CA1049152A - Methods of improving the measure and display precision in an arrangement for interrogating and representing several values to be measured - Google Patents

Abstract

Methods Of Improving The Measure And Display Precision In An Arrangement For Interrogating And Representing Several Values To Be Measured Abstract of the Disclosure This invention provides a method of improving the measure and dis-play precision in an arrangement for interrogatinq several values to be measured which are picked up by input/output devices or service proces-sors of a computer system, and generally by discrete and discretely ad-dressable functional units, where the individual functional units are connected to an address channel and predetermined addresses are associ-ated thereto, and where furthermore the individual functional units are connected to a measure data channel via which, after addressing and switchinq, data are transferrable to a central location, and where for the time representation of these measure values on a display device, all desired measure positions of the one service processor selected by means of the selected address being switched simultaneously via the central measure data channel with a central measuring processor, a trigger signal supplied by the selected service processor and applied on a measure data channel line is selectable for synchronization, this trigger signal fur-thermore causing the central measuring processor to start interrogating in predetermined intervals all measure data signals on the measure data channel simultaneously, and where finally the momentary measure values in that interrogation are stored in a storage and displayed in parallel and simultaneously in different lines on the alphanumeric screen used as display device with column and line representation, the screen having a storage where all characters displayed on the screen can be stored and used again and again for display, and where each column of the screen has an associated interrogation pulse, characterized in that upon each second newly triggered cycle the interrogation pulses, relative to the interrogation pulses of the preceding cycle, are staggered as a whole with respect to time, said time staggering being relatively small regard-ing the spacing of two interrogation pulses.

Description

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1 The invention relates to me~hods of improving the measure and display precision in an arrangement for interrogating several values to be measured which are picked up by input/output devices or service processors of a computer system, and generally by discrete and discretely addressable func- -tional units, where the individual ~unctional units are connected to an address channel and predetermined addresses are associated thereto, and where furthermore the individual functional units are connected to a measure data channel via which, after addressing and switching, data are transferrable to a central location, and where for the time representation of these measure values on a display device, all desired measure positions of the one service processor selected by means of the selected address being switched simultan-eously via the central measure data channel with a central measuring processor, .
a trigger signal supplied by the selected service processor and applied on a measure data channel line is selectable for synchronization, this trigger .
signal furthermore causing the central measuring processor to start interro-gating in predetermined intervals all measure data signals on the measure ~ .
data channel simultaneously, and where finally the momentary measure values in that interrogation are stored in a storage and displayed in parallel and simultaneously in different lines on the alphanumeric screen used as display device with column and line representation, the screen having a storage where all characters displayed on the screen can be stored and used again and again -.
for display, and where each column of the screen has an associated interro-gation pulse, in accordance with commonly assigned U.S. Patent 3,818,201 issued June 18, 197~. ;
In the practical application of the above specified arrange- - ~ `
ment in accordance with the aforesaid U.S. patent it has become evident in some applications that the precision of display needs improvement. This applies particularly to those cases where the time basis used for the inter-rogation and display of the measure values is 30~s. There, after the expir-ation of 30~s, a new interrogation pulse STROBE is generated interrogating ., . , .. - . . . . : . .
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If for instance the pulse on the measure data channel appears directly prior to the following interrogation pulse the measure value to be read on the screen is shown too small by almost the entire distance of two interrogation pulses.
Another problem is that the interrogation in relation to the trigger slope causes a certain synchronization loss in the interrogation loop to be passed through. Thus, the measuring precision at the moment of trigger- -ing is not as high as it should be, particularly when measuring short pulses with the smallest time basis.
It is the object of the present invention on the one hand to design the arrangement in such a manner that the measure and display precision at the slope of a pulse is increased, and on the other to increase the measur-ing precision with respect to the synchronization losses.
The object of improving the measure and display precision at the slope of a pulse is achieved, in an arrangement of the kind specified above, when upon each second newly triggered cycle the interrogation pulses, relative to the interrogation pulses oF the preceding cycle, are staggered as a whole with respect to time, said time staggering being relatively small regarding the spacing of two interrogation pulses.
By means of this periodic shifting back and forth, and owing to certain time staggering of the scanning pulses of various cycles the ~- -, ' ' .

