Segmented control arrangement

Abstract

System arrangement for fault-tolerant and electromagnetically compatible control of a large number of execution units (AU), comprising: - a command unit (CU), wherein - the plurality of execution units (AE) into a plurality of serial subchains, each subchain having at least one execution unit (AE) along a first data line, segmented and each subchain having a line driver unit (LTE) upstream; and - the line driver units (LTE) are communicatively coupled to each other serially via a second data line, and the first line driver unit (LTE) connected in series is communicatively coupled to the command unit (CE) via the second data line, wherein the first data line is an electrical data line which always carries current, and the second data line is an optical data line.

Description

[0001] The present invention relates to a system arrangement for the fault-tolerant and electromagnetically compatible control of a plurality of execution units. Advantageously, the present invention allows execution units to be controlled in such a way that, among other things, both high common-mode robustness and high reliability are achieved, even with a large number of execution units. Furthermore, the present invention relates to a line driver unit for use in the proposed system arrangement and to a method for operating and / or manufacturing the proposed system arrangement. In addition, a computer program product with control commands is proposed that executes the method and / or operates the device.

[0002] WO 2017 / 162 323 A1 shows an efficient control arrangement and a control method in which sequentially arranged execution units are controlled by means of a command unit.

[0003] WO 2018 / 103 880 A1 shows a compact light-emitting diode arrangement which can be used generically, but is particularly advantageous for use in a vehicle due to its compact design.

[0004] WO 2017 / 153 026 A1 discloses a method for brightness compensation in at least one light-emitting diode.

[0005] DE 20 2013 103146 ​​U1 shows a device system with several devices for distributed arrangement along escape routes or traffic routes.

[0006] US 2014 / 333 207 A1 shows a protocol for exchanging status messages in a lighting system.

[0007] US 8,492,983 B1 discloses methods and systems for controlling lighting units.

[0008] DE 10 2016 125 290 A1 discloses method and device for the chained control and / or programming of several integrated circuits.

[0009] According to conventional methods, a multitude of ways are known to address control units connected in series. These include generic approaches, which can be disadvantageous in specific application scenarios, and highly specialized approaches that are no longer applicable in a generic manner. One well-known example is the so-called CAN bus, which was developed for wiring harnesses and is specifically designed to enable the networking of control units.

[0010] In general, the CAN protocol is significantly more complex than ISELED (registered trademark) and therefore more expensive. However, the most significant disadvantage of CAN and LIN is that, due to their bus architecture, they do not offer a natural (automatic) addressing method. Here, the address must be configured. With ISELED (execution units) and also with segmented ISELED (line driver unit and execution units), there is a physically predefined sequence, which provides the one possible way to automatically assign addresses.

[0011] In the prior art, various execution units are known, which typically operate as a so-called slave or client and receive commands from a superior instance, typically referred to as a master. The execution units then execute these commands. The prior art reveals different architectures or topologies for arranging such execution units and their control units.

[0012] However, the current state of the art presents a problem: different application scenarios demand different requirements, necessitating a careful consideration of whether to provide an energy-efficient method with higher susceptibility to interference, or a more energy-intensive but fault-resistant method. Furthermore, the dimensions of the intended deployment location for such an architecture must be taken into account. Some configurations are unsuitable for large-scale deployment and can therefore only be implemented on individual circuit boards. Other architectures, however, can be installed over large areas spanning several meters and consequently have entirely different requirements to meet than system configurations on individual circuit boards.

[0013] Furthermore, the state of the art addresses the problem of electromagnetic compatibility (EMC). Interference can occur, which can either be prevented from the outset or rectified subsequently. Additionally, interference can arise when individual components fail due to force or heat, leading to subsequent failures. This is particularly problematic when units are connected in series, with each unit receiving commands from the one preceding it. In daisy-chaining, for example, problems can occur if individual components fail and are not switched on. This isolates the downstream sub-chain from the communication flow, causing it to fail. Furthermore, very specific requirements apply to system configurations intended for installation in automobiles.A car is generally a high-priced product that the customer relies on constantly. Consequently, customers do not tolerate a high susceptibility to defects, and the components that need to be controlled are often safety-relevant. Responsibility to defects plays a crucial role here, as customers only want to contact customer service in exceptional circumstances, and the functionality of safety-critical units must be guaranteed.

