at the beginning of the curve. Upon inscription of a new desired value in the desired value memory, the gate is closed when the shift counter reaches the position 250. The two hundred fifty-first measured value may then be written over with the newest value if at that moment the oldest measured value is in the inscribing and readout register. During the next lap, only the newest value can be represented in the line 51; it joins the curve at the upper screen edge. Simultaneously in order to ensure that both curves retain the same time relation the actual value curve also has to be provided at its beginning with its newest value. This is effected in the same manner as the introduction of the newest desired value, by closing the gate circuit T one line earlier for the best pulses which control the actual value memory. This is achieved by resetting by l the counter 27 (which is a forward and backward counter) and returning it to its old position after inscription of the new value.

In order to ensure that no actual values are represented in the image portion in which the desired value curve has a lead with respect to the actual value curve, in this portion the light intensity modulation for the actual value curve is turned off. The signal therefor may be obtained by superposition of the output signal of the trigger pair circuit BK with the signal which indicates the end (i.e., line 252) of the screen range used for the reproduction. Thus, light intensity modulation of the actual values occurs only from the starting moment for the shift pulses until line 251.

In the arrangement according to FIG. 4, circulation memories are used which may be arrested for a while and then may be restarted. Very often, however, the use of circulation memories should be possible in which the data circulate in a continuous manner. Such memories are, for example, plate, drum, or transit time memories. More recently, dynamic shift registers have been developed in the integrated MOS-technique which have a large capacity and small space requirement, but which require shift beat pulses with a minimum frequency below which the stored information may be lost. If the capacity of such a shift register is selected to be exactly of such a magnitude that the information to be represented may just be stored therein, then after the readout of the last word of a reproducing cycle the shift beat frequency must be blocked until the last image is inscribed. During such a period, however, the stored data may be lost. In FIG. there is shown the basic circuit diagram of an arrangement in which such image repeating memories may be used. Reference numerals 4 and 4' again indicate the desired value memory and the actual value memory, respectively. Since dynamic shift registers have to receive shift beal pulses continuously, the new measured values cannot be inscribed at an arbitrary moment between the reproduction of the last and the first represented measured values as it was possible, for example, in the arrangement according to FIG. 4. Thus, a new measured value is inscribed in the circulating shift register at a moment when the line counter 17 reaches the count or the address, as the case may be, of the memory cell in which the newest measured value has to be inscribed. This, for the desired value memory, is the measured value address 0 which in the present case corresponds to the line 50. A take-over pulse for the desired value memory thus occurs always synchronously with the writing of the line 50. The position 50 of the line counter 17 is determined by a line counter evaluating circuit 31 which then transmits a signal to the inscription control 16. The evaluation of the line counter position 50 also applies to the actual value memory if to the newest measured value thereof there is assigned the measured value address 0. This corresponds to a presetting of the shift counter 19 to the value 50. The evaluation is, however, taken over by the comparator 18. The representation of the measured values occurs from the measured value address 1, the content of which is represented in line 51. In order to complement the measured value curve in the afore-described manner with the newest measured values, the introduced measured values have to be re-addressed by one position after each inscription.

In the pulse diagram according to FIG. 6, the simultaneous inscription of desired and actual values is illustrated for the case when the inscribed values are to be represented in the same line. Upon inscription of a measured value in the memory cell of the desired value memory with the address 0, the addresses of all memory cells are increased by I so that the newest measured value will be represented in line 51. The same process takes place in the actual value memory if the newest value thereof is to be represented in the same line as the newest desired value.

In the description that follows, there will be set forth, with reference to the pulse diagram according to FIG. 7, how a lead of the desired value curve is effected with respect to the actual value curve by means of inscription of desired values. If desired values are introduced into the desired value memory as lead, then, on the one hand, take-over pulses UEB l are counted in the shift counter 19 and, on the other hand, signals MOD 1 and MOD 2 which effect the re-addressing in the desired value memory and in the actual value memory, are applied to both memories. In this manner the actual values are re-addressed by as many positions as there are advance desired values that were entered. The newest actual value is contained in that memory cell of the actual value memory, the address of which is determined by the position of the shift counter 19.