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Thus, the slope of a pulse can be detected quite precisely and exactly.
Of course, this applies analogously to the beginning of a pulse. If the arrangement with this method is used for adjustment purposes the adjustment can be altered in such a way that the pulse end coincides exactly with an interrogation pulse, which is represented by the lighting up of both the vertical and the horizontal display dash.
It is to be noted here that in this specific display position the symbols shown are displayed with half the lighting-up force because they are displayed on the screen in every second cycle only. If in an adjustment a pulse slope is to be set to a discretionary position be- -~
tween two successive interrogation pulses this can be performed by means of an iteration process, in consideration of the adjustment range with corresponding setting of the adjustment. There exist two means for attaining the object of increasing the measuring precision with respect to the compensation of the synchronization loss in the above specified ~
arrangement. `
The first means is characterized in that the interval, i.e.
the time basis, between the appearance of the trigger signal and the following emission of the first interrogation pulse to be displayed and the second displayed interrogation pulse is shortened by the medium statistical time loss in the synchronization loop, i.e. by approximately half the cycle time of the synchronization loop, and that the measure values observed at the trigger moment are buffered and, upon the appear-ance of the first interrogation pulse, displayed by the latter on the screen in the 0-column.
The second means is characterized in that the column position associated to thé synchronization point, i.e. the 0 position, with its ; , .