[0014] It is therefore an object of the present invention to provide a system arrangement for controlling execution units which is fault-tolerant in the broadest sense and can also be provided with minimal technical effort. With regard to fault tolerance, particular emphasis is placed on electromagnetic compatibility and reliability. Furthermore, it is an object of the present invention to propose a line driver unit for use in the proposed system arrangement, as well as a method for providing and / or operating the proposed system arrangement. In addition, a computer program product with control commands is to be proposed which executes the method and / or operates the system arrangement.

[0015] The problem is solved by the features of the independent claims. Further advantageous embodiments are specified in the dependent claims.

[0016] Accordingly, a system arrangement for the fault-tolerant and electromagnetically compatible control of a plurality of execution units is proposed, comprising a command unit, wherein the plurality of execution units is segmented into a plurality of serial subchains, each subchain having at least one execution unit along a first data line, and each subchain is preceded by a line driver unit, and the line driver units are serially communicatively coupled to each other by means of a second data line, and the first line driver unit connected in series is communicatively coupled to the command unit by means of the second data line, wherein the first data line and / or the second data line is an optical data line.

[0017] The proposed invention offers, among other advantages, the ability to enable automatic address assignment, thereby increasing system-wide fault tolerance. Neither CAN nor LIN offers this advantage. According to the invention, the multitude of execution units, each segment preceded by only one line driver unit, results in a positive ratio between the number of execution units and the number of line driver units. This enables automatic addressing, unlike CAN / LIN, with maximum fault tolerance and minimal complexity due to the simple protocol. The serial arrangement allows for automatic addressing, meaning that each execution unit can be addressed using its own unique address.

[0018] The command unit sends commands as the master. A command includes, for example, an instruction (i.e., what to do, e.g., "set pulse width modulation PWM red channel"), and optionally a parameter (e.g., 255) and preferably an address. This address addresses one or more execution units. The execution units have a unique address, which is automatically derived from their physical location.

[0019] This makes it possible to include a process step that automatically assigns an address to each of the execution units, depending on their physical arrangement within the proposed system configuration. The physical arrangement can take into account the sub-chain in which each execution unit is located. This can include the line driver unit upstream of each execution unit.

[0020] The commands are typically distributed to all execution units by all line driver units. This eliminates the need for filtering or processing within the line driver units. The execution units then decide whether or not to execute the command based on their own address and the address contained in the command. Typically, they execute the command if they themselves are addressed by that address.

[0021] The present invention advantageously allows execution units to be controlled in such a way that both high common-mode stability and high reliability are achieved, even with a large number of execution units. It also enables the use of line drivers, which are, for example, optimal for optical or differential electrical physical media. Due to the segmentation, a small number of line driver units are required compared to the total number of execution units, thus allowing for higher current / power consumption and greater chip complexity than with the execution units themselves.

[0022] This proposal offers an alternative to bus solutions like CAN / LIN, which, among other things, solves the described problem of the lack of automatic addressing. Segmentation using line driver units, the possibility of passive switching, and optimization of the physical layer (common mode and electrically differential or optical) now resolve the issue of susceptibility to interference.

[0023] The proposed system arrangement is fault-tolerant, among other things, because the execution units are segmented and consequently arranged in subchains. This results in serial subchains, with the individual execution units connected one after the other. Therefore, if one execution unit fails, the disruption is limited to the subchain in which the failing unit is located. This offers an advantage over the prior art that instead of a large number of other series-connected execution units failing, only execution units within the same segment fail. This can also be addressed by simply switching through the execution units in the event of a failure.

