DE2365871A1 - DATA TRANSFER SYSTEM - Google Patents

Description

PATENT ADVOCATES A. GRÜNECKER

W. STQCKMAIR

CW-ING. AaEICALTECH)

K. SCHUMANN

Dft R £ R NAT. · CHPL-PHYS

P. H. JAKOB

QPL-ING.

G. BEZOLD

Dft REfI NAT. · DIPL-CHBM

• JOENSON SERVICE COMPANY 507 East Michigan Street Milwaukee, Wisconsin ^ 201 _{8 MUNICH 22}

U. S. A MAXIMILIANSTRASSE 43

i. April 1976 -j 7549 II-52 / Sr

Data transmission system

The invention relates to a data transmission system in which several remote stations are connected via a ring transmission link are connected to a central control station which has a generator for a frame code signal with which one continuous sequence of temporally separated, temporally spaced data frames can be generated, wherein Each of the remote stations a variety of bit-coded Receives signals, can send them to a subsequent station and has several consumers that are in the form of point modules designated functional groups are divided.

Such a data transmission system is used, for example, to monitor and control environmental conditions. Such data transmission systems were developed with systems hardwired together, some of which are the various controls in multiplex operation, such as this, for example, in the

609835/0962

TELEPHONE (ΟΒβ) 22 2S 62 TELEX O5-2S380 TELEGRAMS MONAP

U.S. Patents 5,500,759 and 3,396,379. Computer scanning systems have also been developed to provide high speed periodic scanning of various input signals. The TJS-PS 3,369,904 shows a more advanced data transmission system, in which a central computer generates a sequence of coded transmission data with time gaps _s serially given to remote stations. However, such systems have not been designed so that a general data transmission could be made with them, as is required for the continuous monitoring and control of environmental systems, the electrical signaling devices such as analog devices, switch arrangements and on and off devices with switch positions and operating states monitoring facilities and the like.

The object of the invention is to provide a new data transmission system to create, with which in a simple manner and without complex synchronization devices a large number of remote Is to monitor and control stations.

In the case of a data transmission system of the type mentioned, this is. Object according to the invention is achieved in that at each remote station one responsive to the bits of each frame Frame processing means is provided that each of the Frame has at least three data words that start with a frame state- and address location with bits for the initial frame state and bits for subsequent station addresses, a second multi-bit data word with acknowledgment bits and subsequent bits for several point module addresses for the selection of remote monitoring devices and a 'third, Multiple bit data word with multiple command bits and operation data bits for performing selected operations

609835/0962

of consumers within a point module.

The data transmission system according to the invention is therefore a system with serial data transmission that programmed one Computer used to generate and transmit general data to operate associated terminals. Of the Computer to carry out a sequence of instructions stored in it and to modify those instructions as it is specified by these commands is part of a control station for the transmission loop that is in series over a cable with a "multitude of in the transmission loop lying distant stations is connected. The latter include the controlled loads and various input-output devices that receive and transmit of information to and from the transmission loop. The control section for the transmission loop generates time-spaced signal frames, the no start and stop signals and no temporary ones either Require synchronization, and receive or send the encoded information to or from the remote stations. The remote stations can be enlarged or reduced in terms of their peripheral devices, like this one within the limits of the system is possible.

In detail, the control station generates the message or Information frame as a sequence of frames, each in time is spaced from the following frame. Each frame has a plurality of serial information bits with pus-free periods between the frames. The bits within each frame are functional too Groups combined to at least one address group or word, a command group or word and a data group and station status group or word. To a feature of the invention is a remote station with?

6098 35/0962

one or more functional point modules provided with similar devices and response devices, such as devices for monitoring switch divisions, for Start-stop control Uodglo with the transmission loop below Control of a data processing device or program logic Coupling su ο The data transmission with the point modules is carried out with a logic module processing the data frames 9 which is connected to a common branch line where the data frames have a point address group or word following a first station address word. the According to a further feature of the Invention wired to an authorization precedence in the Define treatment of requirements of the various point modules =

According to a special feature of the invention, three consecutive starting bits of the first word encode the Framework as a general, a specific or a general ~ frames assigned to common stations. The following bits indicate the station address. Each remote station can use Participate in the data transfer using the first type of frame. However, only one addressed station can do this with the second Frame type ο The third frame type transmits a general command and / or the data to all remote stations.

The second word has initial station acknowledgment bits for confirming an addressed frame or for confirming the completion of an available frame with subsequent bits which indicate the point module address.