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1 corresponding measure values is not displayed on the screen, and that the period between the ideal moment of synchronizations i.e., the slope change, and the first interrogation pulse initiating the interrogation and display of the measure values ;c corrected by a time correction unit in cooperation with the time basis generator, with respect to time exactly onto the time basis, the time correc-tion unit being activated only after the appearance of the deter-mined synchronization signal.
An advantageous and practical embodiment of the methods accord-ing to the invention and the arrangement disclosed in U.S. Patent3,818,201 consists in that apart from the normal trigger signal an-other signal of the other measure value signals relevant with re-spect to the measuring can be selected and used for synchronization, said signal activating normal triggerina upon selection and avail-ability~ ;
Below, the operation of the methods according to the inventionare specified by means of the Figures which show the following:
Fig. 1 is a schematic view illustrating the sequence synch-ronization, detection and translation of the measure values for their display on the screenj Fig. 2 shows various schematic pulse and display representations;
Fig. 3 is a schematic view illustrating the chronological sequence followed in the first solution for correcting the synchronization loss;
Fig. 4 is a schematic view illustrating the chronological se-quence followed in the correction of synchronization losses according to the second solution; and Fig. 5 is a schematic view illustrating a sequence in a use of an additional triggering reference signal.
Fig. 1 shows a part of the sequence covering that section of syn-chronization and measuring phase of interest in this conrection. Thisfigure shows the essertial features of Fig. 2 of the aforesaid U.S.
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1 It is detected in branching 36 whether the trigger slope changes from minus .
to plus, and in branching 40 whether the trigger slope changes from plus to minus. As long as this is not the respective case this second synchroniza-tion loop, which loop can also be called synchronization waiting loop, has to be passed through again and again via the corresponding No-lines. If the desired change is detected in one of these cycles a branching to the respective Yes-lines is made, and within this sequence branching 42 is reached where it is detected whether or not there is a scanning end. As this is involved in each respective case of the beginning of a scanning, a transition is made at branching 42 via the No-line into the actual measuring phase to the part marked 43 representing the scanning pulse generator for generating the STROBE pulses. Thus, by the signal arriving via the No-line of branching 42 a scanning pulse marked STROBE is emitted at 43. By means of the STROBE pulse at the output of 43 the simultaneous storing of the individual measure values is perFormed at 44, on the one hand, and on the other simultaneously and in parallel detected measure values are translated for display on the screen. When this has been done the program passes on to time basis generator 50 in order to ensure the observing of the selected time basis. The further sequence then returns again to branching 42 and consequently to the renewed generation of a STROBE pulse if there is no scan-ning end. Consequently, scanning and displaying the measure values is repeated until all characters displayable in one line on screen 12 have been displayed. In the embodiment of the invention, 51 character positions in one line on screen 12 are provided.
As shown in Fig. 1, there is a certain loss of time in the two ~ 7 loops marked 36 and 40, at the beginning of the representation of a line, upon the interrogation to the trigger slope whether it passed to the positive or to the negative value. In the statistical mean value there is a loss of time here amounting to half the cycle duration approximately for the passing through the respective loop. This, however, occurs only in the represen-~. "' .
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tation for the very first character position of a line.
In Figs. 2A to 2C various pulse diagrams are given schematically, the respective top line showing analogously a pulse 61 to be represented, the second line beneath it representing by small arrows 64 ~he scanning pulses marked STROBE which always repeat in the interval of the time basis the scanning of the measure value to be displayed, and the third line showing the display on screen 12, said display being realized by horizontal 62 and vertical 63 dashes. A horizontal dash 62 means that the measure value is not available at this scanning moment, and the ver-10 tical dash means that the measure value is available at this scanningmoment, i.e., the appearance of a STROBE pulse, or that the level values of the measure value signals show significant differences, respectively.
Fig. 2A shows a pulse diagram by means of which the problem of the display precision at the end of a pulse is to be specified. In the top line an analogous pulse 61 is shown whose length is no integral multiple of the spacing o~ the STROBE pulses marked 64, or whose slope end does not coincide with a scanning pulse, respectively.
STROBE pulses 64 are shown in the center line of Fig. 2A, and the lo~er line shows those dashes which represent the display upon the pre-20 sence or absence, or the significant level value differences of theanalogous signal during the appearance of the STROBE pulses. A horizon-tal dash 62 indicates the absence, i.e., one level value of such a pulse, and a ~ertical dash 63 indicates the presence, i.e., the other level Yalue of the pulse upon the appearance of a STROBE pulse 64. 65 represents the residual pulse time which is seriously affecting, and which occurs in, those cases where analogous pulse 61 does not precisely coincide with one of STROBE pulses 64, and ends shortly before the appearance of a next STROBE pulse. As shown by the display with the yertical dashes 63 in the lower l ine of Fig. 2A, these vertical dashes 30 63 indicate a too short pulse.
Fig. 2B, contrary to Fig. 2A, represents the case that ana-GE~-73-014 - 7 . -: .., ." . . .
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In Fig. 2C, the operation of the solution according to the invention is shown by means of a pulse diagram similar to those of Figs. 2A
and @2B. By 64, in the form of small through-going arrows, the STROBE pulses are shown scanning in regular intervals analogous pulse 61. This applies to the one cycle, i.e. for all interrogation pulses STROBE which occur from the appearance of the trigger signal at the beginning oF a line represen-tation to the end of this line representation. Marked 64' and provided adjacent thereto small dashed arrows are shown equally symbolizing the STROBE pulses, but in the subsequent cycle. These pulses 64' are slightly staggered, with respect to time, relative to pulses 64. This has the effect that the interrogation of the analogous pulse 61 takes place lat~r or sooner by the amount of said staggering. If in a cycle which corresponds to STROBE