[0024] The execution units are serially coupled, preferably bidirectionally. This allows the execution units to receive commands from the line driver unit and then execute them. A command can be an instruction, a reading, or a setting of a parameter. The execution units can be configured as LED units, controlling individual LEDs. LEDs are typically red, green, and blue, although a white LED may also be included. The execution units then execute the commands from the line driver unit and are also capable of providing feedback. For example, the line driver unit can instruct the execution unit to read a sensor, and the execution unit can then return the temperature value read from the sensor via bidirectional communication.

[0025] Since the invention involves several subchains or segments, a fault does not affect the entire subchain, as is the case in the prior art, nor does it affect all subchains, but only one (the affected) subchain. Instead, the reliability is increased by forming separate subchains that can be controlled individually. In a non-exhaustive list, the subchains contain at least one execution unit, with a line driver unit upstream of each subchain. Fault tolerance is also ensured by the fact that the line driver units pass through signals in the event of an inactive state. Passing through signals generally describes the forwarding of signals without processing them. Consequently, no logic is implemented or processing steps are carried out within the failed element.Rather, a signal present at an input is output without any processing.

[0026] Electromagnetic compatibility when controlling a large number of execution units can be achieved, among other things, by always using differential modulation; that is, the line is actively driven even when no command is being transmitted. This eliminates the steep edge that occurs when the line driver is switched on and off. According to the invention, it is possible to implement the proposed topology such that at least one cable connection (optically or electrically differential) is established between the line driver units. Consequently, the data line is not implemented on a printed circuit board as conventionally, but rather the individual subchains are arranged on a printed circuit board, and the resulting printed circuit boards can be communicatively coupled via a cable connection (optically or electrically differential) through the respective line driver unit.Therefore, it is particularly advantageous that the number of sub-chains scales, since any number of line driver units can be connected in series and a sub-chain of execution units is communicatively arranged or coupled to each line driver unit.

[0027] Generally, the number of execution units or line driver units to be operated is limited by the address space, i.e., the number of units that can be addressed. Since the address space can be chosen arbitrarily, the number of units to be installed also scales accordingly.

[0028] The proposed system configuration includes a command unit that ultimately controls the individual execution units. This control is typically not direct, but rather occurs via the line driver units. The command unit generates commands and transmits them to the execution units via the respective line driver units, and also receives parameters and values ​​from the execution units via the line driver units. Thus, the command unit represents a superior instance to the line driver units and can therefore be referred to as the master unit. In this configuration, the line driver units behave as slave units or client units.Since the line driver units are positioned upstream of the subchains, i.e., the execution units, and the line driver units transmit the commands to the respective subchains, the line driver units behave like master units in this respect vis-à-vis the execution units. The execution units then assume the role of the slave unit or client unit.

[0029] For example, the proposed system arrangement is a chain of LEDs. The command unit outputs a specific pattern, which is to be implemented by the individual LEDs. To this end, the command unit controls the individual line driver units, which then forward the command to the respective sub-chain. The line driver units can not only forward the command but also adapt it independently. The individual execution units ultimately implement the command and, for example, control individual LEDs. These could be red, green, and blue LEDs, with a white LED optionally included. The execution units can also be other actuators such as motors, matrix LEDs, sensors, temperature sensors, light sensors, or pushbuttons.

[0030] The first data line is the one that forms subchains. This first data line connects the individual execution units and links this chain of execution units to exactly one line driver unit. Thus, the data line initially comprises a line driver unit, to which one execution unit is connected. Optionally, further execution units can be connected serially to this execution unit. There is no restriction on the number of execution units; only the underlying address space is selected accordingly. The address space does not need to be fully utilized; rather, it merely represents an upper limit for the number of execution units to be installed.

[0031] The second data line connects the line driver units to each other serially and preferably bidirectionally. The command unit is the first unit connected to the second data line, followed by at least one line driver unit.