The third word of the frame has starting command bits, the can be used to inform the control station for the transmission loop of an error in order to access an appropriate Addressing the frame »The third word ** is also

ζ / Π 3 82

Status bits for recording the operating status of a remote station, such as a parity error or failure a local supply source and a request for a frame. The requirement of a point module is only eliminated by actuation of an interrupter device by a corresponding command containing frame. All interrupter devices for the point modules are only triggered when a special frame is received that has a command to trigger and that from the control station only then is generated when an error-free frame is received. The point module thus fills another available frame in order to effect a suitable data transfer.

Each remote station has a voltage monitoring system to bypass this remote station if one Local supply source required for data transmission fails. The remote stations have monitoring devices that check the interval between frames and continuously generate frames with a single address, which the control station detects as an interruption in the transmission loop.

The address selection device and the various interlock control devices are designed so that the control station Detects problems encountered in the operation of the transmission loop and notices. A noise or the like. resulting parity error can be due to the stored in the computer A program for rejecting such erroneous information and retrying the operation with the error to lead. If the system corrects itself, the error is not displayed. However, if the error is repeated in one rapid result, the reduced operational readiness of the system is displayed to the operator immediately. Step each

809835/0962

but a permanent error, such as a component or supply voltage error, becomes the problem in question indicative information generated to initiate appropriate corrective action.

Each of the Übertraguagsschleifensysteine may further includes a battery powered real time clock may be provided with which the _s ^ Arbeitsi continued else the system in the event of a fault in the power supply. Is.

According to another feature of the invention is a portable Operating device of standardized design for a group of transmission loops of the system under control by the assigned control station provided. The control unit is in series with the selected transmission loop in this to insert. The control unit has a special unique address for the group of transmission loop systems, in that it can be used. The control unit speaks to a group of point module addresses under the control of the stored program in the control station of the transmission loop in which it is switched on. The data transfer begins either as a result of changes at a remote station or as a result of a specific request from the operator on the control unit. The control unit has a display device for operating states and measured values either in the form of visually perceptible, audible or similar output signals and enables the input of data and parameters to be sent out by the operator to and from the various other remote stations to be sent by the Control Unit, including modifications to the operation of the Control Unit. The operator thus has means for requesting and displaying monitored measured values, alarm thresholds or the like. The operator can also control functions such as

609835 / 09S2

Variations or changes in the manipulated variable., Starting and Stopping certain structural units, such as motors, and the like. - An auxiliary acoustic transmission is preferably also under the control of the operator-) person with an automatic audible alarm signal upon occurrence of alarm conditions at any particular one Station provided. The control panel of the control unit has indicator lights or the like. on, the three switching states, namely on, off or blinking, have to be a normal, a confirmed abnormal and an unconfirmed abnormal Condition to be specified. The confirmation is made by a switch on the control panel. Numerical display devices for dates and / or times with the simultaneous specification of the respective data type are also provided.

Manually operated address switches are used to enter addresses into the system for dialing specific remote locations Stations, point modules and devices are provided within a point module. Puncture switches allow input a numeric code in an information frame for special operations, such as display, parameter input od4jl. Switches for entering values are also provided for direct entry of four-digit decimal and to enable digital information. There is also a display device associated with the numeric display device to indicate whether the particular condition displayed or the point module is in a normal operating state or the alarm operating state.

The control unit starts the data transfer with the Control station via any of three control switches which include a transmit or interrupt switch, the requests an available frame, which can be accessed via the operating

609835/0982

device is filled up by actuating address and puncture switches "The actuation of the switch" causes the address of the operating device to be introduced in an available frame, which is sent to the control station, which in turn generates a following group of r Kahiaen, which the reading input values to the data switches. the operation of an operating switch causes the switching of the flashing indicator lamps in its oN state and if _s used, the disconnection of an acoustic Arlarmzeichens.

In addition, the control unit has a special and dem EIA standard RS-232-C socket and an internal, optionally used circuit module within the Control device in order to enable the connection with other devices that comply with this standard. This is for the operation of special devices, such as teleprinters, slide projectors or the like. desired that as Additional device to the control device can be used. In this way, the operating device in the new data transmission system be used as the actual operating unit, which enables data transmission with the control station and the remote stations and can act as a single support unit for each one of a multitude of transmission ^ loop systems are used when in a plurality of transmission loops is used in the data transmission system.

