DE4427007A1 - Transmitting hardware pulses from source to receiver units along data bus or line - Google Patents

Abstract

Each flank (F0, F1) of a hardware pulse is transmitted in the form of a data value (D0, D1) containing information about the flanks in the code. A dead time (T20, T21) is detected and this in coded form is also included in the data value, and transmitted in a specific time (Tii), known to the transmitter and receiver. A total dead time (delta T0, delta T1) is found and corrected by the receiver and finally evaluated.

Description

The invention relates to a method for the line bound transmission of hardware pulses from one source to a receiving device.

For example, in modern industrial controls wise with machine tools or robots often arises the task of a multitude of different signal impulses from remote sources to a central reception to transmit direction. Such a central reception For example, a machine tool can with its Control. Such machines contain motors whose respective speed by means of the starting from the sources Hardware pulses should be controlled. Another possible one The purpose of such a receiving device is data on the receiving device side via a sensor at a time specified by the source. In addition to the pure transmission of the value of the hardware pulse also plays the runtime behavior of the transmission from the Source for the receiving device, i.e. the temporal organization tion and duration of the transmission, a crucial role. Only in this way can the full information content of the transmitting hardware pulse can be used on the receiver side be made.

It is known that conventional transmission methods for Fulfillment of these requirements for each source Provide management lines (Gelder, Erich: Integrated digital modules, 5th edition, Siemens shares Gesellschaft Berlin, Munich, 1984, page 462). So that known analog properties of these transmission lines The signal can be compensated for by additional  Electronics processed. The transmission that occurs However, dead times cannot be adequately taken into account the because they are used by the component scatter of the Filter (RC filter) and the spread of the line properties are dependent.

In the conventional transmission methods described above The following disadvantages must therefore be accepted. With increasing number of sources used, which with the Em are connected, the number of required transmission lines and thus costs and effort strong. It can also use high data transmission rates due to poorly considered transmission dead times lead to inaccuracies.

The invention is therefore based on the object of a method as well as an associated facility of the aforementioned Kind so that on the one hand, even when using many Sources connected to the receiving device that Number of transmission lines required and thus connected costs and expenses are kept as low as possible can and the accuracy of the transmission is improved, by performing a pulse delay correction and on this way transmission dead times are taken into account.

According to the invention, this object is achieved in that

• 1.1 several sources connected to one transmitter and through the same common transmission medium, a data bus, transmitted to the receiving device can,
• 1.2 each edge of a hardware pulse in the form of data value is transferred, which for the corresponding Edge of the hardware pulse significant information such as Source origin and type of edge, as code contains,
• 1.3 a transmission dead time is systematically recorded, the occurs when the data bus between the time of the  Occurrence of an edge change of a hardware pulse and the time at which the data bus for transmission the underlying flank change is released, is occupied
• 1.4 also the transmission dead time determined under 1.3 as coded information in those described under 1.2 Data value is included and part of the data will be worth
• 1.5 the data value within a specific transmission time that is known on the transmitter and receiver side and that of the performance and the used over transmission medium is specified to the receiving device tion is transmitted
• 1.6 on the receiver side by a pulse delay correction is performed by the receiver logic in the data transmission dead time and the specific value Transmission time summarized and from it the total dead time of the edge change of a hardware pulse,
• 1.7 the receiver logic the total dead time determined in this way a correction calculation to a constant, above the maximum possible delay value added and the edges encoded in the transmitted data value Change of a hardware pulse only after this time has elapsed evaluates.

Is a synchronous transmission that can be achieved using this method the hardware pulses with a constant time offset required, but an asynchronous transmission is sufficient accordingly, after a further advantageous training of the invention, the total determined on the receiver side dead time and thus the coded in the transmitted data value Edge change of a hardware pulse is evaluated immediately.

To such an advantageous transmission method according to the To implement the invention in a simple manner is the  Task solved by means of a device, characterized thereby records that

• 2.1 a source, for example a button, hardware pulses in Form of edge changes triggers and sent to a direction forwards,
• 2.2 a coding device that is part of the transmission direction is, edge change evaluates and the informa functions, such as the number of the source, during processing multiple sources, and type of flank change, increasing or falling edge, converted into a data value,
• 2.3 the transmitting device each have a counter for a stei leading edge and a counter for a falling edge for each source to determine transmission dead times includes
• 2.4 with the transmission device via a common data bus is connected to the receiving device and the coded Data value via this data bus from the transmitter is transmitted to the receiving device,
• 2.5 the receiving device contains a pulse decoder, the information contained in the transmitted data value recovered mations,
• 2.6 a correction element, which is also part of the Receiving device is one in the transmission of the Corrected transmission dead time,
• 2.7 a task-specific Ver to the receiving device is connected to the work facility desired the reference time of the source Action is executed.