[0032] Since each sub-chain has its own data line, the first data line can be considered a data line of the first type. Generally, there are as many first data lines as there are sub-chains. For example, if there are three sub-chains, exactly three line driver units are installed, forming three sub-chains, each containing a data line of the first type. Consequently, in this case, there are exactly three first data lines. The distinction between first and second data lines allows the first data lines to be designed differently from the second data line, which is typically only present once. Thus, the first data line can be arranged on a circuit board, while the second data line can, for example, be a cable.This results in a particularly advantageous, flexible design that is especially suited to the application scenario in the automotive industry.

[0033] According to one aspect of the present invention, the line driver unit upstream of a sub-chain acts as a master unit for the at least one execution unit of that sub-chain, and the at least one execution unit acts as a slave unit with respect to this line driver unit. This has the advantage that the execution units can receive commands from the line driver unit, and the commands are then passed through and executed by the execution units. Thus, the line driver unit provides a command that is routed through the sub-chain and executed and passed on by each execution unit. Furthermore, it is also possible to address a single execution unit by means of an address, so that the corresponding command is addressed by the line driver unit to this specific execution unit through the chain.Once the command has been executed, it is also possible to transmit a result from the respective execution unit back to the preceding execution unit and then provide the final result to the line driver unit. In this case, bidirectional communication within the subchain is advantageous. The command is advantageously issued by the command unit and typically passed on unchanged to the execution units via the line driver units.

[0034] According to a further aspect of the present invention, the command unit acts as the master unit for the line driver units, and the line driver units act as slave units with respect to the command unit. This has the advantage that a single command or a sequence of commands can be created by the command unit and transmitted to the line driver units. The line driver units thus receive this command or these commands and forward them, as necessary, unchanged or adapted, to the execution units. Here, too, it is possible for the line driver units to be addressed individually by means of an address and, if necessary, also to output feedback to the command unit.

[0035] According to a further aspect of the present invention, the first data line and / or the second data line are configured bidirectionally. This has the advantage that commands or signals are transmitted in both directions, and consequently, both the execution units can send return values ​​to the line driver units, and the line driver units can send signals to the command unit. In particular, the individual units can communicate with each other. Preferably, both data lines are configured bidirectionally, although it is also possible for only the first data line or the second data line to be bidirectional. Since several data lines of the first type are present, it is also possible for the individual first data lines to be configured differently. Typically, however, all first data lines are configured identically.

[0036] According to a further aspect of the present invention, signals on the second data line are modulated with a larger amplitude than signals on the first data line. This has the advantage that greater distances can be covered without errors using the second data line. A higher amplitude ensures that the distinction between zero and one is clearer, and thus the signal modulation is less prone to errors. It is therefore possible to implement the first data line on a printed circuit board and the second data line using a cable, which is then also modulated with a correspondingly larger amplitude due to the greater distance.

[0037] According to a further aspect of the present invention, signals on the second data line are modulated with an amplitude 10 times greater than signals on the first data line. This has the advantage that, surprisingly, this value is particularly beneficial, allowing the signals on the first data line to be modulated very efficiently, while the signals on the second data line, although modulated less efficiently, are significantly more error-resistant. Surprisingly, it was discovered according to the invention that precisely the proposed value is particularly well suited to determining the ratio of the amplitude of the second data line to that of the first data line.

[0038] According to a further aspect of the present invention, the first data line and / or the second data line is an optical data line. This has the advantage that several options can be offered, which in turn can be selected depending on the application scenario. According to the invention, an electrical data line is preferably implemented.

[0039] According to a further aspect of the present invention, the first data line or the second data line is an electrical data line that always carries current. This has the advantage that differential transmission is always possible, and consequently, there are no disadvantages associated with a particularly steep edge while the current is applied. Rather, a current is always present, and transient response is prevented. Thus, the proposed method is also insensitive to electromagnetic interference. Furthermore, it is advantageous to choose such a configuration because a cable connection can be implemented that must bridge greater distances of several meters.