It has been found that the new data transmission system is extremely versatile and especially for heating, Ventilation and air conditioning systems or the like. Process controls used where the remote station usually has selected, interrelated devices that

60983S / 09S2

functional in certain types of input and output devices can be combined in groups «

The invention is illustrated with reference to in the drawing Exemplary embodiments explained in more detail »Show in detail?

Pig. 1 shows a block diagram of a general data transmission system which comprises a large number of similar transmission loop systems connected to one another, which are connected to a central computer center, _{see FIG}

FIG. 2 schematically shows a remote station of the type shown in FIG Type and its basic components,

Fig. 3 is a Barstellung the module organization of the information sr mimic s _s

Fig. 4- a control unit with the various input-output elements to operate the control unit,

5 shows a point module for monitoring and controlling a Motors and

6 shows a unit generating and processing an information frame.

In the data transmission system shown in Fig. 1, a main computer center 1 is provided, which has a computer unit which can optionally be time-multiplexed with a variety of transmission loop systems 3 _S 4 and % as well as with other peripheral devices, e.g. a telex 6 od {% 1. can be connected. The computer center 1 controls a large number of different devices and systems in this way by means of a suitable follow-up or scanning system. Each of the remote loop systems 3 ″ to 5 is designed as a closed transmission loop, whereby the transmission loop 3 is shown in detail as a block diagram. The transmission loop 3 has a control

808835/0 95

Set 7 to ₉ which causes a programmed mode of operation and a large number of identical remote stations 8 as well as a specially designed remote control unit station 9, all of which are in a single loop with the control station 7 with the aid of a common transmission cable

10 are switched =. The control unit 7 includes a computer 7A with a stored program to _see the effects of internally stored instructions to perform and can make particular, the modification of these stored commands ,, as this is defined by the commands and programming the circuit. " The computer 7A can also be provided with suitable input and output connections ₂ to manually control the operation, or it may be connected to the central computer 2 be connected to operate with this "The computer and corresponding ^ö ignal processing means may be used as be any known hardware devices _s that are such that the illustration and description of certain circuit details and would complicate devices of the present description unnecessarily, so omitted here stand in the multiplex and the binary signal processing for disposal.

The control station 7 has a device for serial transmission of time-spaced information or data frames

11 and 12 over the cable 10 to _9, each of which is divided into a sequence of binary signal bits ^v , denoted by the conventional symbols as logic zero or 1, in order to enable data transmission between the control parts 7 and the various remote stations 8 " and 9. A preferred new structure of an information or data frame 11 or 12 is explained in detail later in connection with FIG

S09835 / 0982

each frame has an optional coupling to each of the remote ones Stations 8 to 9 for information and data transmission to or from these stations and the control station 7 makes. The control point 7 is therefore the creation point of each frame and the final one Destination of each frame and automatically evaluates any information received from a remote station is received, and also checks that each information frame has caused and controls an appropriate response finally the activation of a switched-on remote Station for a subsequent transmission. In addition, to allow data transfer between the various Providing stations can be a visual or other transmission that can be perceived with the human senses. see the stations or from the stations to the control station by using suitable interface devices, such as a teleprinter, at the control station and / or a or more of the remote stations 8 to 9 can be provided.

Although every two-wire system is used to transfer the data in serial form can be used between the individual elements is a coaxial cable shown in Fig. 6, for example 10 particularly suitable to the desired transmission speed to be achieved via the desired transmission paths that are required for heating, ventilation and air conditioning systems are. 1 to 31 stations can be separated from each other by distances of approx. 600 m. without having to use a repeater.

Each sub-number of bits or positions indicating a data frame 11 is considered a sequence of immediate adjacent, equal time gaps are transmitted, with each of the frames passing through a noticeable time interval is separated from the other, like this one schematically

60983 5/0962

In Fig. 1 by the distance shown between the frames 11 mna 12 is ο Me frames are asynchronous from the Control point 7 generated according to the stored program , but under all circumstances at a minimum speed so that the distance between successive Frame is a chosen maximum interval.