pulses 64 the end of analogous pulse 61 has not yet passed vertical dash 63 in Fig. 2C indicates the presence of pulse 61. In the next cucle, with staggered STROBE pulses 64', it is assumed that the end of analogous pulse 61 has just passed so that the corresponding STROBE pulse does not find a high measure value level any longer. Thus, a horizontal dash 62 is dis-played on the screen at the same spot where in the preceding cycle there had been a vertical dash 63. Consequently, there is a double display on the screen in one and the same character or column position consisting of a horizontal dash 62 and a vertical dash 63, when the end of analogous pulse 61 just happens to fall, with respect to time, between the two STROBE pulses 64 and 64'. Owing to the fact that at each second newly triggered cycle STROBE pulses 64' as a whole are slightly staggered, with respect to time, relative to STROBE pulses 64 of the preceding cycle, with the same respective interval being maintained, it is possible to state clearly . ' :
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1 whether there is a pulse end. Should it be necessary that the pulse end isto reach a position between two STROBE pulses the user, by means of deter-mining his adjustment range between two successive STROBE pulses 64, and correspondingly setting the adjustment, can reach the desired intermediate position.
When highly precise measurings of short pulses at the smallest possible time basis of for instance 30 microseconds are to be made the syn-chronization time loss in the trigger loop has a negative influence. This time loss occurs in synchronization loops 36 or 40, respectively, (cp. Fig.
1~ because this loop has a respective predetermined cycle time and because the synchronization, i.e. the change of the trigger slope from plus to minus or vice versa from minus to plus, cah occur on the one hand directly after -the interrogation in the loop, or on the other shortly before the interro-gation through the synchronization loop. In continuous measurings there is a medium synchronization time loss which corresponds approximately to half the cycle time of a trigger loop 36 or 40, respectively. In accordance with the invention, the compensation or correction of these synchronization time losses can be performed in two different ways.
By means of Fig. 3 representing a schematical course with ;
respect to time of the synchronization and the display of the first charac-ter positions on the screen the first means of solution will be explained ;n detail. 36, 40 represent the branching where the interrogation for the presence of the slope change of the trigger signal is made. If the trigger signal is not present the synchronization loop is once more passed through, which is represented by the No-line returning to the input of loop 36, 40. If, however, synchronization, i.e. the slope change, is found the output marked "YES" of branching 36, 40 is activated. Simultaneously with the setting of the Yes-output of the synchronization loop all measure values ' - available at that moment are stored in a storage JO. Furthermore, the ~ -~
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sz 1 to generate the scanning pulses STROBE (cp. Fig. 1). Upon the ap-pearance of the first STROBE pulse the display of the detected measure values in the very first character position on the screen is activated.
This is shown in Fig. 3 by box 120 with the "O" entered therein. For the display of the horizontal or vertical dashes 62 or 63, respectively, of this "O" position of the various lines of screen 12 a predetermined period of time is required. After the termination of the translation and display of the corresponding measure values, cp. also 44 in Fig. 1, time basis generator 50 is normally addressed. Now, however, the loss of synchronization time is to be compensated, so that the normally existing stop time basis generator 50 would be too long for observing the exact time basis interval between the arrival of the synchronization signal and the interrogation and display of the measured contents con-nected w1th the next STROBE pulse. For these reasons, a time basis correction is executed after the display of the values in the "O" posi-tion, at 120 by an element 71. The maintaining of the exact time basis of for instance 30 microseconds is shown in Fig. 3 by the spacing from the middle of the synchronization loop 3~, 40 to the beginning of box 121. This reference 121 symbolizes the appearance of the next STROBE
pulse for the associated column position "1" on screen 12. After the expiraiion of the time required for the translation and display on the screen (cp. 44 1n Fig. 1), time basis generator 50 is addressed, and ~hen it has been passed through with the correct time basis the measure values for position "2" are represented at 122. The exact time basis between the individual STROBE pulses or the beginning of the display of the individual positions at 121 and 122, respectively, equals the same time basis between the exact position, assumed in the middle of branching 36, 40, of the trigger moment and the beginning of the display of posi-tion "1" at 121. Therebetween there is the display of the "O" position at 120.
By the storing of the measure values at 70 at the moment of deter-mining the conditioning of synchronization loop 36, 40 and the correc-GE9-73-014 - lo -. ' , .
-3~0~1L9~S2 l tion of the time basis at 71 between the moment of synchronization 2nd the next interrogation pulse it is ensured that the measuring precision is much higher with short pulses and upon the use of the minimum time basis.
By means of the course of events shown schematically with respect to time in Fig. 4 the second possible solution for correcting the loss of synchronization time is represented. 36, 40 again represents the synchronization 1Q^P which in+errogates whether or not there is the synchronization slope. If it has been found in a cycle that the syn-chronization slope had appeared the Yes-line of the branching is set and connected to a time correcting unit 75, and after the expiration of the correction time, time basis generator 50 is addressed where a stop is made until the exact time basis of again for instance 30 microseconds has expired.
The time correcting unit 75 may consist of a sequent;ally operated delay circuit in which a first. pulse received by the unit is transmitted through the unit 75 undelayed whereas a second pulse is transmitted ~
through the unit 75 with some marginal delay. A delay of 10% of the ;
cycle time would be appropriate. By this means the first cycle of strobe pulses is initiated by the synchronization slope 36, 40 directly upon the receipt of a slope signal whereas the second cycle of strobe pulses is initiated after the predetermined delQy of the receipt of a slope signal set by the delay circuit. The next or third cycle is synchronized with the slope s1gnal and the fourth signal is delayed.
This operation of alternate delayed and non-delayed strobe cycles con-tinues throughout the scanning and display of measurable signals on ~ ;~
CRTl2. Then, the STROBE pulse is emitted at 43 (cp. Fig. l) which stores measure values at the measure data channel, translates them, and displays them on the screen. The values to be displayed with this STROBE pulse are displayed at 121' in position "l" of screen 12. After the ~xpiration of the display time, time basis generator 50 is again ; passed through, and a~ter the expiration of the time basis another GE9-73-014 ~ - ll -... ... .