[0040] According to a further aspect of the present invention, each line driver unit, together with a sub-chain, is arranged on its own printed circuit board. This offers the advantage that the line driver units, together with the execution units and the respective first data line, can be optimized for short distances and consequently can also be arranged on a single printed circuit board. This also reduces the susceptibility to errors, since the execution units are segmented, and individual sub-chains are addressed separately by means of printed circuit boards.

[0041] According to a further aspect of the present invention, the line driver units are each configured such that signals on the second data line are passed through the respective line driver unit when it is inactive. This offers the advantage that if one line driver unit fails, the other line driver units connected in series can still receive commands and send signals back. Thus, the defective line driver unit is simply ignored, and the corresponding signals are passively passed through. Consequently, no signal processing takes place in the defective line driver unit, and this line driver unit also does not interrupt the rest of the chain. Therefore, it is advantageous that only one sub-chain of several sub-chains fails when a line driver unit fails.

[0042] According to a further aspect of the present invention, the implementing units are each configured as a light-emitting diode (LED), motor, sensor, temperature sensor, light sensor, push button, or switch. This has the advantage that different implementing units can be provided, with an LED being particularly preferred according to the invention. The LED can, in turn, comprise individual units that emit red, green, or blue light. Generally, however, it is also possible to mix the individual implementing units, such that, for example, LEDs are present and sensors are also included within the same chain. Furthermore, one sub-chain can be formed from LEDs and another sub-chain from sensors. Preferably, however, all implementing units are configured identically.

[0043] According to a further aspect of the present invention, the execution units are configured to provide at least one status piece of information to the line driver unit. This has the advantage that the line driver unit can instruct that a specific value be read, and this command is then forwarded through the subchain to the addressed execution unit, which in turn returns the requested value via the other execution units. Bidirectional communication is particularly advantageous in this context.

[0044] The task is also solved by a line driver unit for use in the proposed system arrangement.

[0045] The problem is also solved by a method for fault-tolerant and electromagnetically compatible control of a plurality of execution units, comprising a provision of a command unit, wherein the plurality of execution units are segmented into a plurality of serial subchains, each subchain having at least one execution unit along a first data line, and a line driver unit is placed upstream of each subchain, and the line driver units are communicatively coupled to each other serially by means of a second data line, and the first line driver unit connected in series is communicatively coupled to the command unit by means of the second data line, wherein the first data line and / or the second data line is an optical data line.

[0046] The task can also be solved by a computer program product with control commands that execute the procedure or operate the proposed system arrangement.

[0047] According to the invention, it is particularly advantageous that the system arrangement provides structural features that functionally correspond to the process steps. Furthermore, process steps are proposed that can also be structurally replicated by the system arrangement with respect to their corresponding functionality. Thus, the method serves to operate the system arrangement, and the system arrangement can execute the proposed method.

[0048] Further advantageous features are explained in more detail with reference to the accompanying figures. They show: Fig. 1: a sub-chain comprising a microcontroller and several series-connected LED units according to the state of the art; Fig. 2A, Fig. 2B: a modulation of data as an application example of the present invention; Fig. 3: the proposed system arrangement in a block diagram relating to an aspect of the present invention; and Fig. 4: a flowchart according to the proposed method for fault-tolerant and electromagnetically compatible control of a plurality of execution units according to one aspect of the present invention.

[0049] Fig. Figure 1 shows a microcontroller on the left, which acts, for example, as a command unit. In addition, several execution units are arranged via bidirectional communication; these are implemented here as LED controllers. This is indicated by the reference symbol MLED CTRL. The current state of the art has the disadvantage in some application scenarios that if one controller fails, all other controllers connected in series also fail, as communication is interrupted.

[0050] Fig. Figure 1 shows a possible configuration of a system or communication arrangement according to the prior art. The command unit BE, which is connected to three control units, is visible on the left. Since the three control units are connected in series, the command unit is directly connected to one control unit and indirectly connected to the other. The control units can be so-called multi-LED controllers. This is shown in the present Fig. Figure 1 is shown as MLED CTRL. The uniform reference symbol is intended to clarify that the control units are typically designed identically. As can be seen, the LEDs are RGB (red, green, blue) LEDs. These are configured to set a specific color value by means of a mixing ratio of the individual LED units. Furthermore, the figure shows that additional components may be required. For example, it may be necessary to provide a power supply. However, it is also possible to provide these components, such as the power supply, externally and simply connect them.