The data frames 11 and 12 are sent in this way over the cable 10 to the first remote station 8, which the Bits are serially analyzed and sent through the remote station to the next following remote station »

According to a preferred embodiment, each of the remote stations is generally structured as shown in FIG. 2. The remote station 8 has a logic circuit 13 which processes the data frame _. which has an input terminal 14 connected to cable 10 for receiving the frame bits. The logic circuit 13 analyzes each bit and sends 6 3 either modified or unmodified, depending on the state of the bit and its relationship to the overall program. In the loop system, each data frame is processed simultaneously by each of the remote stations _s with one bit delay per station, with each station naturally processing or analyzing a different bit of the entire data frame »

In this way, the analyzed bit is sent out via an output 15 in order to be transmitted to the next following remote station. During the processing of an information frame, the logic circuit 13 determines whether it is intended for this station or is otherwise available for the station and, if necessary, causes

SQ9835 / 0962

the necessary. Functions within the station »

Each remote station 8 also has a plurality of functional point modules or devices 16 to 18, which are generally represented by the blocks labeled "PM" in FIG shown are j as well as a particular module 16A, the one Telegraph 16B controls the three point modules 16 to 18 are, as apparently shown, with a common Rail line and the logic circuit 13 via a common Input rail 19 and a common return rail 20 connected »The appropriate frame» signals are given simultaneously to each of the modules, one of which is activated and the return information the common return rail 20 to the logic circuit 13 there so that it is included in data frame 11 «

'' The point modules can take over the coupling between functionally similar devices with the transmission loop. For example, the point module 1 "6 can make the connection and adaptation between a switch sensor 21, which in its switched-on state monitors the switching state of one or more contact sets, and give the respective information to the control station 7. The point module is a connection element to a suitable one The third module 18 is shown as a start-stop control with the operating status detection, which has a device for controlling the stopping and starting of an engine, as well as for generating the operating state of the Other typical controllers may be indicative of motor feedback signal _a A particularly operationally reliable engine control module is shown in FIG. 5., in the

809835/0982

Heating, ₂ ventilation and air conditioning systems are provided _? include an analog signal selector module or an analog. Digital converter module and interface devices for peripheral devices 5 which meet the EIA standard BS-2J2-C for connecting sound peripheral devices, such as ζ, B ₀ the teleprinter 16B for data transmission between local remote stations with the control point The devices associated with the modules are such that in some cases information can be obtained from the data frames 11 or 12 which constitute a command for the point module to perform a particular operation in accordance with selected data sent to the module terminate or carry out or send information back to the control station 7 = since more than one of the point modules 16 Ms 18 one. Can request frames and therefore generates a control signal on the common rail line 20, the point modules 16 to 18 have a locking line 23aj in order to effect a continuous physical through-connection of the electrical connections between the point modules and the common rail line and thus a priority control o

In addition, each remote station has 8 a power source and a monitoring device 24, the ₉ to do with the various point modules 16 to 18 _seconds to provide a continuous monitoring of the various power sources of the logic circuit and the working loads or hardware facilities is coupled 21 to 23 «Some of the supply sources, such as the one for logic circuit 13? are essential for the ski eleven enüber _s transmission while others in terms of the transfer are not essential but _s

809 8 35/0 98

only for the operation of the specific point module, device or the like. required are. The failure of one or more of the non-essential voltages is determined by the monitoring device and transmitted to a ■ via a unit 24-A Data frame 11 given in order to inform the control station 7 of the error, as will be explained later in detail is described. The failure of a substantial voltage for loop transmission automatically actuates one Switch device 25 »which switches off the remote station and bridged. As shown schematically, for example the monitoring device 24 is provided with a relay 25 for this Switch connected. The relay has a pair of contacts 25-1 $ which directly connects input 14 to output 15 connect and thus bridge the distant station 8 directly. If there is a corresponding error in the supply voltages eliminated, the seiais 25 automatically switches the remote station 8 back to the transmission loop. A switch 26 in each remote station 8 is for one tone hand operable disconnection of the loop cable 51 from the logic circuit of the station and for reconnecting the loop cable behind the station. So that can A test and maintenance was carried out on the remote station 8 without the normal working method of the the rest of the transmission loop is disturbed.

In addition, each remote station 8 has a generator for the data frame, which is connected to the logic circuit 13 and is responsive to a condition indicative of a loop break on the input side to produce an output signal via the logic circuit to the control station, which is thus informed that the line interruption occurred immediately in front of the respective station 8 is. This loop break detection device is the data frame generator, the a single address for the respective remote station 8

609835/0962.

- ¹⁶ - '2 3 R 5 3 7 ",

holds. The generator 27 is an input timing circuit 28 on, which is connected via the logic circuit 13, to continuously adjust the interval between successive Monitor data frames 11 and 12. If the interval exceeds the maximum permissible interval, the Generator 27 actuated to generate the corresponding data frames containing the address. Within a very short one Zeit thus only generates the remote station 8, which has not received any more data frames due to an interrupted loop, itself such data frames. The control unit can by successively receiving the address of the respective Station identify this station immediately and emit a corresponding output signal. The generator 27 may also have a manually interruptible switch 29 to allow this loop operation with a lower To perform data frame sequence.