FIG. 8 illustrates a pulse diagram for the simultaneous inscription of desired values and actual values in the case when the desired value curve has a lead with respect to the actual value curve. ln this instance, the take-over pulses UEBl and UEB 2 arrive at different moments. The signal UEB I for the desired values arrives synchronously with the line 50, and the readdressing signal MOD 1 for the desired value memory begins with the address 0. The take-over signal UEB 2, on the other hand, arrives at a later moment, because it is generated only when the line counter 17 has reached the position of the shift counter 19. The readdressing signal MOD 2 for the actual value memory begins only after the arrival of the take-over signal UEB 2.

The choice among the three inscribing methods may be made by the calculator which introduces the corresponding indications into a function register 30 which, in turn, effects the routing of the pulses within the inscription control. If the actual value curve is erased through the function register, then, from this occurrence a resetting pulse is derived which returns the shift counter 19 to position 50.

A further operating mode may be desirable in a case set forth hereinbelow. The represented desired value of the previous day may have, for example, a particular course at a determined period. If the actual value curve shows a trend of a similar course, but for another point in time, then it is advantageous to be able to shift the curves in such a manner that the similar courses of the curves are disposed adjacent or in superposition with respect to one another. For this purpose, the shift counter 19 is formed as a forward and backward counter. The attendant may now apply counting pulses through the function register 30 to the shift counter 19, and simultaneously apply, in an identical number, addressing signals to the actual value memory. In response, the actual value curve shifts on the screen in the desired direction. If, subsequently, the newest measured values are introduced, then, again, the inscription address is determined for the actual values by the position of the shift counter 19.

What is claimed is:

l. A method of comparing digitally presented actual and desired values, comprising the steps of A. displaying a series of desired values as a curve extending across the entire field of a television screen,

B. displaying a series of actual values as a curve extending solely across one part of said field,

C. adding the newest actual values to the actual display of the value curve at a midportion of said field and D. orienting the respective curves so that mutually corresponding actual and desired values are displayed in the same and-raster line of the television picture.

2. A method as defined in claim 1, including the steps A. inscribing, at the beginning of curve representation, the desired values and the actual values in two separate and similar image repeating memories; mutually corresponding actual and desired values are inscribed in memory cells with the same address,

B. cyclically applying said actual and desired values from said image repeating memories to a video apparatus including said television screen,

C. subsequently inscribing a predetermined amount of desired values in the image repeating memory for desired values,

D. shifting the actual values in said image repeating actual value memory with respect to the addresses by the same amount and extinguishing the same amount of actual values inscribed therein substantially contemporaneously with said step of subsequently inscribing,

E. shifting the stored actual and desired values by one memory location for inscribing new actual and desired values,

F. inscribing the new desired value in the vacated memory location with the lowest address and G. inscribing the new actual value in the vacated memory location with an address higher than that assigned to the previous most recent actual value.

3. A method as defined in claim 1, including the steps A. inscribing, at the beginning of curve representation, the desired values and the actual values in two separate and similar image repeating memories; mutually corresponding actual and desired values are inscribed in memory cells with the same address, I

D. shifting, simultaneously with the step set forth precedingly, the actual values in the image repeating memory for actual values with respect to the addresses by the same amount,

E. modulating dark" the electron beam plotting said curves on the television screen upon representation of the contents of the memory cells with the addresses by which the newest actual value has been shifted,

F. shifting the stored actual and desired values by one memory location for inscribing new actual and desired values,

G. inscribing the new desired value in the vacated memory location with the lowest address and H. inscribing the new actual value in the vacated memory location with an address higher than that assigned to the previous most recent actual value.

4. A method as defined in claim 1, including the steps of A. inscribing, at the beginning of curve representation, the desired values and the actual values in two separate and similar image repeating memories; mutually corresponding actual and desired values are inscribed in memory cells with the same address,

D. shifting, simultaneously with the step set forth precedingly, the actual values in said image repeating memory for actual values with respect to the addresses by the same amount and extinguishing the same amount of actual values inscribed therein.

F. inscribing the new desired value in the vacated memory location with the lowest address,

G. inscribing the new actual value in the vacated memory location with an address higher than that assigned to the previous most recent actual value,

H. counting by means of a shift counter and without a simultaneous inscription of actual values in the image repeating memory for actual values the number of desired values introduced into the image repeating memory for the desired values,

I. comparing the contents of said shift counter with the contents of a line counter and J. beginning the representation of the actual values when identity between the contents of said shift counter and said line counter is reached.