[0051] The data line is present as a plurality of data line segments, which are shown as bidirectional arrows SIO1, SIO2. Control units can also be referred to as execution units. The MLED controller can also be referred to as the ISELED controller, as it can be used as an execution unit according to the invention.

[0052] Fig. Figure 2A shows data modulation, where the data lines are differentially modulated only during the active phase when commands are being transmitted. During the inactive phase, when no commands are being transmitted, the current on both lines is switched off, and both lines "fall" to a non-differential potential, which is typically assigned by termination. The transition from the active phase (differential, with high current consumption) to the inactive phase (non-differential, no current consumption) is marked by a steep edge. The vertical lines also indicate a clock signal, which is used to extract semantic information from the signal. Preferably, the signal is read within the clock cycle if the amplitude is at its maximum, in order to achieve error robustness. The data shown could be synchronization data on the left and a command on the right.

[0053] In general, the dimensions and content of the Fig. 2A and Fig. Figure 2B is merely an example and a schematic representation. Other modifications may also exist.

[0054] Fig. Figure 2A exhibits a disadvantage in the prior art, namely the steep slope on the left side, which is not electromagnetically compatible. Therefore, such a modulation is not very suitable for a cable connection. This modulation is suitable for a printed circuit board, which is why, according to the invention, transmission can only be performed on the first data line in this manner. This is because the connection is short and shielding is possible.

[0055] Fig. 2B displays a superimposed signal and therefore shows two characteristic curves. Unlike 2A, the data line is always actively driven. The command is transmitted using a sequence of bits that are differentially modulated, as in... Fig. 2A. In contrast to Fig. 2A: After the command is transmitted, the data lines are not switched off and continue to send a differential idle pattern. This is an aspect of data modulation that can also be used according to the invention. A particular advantage is that, according to the invention, without any adjustment of the transmitter, not only is sampling at such unfavorable times—i.e., when the signal strength is close to the threshold—avoided on the receiver side, but sampling also takes place at maximum amplitude. This guarantees a sufficient distance between the signal strength and the threshold at a measurement point, i.e., the sampling point. The sampling point is positioned within a bit width, which determines the time interval within which the respective bit to be transmitted is encoded. Thus, the sampling point must always be selected within this bit width and reads out a bit assignment.The individual bit widths that divide the serial bit data stream into individual bits are typically equidistant in time. An idle pattern is also referred to as an idle pattern.

[0056] In typical sampling scenarios, the sampling point can be located at the midpoint of a bit width. For example, the signal strength increases at the beginning of the bit width when transitioning from an encoded zero to an encoded one, reaches its maximum approximately in the middle of the bit width, and then decreases if a zero is to be encoded subsequently. Therefore, the midpoint of a bit width can be chosen as a reference point for a suitable sampling time.

[0057] Fig. Figure 3 shows the proposed system configuration, where the command unit BE is a microcontroller. This command unit BE is communicatively coupled to a plurality of line driver units LTE. The command unit BE is connected to the serially connected line driver units LTE via the second data line. Each line driver unit LTE has three interfaces for this purpose: interfaces A, B, and C. As shown, a line driver unit LTE communicates with a subchain of execution units AE. These execution units AE are also connected in series and communicate via the first data line.

[0058] As also shown, there are several subchains, each comprising an LTE line driver unit and at least one AE execution unit. Therefore, there are also several type I data lines, although only three subchains, i.e., three type I data lines, are shown.