In Fig. 3, a new, individual data frame is shown in the form of a module block. The entire frame 11 consists of 36 consecutive bits, which are subdivided into four basic words, each of which has 9 bits on v / e, which are denoted by digits as bits 0 to 8. Each bit position in each word is a digital binary logic signal which is indicated either by a high or a low voltage level according to the usual logic binary signaling and denoted as logic 0 or 1. The logic signals are sent one after the other in the manner described, where the 0 bit of the first word 30, as shown in FIG. 3, is sent by the system, which is immediately followed by bit 1.

The first word 30 gives the frame type and the loop address coding what enables an assignment and availability of the associated frame to the remote stations 8 to 9.

609835/0962

23R5871

If the data frame 11 is assigned to the remote station 8, the logic circuit 13 recognizes the address information and activates the appropriate station to modify the information or data bits. Isn't the lame one for If the corresponding station is addressed, the various j bits received one after the other are only sent to the next Station retransmitted without being modified.

Each of the information frames 11 and 12 can be one of three Types that are available as O-frames, as awarded frames, or are designated as the available frame. The condition of the frame is usually from the first three bits 31 »32,33 of the first word 30 specified. There is an O-frame in all three Bits 31, 32 and 33 of word 30 and over the entire frame a 0 and is usually sent out to prevent an inflow of information from the loop. An awarded Frame has a special address in a plurality of address bits 34- with a special control command. the logic circuit 13 recognizes each address and activates station 8. An awarded frame is therefore a specific one remote station 8 and its point module 16 to 18 and contains a specific operation command for these modules.

Available data frames circulate through the transmission loop and. are a station 8 for remote _v grouting who desires the transmission of information to the central station or at the control point 7 ·. Such available frames may be generally available and selected by a first remote station that is in an on-demand mode. On the other hand, a special or allocated available frame can be generated by the control section 7, which is then restricted to receiving information only from that particular remote station which is addressed in the first word. With that, the

609835/0962.

Control station 7 cause an authorization ranking if it is required. Such a latter data frame naturally becomes information from each point module 16 to 18 within of the remote station 8 that was addressed. A generally available frame has a logical bit 31 1.

Such a frame 11 circulates in the transmission loop between different stations, each bit is analyzed one after the other by the remote station in a hurry and the first remote station to receive a request or an interrupt signal changes the first bit 31 into a logical 0 and also fills the rest of the frame with the desired information. The transformation of the first Bits 31 in a logical 0 removes the generally available Identifier from the frame, making it unavailable to the remaining distant stations.

If an available frame has been switched to a certain remote station is restricted, a logical 0 remains in bit 31, while the second bit 32 remains a logical one wearing. The third through seventh bits 34 of the first word 30 form the address of a particular remote station, if the frame has been awarded to a station.

In the embodiment shown, five bits, namely 3 to 7, are used for addressing the various remote Stations 8 to 9 are provided in both an awarded and ach in an allocated available frame 11, with the data transmission system is designed in such a way that it comprises 31 remote stations 8 and an operating device 9 can.

An allocated available frame can only be used by a

609835/0962

23B5871

signed remote station 8 can be accepted by this inserts an information to be sent to the control point 7 in this. The second bit 33 of the first word 30 is a "general" bit that activates all remote stations 8 at the same time. This is achieved by a logical 0 is provided in the first two digits and a logical 1 in the third or "general bit 33" fourth to eighth bits must be a logical 0 so that the remote station can respond. After all, I know that first word 30 has a final parity bit 35, which indicates the integrity and suitable transmission of the first information word 30 ensures.

The second word 36 of the frame 11 has a pair of acknowledgment bits 37 and 38, which are generated for successive transmission and retransmission immediately following the parity bit 35. The first acknowledgment bit 37 of the second Word 36 is converted to a logical 1 by the remote station 8 changed when the remote station finds its address in bits 34 · and the remote station 8 is ready to answer is.

The second acknowledgment bit 38 is removed from the remote in a logical 1 Stations 8 to 9 changed to a data frame 11 or fill in 12, which circulates as an available frame. The second word 36 then has six consecutive address bits 39 and a final parity bit 40. The bits 39 give ' to and effect the address for any of the point modules 16-18 associated with the remote station 8 thus a coded interlock for activating a certain point module. The next word 41 has a plurality from command bits 4-2 in the beginning part of the word.