5. A method as defined in claim 1, including the steps A. inscribing, at the beginning of curve representation, the desired values and the actual values in two separate and similar image repeating memories; mutually corresponding actual and desired values are inscribed in memory cells with the same address,

B. cyclically applying said actual anddesired values from said image repeating memories to a video apparatus including said television screen,

G. inscribing the new desired value in the vacated memory location with the lowest address,

H. inscribing the new actual value in the vacated memory location with an address higher than that assigned to the previous most recent actual value,

I. counting, by means of a shift counter, and without a simultaneous inscription of actual values in the image repeating memory for actual values the number of desired values introduced into the image repeating memory for the desired values,

J. comparing the contents of said shift counter with the contents of a line counter and K. beginning the representation of the actual values when identity between the contents of said shift counter and said line counter is reached.

6. An apparatus for comparing actual and desired values comprising:

A. a video apparatus including a picture screen,

B. an image repeating memory for actual values,

C. an image repeating memory for desired values; the number of memory cells in each memory being less than the number of lines in the television picture on said screen,

D. a line counter,

E. a trigger pair circuit,

F. a shift counter,

G. a first comparator circuit transmitting a setting signal to said trigger pair circuit when the contents of said shift counter and said line counter are identical,

H. a further counter controlled parallel with said shift counter and preset to a number which is greater by the number of memory cells than the number to which said shift counter is set,

. a second comparator circuit transmitting a resetting signal to said trigger pair circuit when the contents of said line counter and said further counter are identical and .l. a gate circuit connected to said trigger pair circuit and opened by the latter when in a set position to aliow passage of shift beat pulses to said image repeating memory for actual values.

7. An apparatus for comparing actual and desired values comprising:

B. an image repeating memory for actual values,

C. an image repeating memory for desired values; the number of memory cells of the memories being larger than the number of values to be stored and, at the most, being identical to the number of lines in the picture on said television screen,

D. a line counter,

E. a shift counter,

F. comparison circuit means coupled to respective outputs from said line counter and said shift counter for producing a control signal whenever the outputs from said line counter and said shift counter are equal, and

G. an inscription control circuit means coupled from said comparison circuit means and to each of said image repeating memories, to an input of said line counter and to an input of said shift counter for transmitting to effect the inscription of a desired value and an actual value, a take-over signal to said image repeating memory for desired values and to said shift counter at the moment when the line is written in which the first value of the desired value curve is plotted and for transmitting a take-over signal, in response to the control signal from said comparison circuit means, to said image repeating memory for actual values when the contents of said line counter and said shift counter become identical

Claims

1. A method of comparing digitally presented actual and desired values, comprising the steps of A. displaying a series of desired values as a curve extending across the entire field of a television screen, B. displaying a series of actual values as a curve extending solely across one part of said field, C. adding the newest actual values to the actual display of the value curve at a midportion of said field and D. orienting the respective curves so that mutually corresponding actual and desired values are displayed in the same and-raster line of the television picture.

2. A method as defined in claim 1, including the steps of A. inscribing, at the beginning of curve representation, the desired values and the actual values in two separate and similar image repeating memories; mutually corresponding actual and desired values are inscribed in memory cells with the same address, B. cyclically applying said actual and desired values from said image repeating memories to a video apparatus including said television screen, C. subsequently inscribing a predetermined amount of desired values in the image repeating memory for desired values, D. shifting the actual values in said image repeating actual value memory with respect to the addresses by the same amount and extinguishing the same amount of actual values inscribed therein substantially contemporaneously with said step of subsequently inscribing, E. shifting the stored actual and desired values by one memory location for inscribing new actual and desired values, F. inscribing the new desired value in the vacated memory location with the lowest address and G. inscribing the new actual value in the vacated memory location with an address higher than that assigned to the previous most recent actual value.

3. A method as defined in claim 1, including the steps of: A. inscribing, at the beginning of curve representation, the desired values and the actual values in two separate and similar image repeating memories; mutually corresponding actual and desired values are inscribed in memory cells with the same address, B. cyclically applying said actual and desired values from said image repeating memories to a video apparatus including said television screen, C. subsequently inscribing a predetermined amount of desired values in the image repeating memory for desired values, D. shifting, simultaneously with the step set forth precedingly, the actual values in the image repeating memory for actual values with respect to the addresses by the same amount, E. modulating ''''dark'''' the electron beam plotting said curves on the television screen upon representation of the contents of the memory cells with the addresses by which the newest actual value has been shifted, F. shifting the stored actual and desired values by one memory location for inscribing new actual and desired values, G. inscribing the new desired value in the vacated memory location with the lowest address and H. inscribing the new actual value in the vacated memory location with an address higher than that assigned to the previous most recent actual value.