The advantages achieved with the invention are in particular the fact that a transmission of many hardware pulses improved and ver. for example in industrial controls is approved because instead of a variety of own transfers a common data bus for multiple sources between multiple sources and a receiving device is used. Because of possible transmission dead times on the  Data bus can be systematically recorded and with the help of so determined values, a pulse transit time correction is carried out the accuracy of a transmission can be significant be improved.

Embodiments of the invention are in the drawing shown and are explained in more detail below. Here demonstrate:

Fig. 1 is a timing diagram of a synchronous code word transmission for a source with a double edge control,

Fig. 2 just the same timing diagram with asynchronous code word transmission for a source with double edge control and

Fig. 3 is a schematic diagram illustrating a device for realizing the invention.

In the illustration of FIG. 1 is a timing diagram for a code word transfer to a source of Doppelflankensteue tion is shown. For a hardware pulse P, consisting of rising edge F0 and falling edge F1, the data bus B is used to transmit the information of the hardware pulse in the form of data values D0 and D1. Both rising edge F0 and falling edge F1, which occur at times T0 and T1, are each identified by their own data values D0 and D1. First, the rising edge F0 of the hardware pulse P is considered. For this rising edge F0, a code word is first formed that contains the information number of the source (when processing multiple sources) and the type of edge change (rising edge or falling edge) . As a rule, however, this code word D0 cannot be applied directly to the data bus B when the rising edge F0 occurs, since the latter is usually still occupied by data from a previous transmission U. For this reason, dead times occur which are measured from the occurrence T0, T1 of an edge change F0 or F1 to the release of the data bus B. For the rising edge F0 Fig. 1 shows the associated Übertragungstotzeit by the value TZ0. In order to be able to carry out a pulse delay correction on the receiver side, the transmission dead times TZ0 and TZ1 are recorded systematically, ie continuously, by including their value in the associated data value D0 and D1. In relation to the rising edge F0 considered, this is the data value D0. At the time when a data value D0 or D1 is placed on the now free data bus B, it now contains the following information: number of the source, type of edge and in addition the associated measured transmission dead time TZ0 or TZ1. If there is a valid data value on data bus B, for rising edge F0 this is data value D0, the transmission time TÜ is determined by the performance of the transmission system and by the speed of the transmission medium, both on the transmitter side and on the side of the receiver is known transmitted over the data bus B to the receiving device. Looking again at the rising edge F0, Fig. 1 makes it clear that between the time of occurrence T0 of the rising edge F0 and the time of arrival of the associated data value D0 on the receiving device side, the measured time TG0, a specific total dead time ΔT0 passes. This total dead time, which occurs for each edge change F0 or F1, is measured, as can be seen from FIG. 1, according to the following equations:

ΔT0 = TZ0 + TÜ (1)

ΔT1 = TZ1 + TÜ (1 ′)

The same applies to the falling edge F1 of the hard warepulses P. Because of the busy data bus B because of a previous transmission U and the transmission of the data value D0 of the rising edge F0 occurs a transmission dead time TZ1 until data bus B becomes free and the  falling edge F1 representing data value D1 to the Data bus B can be laid. During the transfer of the Data value D1 in turn occurs due to the delay Transmission time TÜ on. On the recipient side, the falling edge F1 representing data value D1 after a Total dead time ΔT1 for the falling edge F1 at the time TG1 measured.

The receiver logic supplements the measured times TG0 for the rising edge F0 of the hardware pulse P and TG1 for the falling edge F1 of the hardware pulse P to a constant time value TK, which is above the maximum possible delay, and evaluates the coded data values D0 and D1 only after expiration this time TK out. These evaluation points are shown in FIG. 1 by TA0 for the rising edge F0 and TA1 for the falling edge F1 of the hardware pulse P. Fig. 1 thus makes it clear that the evaluation times TA0 and TA1 are calculated according to the following equations:

TA0 = TG0 + TK - (TZ0 + TÜ) (2)

TA1 = TG1 + TK - (TZ1 + TÜ) (2 ′)

TA0 = T0 + TK (3)

TA1 = T1 + TK (3 ′)

Fig. 1 thus shows that the underlying invention, the method allows a synchronous transfer of a hardware pulse P with a constant time offset TK. Based on this information, the exact event time T0 of a rising edge F0 and T1 of a falling edge F1 can be reconstructed on the receiving device side at any time according to the following equations:

T0 = TA0 - TK (4)

T1 = TA1 - TK (4 ′)

Also makes Figure 1 is clear that a hardware pulse P the pulse width TP can be directly from the Auswertezeitpunkten TA0 and TA1 F0 of the rising edge of the falling edge F1 directly calculated by the following equation.:

TP = T1 - T0 = TA1 - TA0 (5).