609835/0962

236587Ί

Do not recognize the addressed point modules 16 to 18 their address or react accordingly, no acknowledgment signal is generated.

If this is not the case, the command bits 42 of the word 41 are continuously sent out as a logical 0. The control station 7 recognizes upon receipt of such an award Frame that all command bits have a logical 0 as an error of the addressed point module that is on should address the frame 11. The control station 7 can then send back a new data frame with an appropriate command or any output required hand over. In the embodiment shown, the third word 41 has four starting bits 42 for inserting the desired one Command for the specific point module, which thus encode the specific type of operation and function, which is to be carried out by the respective point module.

The logic circuit 13 is four command bits on the Rail 19 to all point modules 16 to 18, but only the activated point module can respond to this coded command and the module switches to the desired operating mode can move »

An instruction parity bit 4J immediately follows bits 42 and must check the data frame in a suitable manner before the command signal is sent to the addressed module.

The third word of the data frame 11 finally has three status bits 44, 45 and 46 and a final parity bit in its sequence 47 on.

The status bits 44 to 46 are activated or filled in by a remote station 8 to the transmission point 7 of to inform the selected operating status of the station. Bit 44 is a detected parity error

609335/0962

2 3 B -S 8 7

assigned to the handling of a data frame. The detection of any of the aforementioned parity errors prevents activation of a point module to perform the commanded mode of operation such as this one command bits 4-2 was specified. In this state, the remote station 8 is in a semi-active state State and it only fills the state bits 4-4-, 4-5 and 4-6 in the data frame and gives the control your st eile 7 their current operating status. -

The second status bit 4-5 is an error in the power supply assigned to the activated remote station 8. As already mentioned in connection with FIG all supply voltages continuously from the monitoring device 24- monitored. Is a supply voltage for the functionality of the remote station on the transmission loop not important, but important for the operation of the point module, bit 4-5 becomes a logical 1 to enable it Information about an error to the control station 7 give. If the supply voltage is important for the operation of the remote station on the transmission loop, then so switches the switch arrangement shown in Fig. 2 off the remote station to a further mode of operation of the transmission loop to enable.

The last status bit 4-6 is from the remote station is used to indicate that a loop break has occurred and that a data frame is required to deliver data the control station 7 to send. This information is used by received the control st eile 7 and accordingly determined that a non-confirmed loop interruption occurred at a remote station that has an available frame or an end acknowledgment frame for clarification the loop interruption is required. In this way

60983570962

can, whenever a remote station 8 either from the Control station 7 or activated by a separate request to send information, the interruption state can only be cleared up by the receipt of a data frame assigned by the control station 7 with a suitable clearing command in the command section 42 Protection against loss of information is important. If an error occurs in the form of a parity error, a bit loss or the like on, the control station 7 recognizes this state and sends a data frame again for subsequent completion off · If, however, a completed, available frame is not received correctly by the control station 7 and the point modules 16 to 18, who had filled out this data frame, were allowed to remove their interruption, is a loss of information possible. The control station 7 therefore controls the deletion or Resetting the interruption and only causing this if a filled in available frame has been received without errors became. If it was not received in this way, the control station 7 simply ignores the incorrectly completed one or the one with errors Affected data frames and the point modules 16 to 18 then receive a further available frame and fill this and continue this until this has been confirmed by an awarded framework.

The eighth or final bit 4-7 of word 4-1 is a parity bit, that ensure the integrity of the information arrangement target.

The final word 4-8 has eight data bits 4-9, from one Final parity bits 50 are followed. The last word will be 4-8 thus also used to send data to the activated point modules 16 to 18 to a specific point or part of the device to select and / or receive from this information according to the commanded state sent to a point module

609835/09 62

16 to 18 was sent out. In this way, an activated point module can have logic circuits that are controlled by the Addressing of the point module are activated and check the operating status in order to only select one of the different Activate points within a unit 21 to 23.

The data frame 11 is in this way bit by bit in the logic circuit 13 processed and, if intended, also from a point module 16 to 18 and the assigned hardware devices 21 to 23 · The bits are then again in modified or non-modified form in a way that allows reliable reading, evaluation and ensure analysis by the control unit 7. The multiple parity check by which a remote station 8 only can be activated ·:., and only its internal units being able to activate i of appropriate parity to perform a commanded operation provides a means of ensuring correct data transmission. The parity checks in connection with positive receipts or confirmations, Checks for supply voltage errors and health checks form a summary through which the Control point 7 i ^ essential immediately from the occurrence of a Problem in the transmission loop of the data transmission system. The fault has only an instantaneous one Character, like a parity error, so can that in the Control station stored program can be set in a simple manner so that incorrect information is rejected and the respective operation is repeated to correct the error to correct. When the repetition of the problem that occurs reaches a noticeable level, the operation becomes the transmission system is worse and this fact is obvious to the operator. The bug doesn't have an instantaneous one Character, is therefore not corrective, but of a more permanent character, such as a component

609835/096 2

or a supply voltage fault, it becomes a positive Generates a signal that indicates the problem to the operator, so that appropriate action can be taken.