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1 scanning pulse STROBE is emitted at 122' interrogating the measure values and displaying them in position "2" of the various lines of screen 12. In this second solution it is essential to point out that the "O" position on screen 12 is not shown in the inc!ividual lines of measure values TO, Sl, S2, anc! S3. The first display appearing on the screen takes place in the subsequent position, that jc the "1" position corresponding to column 1 on the screen. By means of this s~lution, time correction 75 and passing through time basis generator 50 ensure exactly that time basis as a whole which also corresponds to the time basis between the STROBE pulses which correspond to positions "1" and "2". The time between the ideal moment of synchronizaticn which in Fig. -4 has been selected in the middle of branching 36, 40, and the beginning of the display "1" position consequently eauals the desired time basis.
This, toc~, considerably increases GE9-73-014 - 11 a -A ~

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1 the measuring precision.
By means of Fig. 5, another advantageous embodiment of the various methods according to the invention and of the arrangement according to the main application will be described. In that respect, the represen-tation in Fig. 5 has been much simplified and is given schematically.
Triggering the various measurings is normally performed with the signal marked T0, or more precisely with its slope, as selected, upon the change from plus to minus or from minus to plus. In some measurings it is desirable to initiate tr;ggering only when there appears another signal ~;
which is relevant for the measuring.
As a signal relevant for the measuring one of signals Sl to S3 can be selected. In order to find out whether one of signals Sl to S3 is i--to be used as an additional trigger signal beside trigger signal T0, an interrogation is made in branchings 77, 78 and 79 for the use of these sig-nals as trigger signals. If one of these signals has been selected as trigger signal by means of the keyboard as an additional trigger signal another respective branching is addressed via the Yes-lines, signals Sl to S3 being subsequently interrogated in these branchings 80, 81, and 82 whether there is the necessary level which had also been determined by means of 2Q keyboard input. If the necessary level is present at one of branchings 80 to 82 and the corresponding additional trigger signals Sl to S3 the measuring by normal triggering with signal T0 is initiated when the selected slope change has been found at branching 36, 40. If th;s is the case the measuring at 85 is initiated by this branching 36, 40 via the Yes-line.
If the measuring at 85 has reached the end of a line on the screen another interrogation is made at 77 for the presence of additional trigger signals, and besides for the presence of the normal trigger slopes at 36, 40. Thus, the entire triggering and measuring is cyclically repeated. If at branch-ings 77 to 79 there is no respective keyboard input to an additional trig-gering the measuring process is executed via the No-line at branching 79 ,, .,, , ~ ................... ... .... .. .