[0059] The proposed system scales, as indicated by the points drawn between the second and third subchains. These points illustrate that an indefinite number of subchains are possible. The number is limited only by the address space. (See bottom right of the diagram.) Fig. Figure 3 shows that different numbers of execution units (AE) can be provided, which is also indicated by dots. Here too, the address space is decisive for the number of execution units (AE).

[0060] In the present case Fig. Figure 3 shows the first data line horizontally and the second data line vertically. The second data line also refers to the connection between the command unit BE and the multiple line driver units LTE. The horizontal subchains can each be arranged on a printed circuit board, while a cable connection can be implemented between the vertical connections. This allows for vertical transmission over distances of several meters. The terms "vertical" and "horizontal" refer only to the illustration, and those skilled in the art will recognize that the actual implementation will vary depending on requirements.

[0061] Fig.Figure 4 shows in a schematic implementation diagram a method for the fault-tolerant and electromagnetically compatible control of a plurality of execution units AE, comprising a provision 100 of a command unit BE, wherein the plurality of execution units AE are segmented into a plurality of serial subchains, each subchain having at least one execution unit AE along a first data line 101, and each subchain is preceded by a line driver unit LTE 102, and the line driver units LTE are serially communicatively coupled to each other by means of a second data line 103, and the first series-connected line driver unit LTE is communicatively coupled to the command unit BE by means of the second data line 104.

[0062] The person skilled in the art recognizes that the described process steps can be carried out iteratively and / or in a different order. Furthermore, individual process steps can have sub-steps.

Claims

[1] System arrangement for fault-tolerant and electromagnetically compatible control of a plurality of execution units (AU), comprising: - a command unit (CU), wherein - the multitude of execution units (AE) into a plurality of serial subchains, each subchain having at least one execution unit (AE) along a first data line, segmented and each subchain having a line driver unit (LTE) upstream; and - the line driver units (LTE) are communicatively coupled to each other in series via a second data line, and the first line driver unit (LTE) connected in series is communicatively coupled to the command unit (CE) via the second data line, wherein the first data line is an electrical data line which always carries current, and the second data line is an optical data line. [2] System arrangement according to claim 1,characterized by , that the line driver unit (LTE) upstream of a sub-chain acts as the master unit for the at least one execution unit (AE) of this sub-chain and the at least one execution unit (AE) acts as the slave unit with respect to this line driver unit (LTE). [3] System arrangement according to claim 1 or 2, characterized by , that the command unit (CE) acts as the master unit for the line driver units (LTE) and the line driver units (LTE) act as the slave unit with respect to the command unit (CE). [4] System arrangement according to one of the preceding claims, characterized by that the first data line and / or the second data line is bidirectional. [5] System arrangement according to one of the preceding claims, characterized by , that each line driver unit (LTE) together with a subchain is arranged on its own circuit board. [6] System arrangement according to one of the preceding claims, characterized by , that the line driver units (LTE) are each designed in such a way that signals on the second data line are passed through the respective line driver unit (LTE) when it is inactive. [7] System arrangement according to one of the preceding claims, characterized by that the execution units (AE) are each designed as a light-emitting diode, motor, sensor, temperature sensor, light sensor, push button or switch. [8] System arrangement according to one of the preceding claims, characterized by that the execution units (AE) are configured to provide at least one status information to the line driver units (LTE). [9] Line driver unit (LTE) for use in a system arrangement according to any one of claims 1 to 8. [10] Method for fault-tolerant and electromagnetically compatible control of a plurality of execution units (AE), comprising: - providing (100) a command unit (CE), wherein - the plurality of execution units (AE) are segmented into a plurality of serial subchains, each subchain having at least one execution unit (AE) along a first data line (101) and each subchain is preceded by a line driver unit (LTE) (102); and - the line driver units (LTE) are communicatively coupled to each other serially via a second data line (103) and the first line driver unit (LTE) connected in series is communicatively coupled to the command unit (BE) via the second data line (104), wherein the first data line is an electrical data line which always carries current, and the second data line is an optical data line. [11] Computer program product with control commands which execute the method according to claim 10 when executed on a computer.

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