In the illustration of FIG. 2 is the same time chart as in Fig. 1 is shown, but with the difference that the receiver logic D0 and D1 and evaluates the data values directly after the total .DELTA.t0 .DELTA.T1 and not to a constant value as shown in Fig. 1 added. The result of this is that the evaluation times TA0 and TA1 from FIG. 2 correspond to the measured times TG0 of the data value D0 and TG1 of the data value D1 from FIG. 1. The following equations reflect this fact:

TA0 = TG0 (6)

TA1 = TG1 (6 ′)

On the basis of the designations from FIG. 2, the evaluation time of the data value associated with an edge change is calculated according to the following equations:

TA0 = T0 + TZ0 + TÜ = T0 + ΔT0 (7)

TA1 = T1 + TZ1 + TÜ = T1 + ΔT1 (7 ′)

The representation according to FIG. 2 thus represents an asynchronous transmission of hardware pulses P in the sense of the invention. Even in the case of such an asynchronous transmission according to FIG. 2, the time T0 or T1 of an edge change of the hardware pulse P can be determined using the evaluation times TA0 and TA1 reconstruct according to the following equations:

T0 = TA0 - ΔT0 = TA0 - ( TZ0 + TÜ ) (8)

T1 = TA1 - ΔT1 = TA1 - ( TZ1 + TÜ ) (8 ′)

If the pulse width of the hardware pulse P is to be reconstructed directly using the evaluation times TA0 and TA1 , as is possible using the method shown in FIG. 1, the original event times T0 must first be used using the modified method shown in FIG. 2 and T1 are determined in order to calculate the pulse width TP of a hardware pulse P therefrom. However, the slightly modified method according to FIG. 2 offers the advantage of a smaller time offset between the time of the event of the source T0 or T1 and the corresponding evaluation time TA0 or TA1 on the part of the receiving device.

In the illustration according to Fig. 3 is schematically shown an electro African device, such as a numerical controller, which tioniert radio by the process according to the invention. For the sake of clarity, only a single source Q, for example a push button, hardware pulses in the form of edge changes are triggered and forwarded to a transmitting device S. The transmitting device S contains a coding device C, which is an integral part of the transmitting device. An edge change is evaluated in the coding device C and according to the method described above, the information is converted into a data value, for example a double byte. When an edge change occurs, a counting device, which is also a component of the transmitting device S, is started. Since both edges of a hardware pulse are to be evaluated, two counters Z0 and Z1 must be available for each pulse source. For this reason, the transmitting device S contains the counters Z0 and Z1 as counting devices. If a rising edge occurs, the counter Z0 is started to measure the visualized in Fig. 1 and Fig. 2 Übertragungstotzeit TZ0. Accordingly, the counter Z1 is started when a falling edge occurs. Transmitting device S and the receiving device E are connected via a common data bus B. The data values representing the edge changes are transmitted from the transmitting device S to the receiving device E via this. The receiving device E in turn contains a pulse decoder PD, which recovers the information contained in the received data value. The pulse decoder PD is followed by a correction element K, which is also part of the receiving device E. In this corrective K turglied the information is evaluated in the underlying hardware pulse in accordance with the calculation rules of equations presented above (1) to (8) and in particular the corrected measured Übertragungstotzeit according to one of shown in FIG. 1 and FIG. 2 described method. A task-specific processing device VE is now connected to the receiving device E, be it a sensor or an actuator, on which the desired action related to the triggering time of the hardware pulse in the source Q is carried out.

A possible advantageous embodiment with or several sensors as task-specific processing Direction VE consists of a position-actual-value Acquisition on a shaft with constant orbital speed speed. To the transmitter S are a variety of Sources Q, for example buttons, connected. The broadcast device S and the receiving device E are local separated, so that all genes by means of the button (sources Q) hardware pulses were economically and technically very effective over the common data bus B from the transmitter S are transmitted to the receiving device E. With every gene The hardware pulse of a button is the point in time agrees, for which an actual position value on the receiver side the wave to be monitored is to be recorded. Meets on the A data value containing the information of the underlying button (source Q) and the associated button Transmission dead time includes, so this becomes exactly Time of the actual position value measured on the shaft. About the Correction element K can reproduce the time at which the  Button was pressed. With the help of this information the determines the exact position of the shaft at the time of Button actuation. That way, with With the help of the pulse delay correction despite the transmission dead time exact position of the wave at the time of pulse generation remotely located button (source Q) can be determined. The method is particularly effective if the counters Z0, Z1 on the side of the transmitting device S with the same constant Speed counts like the wave to be monitored turns. This allows the speed to be calculated directly basis for the route, d. H. the actual position value to be pulled.