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This above-described additional triggering permits to synchron-ize the desired measuring oscillogram, in spite of frequently reappearing trigger slope T0, although with the latter but at a discretionary moment, i.e. when a signal which is relevant for the measuring is available addition-ally.
As a possible use for this additional triggering reference is made to measurings in card units. There is a continuously operating time indicator the signals of which are normally used as trigger signals T0.
Measuring is now to take place in a specific mode of operation, for instance in the transport mode, the punch mode, the read mode, or in the print mode.
A signal relevant for these modes is applied to signal inputs Sl to S3 and selected via keyboard input. Furthermore, the desired level which will then be detected in branchings 80 to 82 will then be selected via keyboard input.
The beginning of the measuring is triggered at that moment when one of the signals significant for the measuring, i.e. one of signals Sl to S3, are present and when furthermore the selected trigger slope T0 is found at branchings 36 or ~0, respectively.
The cyclical staggering of the interrogation pulses, according to the invention, upon each second newly triggered cycle advantageously permits an essential improvement of the display of pulse slopesi furthermore the compensation of the loss of synchronization time at the beginning of a respective newly triggered measuring and display considerably increases the display and measure precision, and finally a possible additional triggering substantially increases the flexibility and precision of the informative contents of the entire measuring and display arrangement.

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Claims (4)

The embodiments of the invention in which an exclusive property or privilege is claimed are as follows:

1. A method of improving the measure and display precision in an arrangement for interrogating several values to be measured which are picked up by input/output devices or service processors of a computer system, and generally by discrete and discretely addressable functional units, where the individual functional units are connected to an address channel and predeter-mined addresses are associated thereto, and where furthermore the individual functional units are connected to a measure data channel via which, after addressing and switching, data are transferrable to a central location, and where for the time representation of these measure values on a display device, all desired measure positions of the one service processor selected by means of the selected address being switched simultaneously via the central measure data channel with a central measuring processor, a trigger signal supplied by the selected service processor and applied on a measure data channel line is selectable for synchronization, this trigger signal furthermore causing the central measuring processor to start interrogating in predetermined intervals all measure data signals on the measure data channel simultaneously, and where finally the momentary measure values in that interrogation are stored in a storage and displayed in parallel and simultaneously in different lines on the alphanumeric screen used as display device with column and line represen-tation, the screen having a storage where all characters displayed on the screen can be stored and used again and again for display, and where each column of the screen has an associated interrogation pulse, characterized in that upon each second newly triggered cycle the interrogation pulses, relative to the interrogation pulses of the preceding cycle, are staggered as a whole with respect to time, said time staggering being relatively small regarding the spacing of two interrogation pulses.

2. A method as claimed in Claim 1 characterized in that the interval between the appearance of the trigger signal and the following emission of the first interrogation pulse to be displayed and the second displayed interrogation pulse is shortened by means of a time basis correction unit by the medium statistical time loss in the synchronization loop and that a storage is provided where the measure values existing at the moment of appearance of the detected synchronization signal are buffered and, upon the appearance of the first interrogation pulse displayed by the latter on the screen in the "0" column.

3. A method as claimed in Claim 1 characterized in that the col-umn position associated to the synchronization point with its corresponding measure values is not displayed on the screen and that the period between the ideal moment of synchronization and the first interrogation pulse is corrected by a time correction unit in cooperation with the time basis gene-rator with respect to time exactly onto the time basis, the time correction unit being activated only after the appearance of the determined synchroni-zation signal on the Yes-line of the branchings.

4. A method as claimed in Claims 2 or 3, characterized in that apart from the normal trigger signal another signal of the` other measure value signals relevant with respect to the measuring can be selected and used for synchronization, said signal activating normal triggering upon selection and availability.