In this way, the data transmission system effects complete, asynchronous digital data transmission, which can be expanded or narrowed in order to meet the various application requirements. The separated, having a stored program computer in each control unit is particularly advantageous in that the program can be modified by the internal commands of the stored program _s, and thus a software programming can be adapted easily. In addition, the various remote stations can communicate with the others via the control station 7. For example, the teleprinter 16B can receive and transmit information for the control station. The teletype 16B may therefore contain commands that modify the operation of the control station. The possibility of sending and receiving coded information also allows data to be transmitted between teleprinters 16B or the like at different remote stations 8, as shown in FIG. 1, for example. The various point modules and associated devices can optionally be arranged in the most advantageous structure in each case, the required information being summarized and collected in groups during the operation of the data transmission system. The continuous monitoring of the data transmission and the operational integrity of the data transmission system with built-in devices for diagnosing the circuits and identifying system errors is particularly advantageous if hardware that is present at remote stations is to be controlled in a controlled manner.

In a closed loop communications system, a loop break can occur and it

8098 3 5/0962

■ -25-

is important, the location of this loop break at which determine the error occurs.

In accordance with the exemplary embodiment shown, each remote station 8 is constructed in the same way with a generator 27 for the data frame, with which a sequence of data frames can be generated in a time-delayed sequence.

For example, when operating a system operating in a normal transmission loop, the control station 7 "can generate information bits at a rate of 500,000 per second. The 36-bit data frames 11 and 12 are therefore transmitted in a time sequence at this speed with data-free intervals between successive ones Frames of at least 10 microseconds are generated. However, the minimum overall speed for the generation of data frames will never be less than several thousand data frames per second in a typical application. which does not exceed eg 200 to 500 milliseconds. Each remote station 8 to 9 should therefore receive successive data frames without a delay or interruption exceeding 500 milliseconds. The special data frame generator 27, which contains its own address, monitors con continuous the time delay between successive data frames. If the time interval exceeds a selected level, such as 500 milliseconds, indicating that successive frames of data are not received in the normal minimal manner, the generator 27 begins repeatedly to generate frames bearing its own address. In a practical application, for example, 7 · 7ΟΟ frames per second can be generated.

6Q9835 / 0982

rator continues to generate these frames until an input from its receiver is detected by appropriate logic circuitry. Each of these error indicating frames is sent to all subsequent remote stations. It is assumed that a loop break at point 5I between the first and second receiving station 8. The operating condition at the output or sending end of the control station 7 and the first remote station 8 are normal, so that the control station 7 continues to generate data frames 11 and 12 and the first remote station 8 continues to process these data frames and again * However, there is no data flow over the remaining loop to the control station. Every one selected time interval, such as 200 milliseconds or more, during which the control station 7 does not receive any data frames, the second remote station 8 begins to generate its own data frames 7 receives and reads di ese successive frames at their inputs with the address of this one remote "station * which thus indicates the presence and location of an error condition. The control unit 7 may generate an appropriate information _that} such as generate the location of the fault as well as the nature of the fault on any property with the operator in the message exchange device a teleprinter or the like.

When correcting the cable fault, the second remote station 8 receives the downstream of the message flow Switching point 51 is, one bit above the interrupted one before Cable from the first remote station 8. The first received gene bit terminates the operation of the signal generator 27 and sets the station. 8 so that this again continuously counts the time between successive data signals Supervised. The remote station 8 does not immediately send the

60983 5/0962

• -27-

following bits of the reset frame. However, if a subsequent frame is different from the first, previous remote station is received, "the (reset remote station is back to its normal Receive and transmit operation to "complete the normal operation of the transmission loop again. This The recovery sequence allows the remote station to return to its normal operating state without that this data is interpreted incorrectly or that incorrect data is sent out.