An advantageous embodiment with an actuator as task-specific processing device VE provides a Speed control of one or more motors (actuator) using a pulse width control. Using a source Q, for example a hardware pulse generator with adjustable Pulse width, hardware pulses with variable pulse width are according to the methods described above as data values from the Transmitting device S via the common data bus B for Receiving device E directed. There are the data values evaluated by the method according to the invention and the Reconstructed pulse widths. The one with the help of the pulse duration corrected pulse widths are determined by the reception direction E to the motor (actuator) and from there Speed is changed using a pulse width control.

Claims (3)

1. A method for wired transmission of hardware pulses (P) from a source (Q) to a receiving device (E), characterized in that

• 1.1 several sources (Q) are connected to a transmitting device (S) and can be transmitted via the same common transmission medium, a data bus (B), to the receiving device (E),
• 1.2 each edge (F0, F1) of a hardware pulse (P) is transmitted in the form of a data value (D0, D1) which contains the information, such as source origin and type of edge (significant for the corresponding edge (F0, F1) of the hardware pulse (P) F0, F1) as a code,
• 1.3 a transmission dead time (TZ0, TZ1) is systematically recorded, which occurs when the data bus (B) between the time of the occurrence of an edge change (F0, F1) of a hardware pulse (P) and the time at which the data bus (B) for the transfer of the underlying edge change (F0, F1) is released, is occupied,
• 1.4 the transmission dead time (TZ0, TZ1) determined under 1.3 is also included as coded information in the data value (D0, D1) described under 1.2 and becomes part of the data value (D0, D1),
• 1.5 the data value (D0, D1) within a specific transmission time (TÜ), which is known on the transmitter (S) and receiver side (E) and which is determined by the performance and the transmission medium used, transmitted to the receiving device (E) becomes,
• 1.6 a pulse delay correction is carried out on the receiver side (E), in which the receiver logic combines the transmission dead time (TZ0, TZ1) and the specific transmission time (TÜ) contained in the data value (D0, D1) and from this the total dead time (ΔT0, ΔT1) of the edge change (F0, F1) of a hardware pulse (P),
• 1.7 the receiver logic supplements the total dead time (ΔT0, ΔT1) determined in this way in a correction calculation to a constant value (TK) above the maximum possible delay and the edge change (F0, F1) of a hardware pulse coded in the transmitted data value (D0, D1) (P) evaluates only after this time (TK).

2. The method according to claim 1, characterized in that the total dead time ( ΔT0 , ΔT1 ) determined on the receiver side (E) and thus the edge change ( F0 , F1 ) coded in the transmitted data value ( D0 , D1 ) of a hardware pulse ( P ) is evaluated immediately. 3. The method according to claim 1 or 2 with the device, characterized in that

• 3.1 a source (Q), for example a button, triggers hardware pulses (P) in the form of edge changes (F0, F1) and forwards them to a transmitting device (S),
• 3.2 a coding device (C), which is part of the transmission device (S), evaluates edge changes (F0, F1) and the information such as number of the source, when processing multiple sources, and type of edge change, rising or falling edge, in implements a data value,
• 3.3 the transmitting device (S) each contains a counter (Z0) for a rising edge (F0) and a counter (Z1) for a falling edge (F1) for each source for determining the transmission dead times (TZ0, TZ1),
• 3.4 the transmitting device (S) is connected to the receiving device (E) via a common data bus (B) and the coded data value (D0, D1) is transmitted from the transmitting device (S) to the receiving device (E) via this data bus (B),
• 3.5 the receiving device (E) contains a pulse decoder (PD) which recovers the information contained in the transmitted data value (D0, D1),
• 3.6 a correction element (K), which is also part of the receiving device (E), corrects a transmission dead time (TZ0, TZ1) that occurred during the transmission of the data value (D0, D1),
• 3.7 a task-specific processing device (VE) is connected to the receiving device (E), on which the desired action based on the time at which the source (Q) is dissolved is carried out.