4. A method as defined in claim 1, including the steps of A. inscribing, at the beginning of curve representation, the desired values and the actual values in two separate and similar image repeating memories; mutually corresponding actual and desired values are inscribed in memory cells with the same address, B. cyclically applying saiD actual and desired values from said image repeating memories to a video apparatus including said television screen, C. subsequently inscribing a predetermined amount of desired values in the image repeating memory for desired values, D. shifting, simultaneously with the step set forth precedingly, the actual values in said image repeating memory for actual values with respect to the addresses by the same amount and extinguishing the same amount of actual values inscribed therein. E. shifting the stored actual and desired values by one memory location for inscribing new actual and desired values, F. inscribing the new desired value in the vacated memory location with the lowest address, G. inscribing the new actual value in the vacated memory location with an address higher than that assigned to the previous most recent actual value, H. counting by means of a shift counter and without a simultaneous inscription of actual values in the image repeating memory for actual values the number of desired values introduced into the image repeating memory for the desired values, I. comparing the contents of said shift counter with the contents of a line counter and J. beginning the representation of the actual values when identity between the contents of said shift counter and said line counter is reached.

5. A method as defined in claim 1, including the steps of A. inscribing, at the beginning of curve representation, the desired values and the actual values in two separate and similar image repeating memories; mutually corresponding actual and desired values are inscribed in memory cells with the same address, B. cyclically applying said actual and desired values from said image repeating memories to a video apparatus including said television screen, C. subsequently inscribing a predetermined amount of desired values in the image repeating memory for desired values, D. shifting, simultaneously with the step set forth precedingly, the actual values in the image repeating memory for actual values with respect to the addresses by the same amount, E. modulating ''''dark'''' the electron beam plotting said curves on the television screen upon representation of the contents of the memory cells with the addresses by which the newest actual value has been shifted, F. shifting the stored actual and desired values by one memory location for inscribing new actual and desired values, G. inscribing the new desired value in the vacated memory location with the lowest address, H. inscribing the new actual value in the vacated memory location with an address higher than that assigned to the previous most recent actual value, I. counting, by means of a shift counter, and without a simultaneous inscription of actual values in the image repeating memory for actual values the number of desired values introduced into the image repeating memory for the desired values, J. comparing the contents of said shift counter with the contents of a line counter and K. beginning the representation of the actual values when identity between the contents of said shift counter and said line counter is reached.

6. An apparatus for comparing actual and desired values comprising: A. a video apparatus including a picture screen, B. an image repeating memory for actual values, C. an image repeating memory for desired values; the number of memory cells in each memory being less than the number of lines in the television picture on said screen, D. a line counter, E. a trigger pair circuit, F. a shift counter, G. a first comparator circuit transmitting a setting signal to said trigger pair circuit when the contents of said shift counter and said line counter are identical, H. a further counter controlled parallel with said shift counter and preset to a number which is greater by the number of memory cells than the number to Which said shift counter is set, I. a second comparator circuit transmitting a resetting signal to said trigger pair circuit when the contents of said line counter and said further counter are identical and J. a gate circuit connected to said trigger pair circuit and opened by the latter when in a set position to allow passage of shift beat pulses to said image repeating memory for actual values.

7. An apparatus for comparing actual and desired values comprising: A. a video apparatus including a picture screen, B. an image repeating memory for actual values, C. an image repeating memory for desired values; the number of memory cells of the memories being larger than the number of values to be stored and, at the most, being identical to the number of lines in the picture on said television screen, D. a line counter, E. a shift counter, F. comparison circuit means coupled to respective outputs from said line counter and said shift counter for producing a control signal whenever the outputs from said line counter and said shift counter are equal, and G. an inscription control circuit means coupled from said comparison circuit means and to each of said image repeating memories, to an input of said line counter and to an input of said shift counter for transmitting to effect the inscription of a desired value and an actual value, a take-over signal to said image repeating memory for desired values and to said shift counter at the moment when the line is written in which the first value of the desired value curve is plotted and for transmitting a take-over signal, in response to the control signal from said comparison circuit means, to said image repeating memory for actual values when the contents of said line counter and said shift counter become identical.