This also ensures that the station 8 is immediately downstream of the loop break point 5Ί from the control station is recognized. So further stations 8 located downstream can have a shorter time interval than others in the Instant of occurrence of a loop break, so that one is immediately next to the loop break station located on the downstream side can generate frames containing its address for include the tax office. However, a very short time after that, the frame generator 27 becomes next to the loop break activated. When the downstream station receives a bit from the upstream station, this will of course end its generation of its own frames and the start of the next following frame wait for the station further upstream. In this way, the timer and reset assemblies automatically ensures that the station 8 immediately downstream of the error that has occurred, the control station 7 with their address applied even if the time interval in a facility located downstream should be shorter than that immediately adjacent to the one that occurred Error neighboring facility.

609 8 35/0 962

This feature of the new data transmission system enables This means that faults can be identified quickly and accurately, without any adjustments or adjustments in the faulty network regarding the position of the device in the transmission loop requires. In this way, every remote station, regardless of its location, addresses in exactly the same way. in order to give a suitable identification to the control center.

In loop control systems, in addition to the control station 7, an operation-supporting device should be provided its 5 which enables input and extraction of information by hand, as well as optional monitoring of the various remote stations. The operating device shown is designed and provided in a special way, to effect these functions and controls. The various elements «, in turn for the actual Function required are readily available and readily understood by one skilled in the art, so that the essential Input and output devices shown only schematically in Fig. 4- and their connections below are described.

4 shows a preferred embodiment of an operating device in which a portable housing 52 is provided for completely enclosing all necessary control devices and is provided with a suitable hinged handle 53 or the like. _{9 is provided to} enable suitable movement and transport of the device to the desired location of the transmission loop. Input-output connections 5 ^ are provided in the housing for connecting the loop cables 10 to the station 9. In addition, the operating device has auxiliary transmission connections 55 for the connection of a special audio cable connected to the various stations 8

609835/0962

on. The transmission system allows acoustic entertainment between the operator at the. Control unit and any one at the distant stations, as well the generation of acoustic alarm signals for detected errors at the remote stations. A headphone jack 56 can be provided and a talk / listen switch 57 switches the circuit to either reception or transmission of acoustic messages. This connection arrangement can also be a horn or other acoustic Alana source, which is not shown here, in order to respond to a detected alarm state in the transmission system. An on-off switch 58 may be provided to selectively to connect the acoustic alarm in the transmission system. The operating device 52 is also with an internal Voltage sources and the like for independent operation provided and has a socket 59 for additional or auxiliary devices for controlling peripheral devices.

In detail, the operating device 52 has internal connection devices for connection with optional modules via socket 59 in accordance with the EIA-Iiom RS232-C. This Herkmal enables a device, like a! Teleprinter 60, a slide projector or the like, the operating device 52 assigned and controlled by the tax office. The teleprinter 60 allows communication with remote stations via the control station and a modified one Operation of the control unit.

The operating device 52 comprises essentially all of the "structural units to »which are also provided for in a conventional remote station, including a logical one Circuit for handling the data frames with an identification circuit for the address of a remote station that has a fixed loop address with a logical 0

609 8 35/0 982

is coded for all bits and on selected dot module addresses responds to distribute the information within the control unit- The in this way from the Control unit 52 formed station 9 is therefore of the usual standardized structure and just as variable as the stations 8, which have special or peculiar input-output devices are adapted to the respective remote stations »

In addition to the usual "processing" circuit, this is Operating device 52 for actions initiating the start of information via the control station 7 in dependence on Changes to the input of any remote station or depending on a particular operator request designed, which is generated on the operating device 52.

In general, the operating device 52 is with a front view - Plate provided with an upper information field 61 and a lower field 62 for input selection signals and displays having"

The upper field 61 has several lamps 63, each of which is appropriately labeled and assigned to a specific remote station 8. If the new data transmission system is to be designed to control 31 remote stations, 31 indicator lamps 6 are provided. Each of the lamps 63 is individually controlled by the data frame 11, which reach the station 9 and thus the operating device 3 ^ via the control station 7 and can be put into any of the three operating positions, such as constantly switched off, constantly switched on or flashing in order to a continuous display of the operation s

35/0962

the monitored remote station. Therefore receives a remote station 8 has an abnormal input signal or has an abnormal operating condition, the assigned one begins To flash lamp 63, with which this operating state and at the same time indicates that the operator this operating condition has not yet been confirmed on the operating device 52 Has. This operating state is activated by the operator on the control unit by actuating a confirmation switch 64 confirmed in the lower field 62. The switch 64 generates an interrupt signal to an acknowledge signal to be sent to the control station 7, which then sends a lamp change signal to the control unit. Upon confirmation, the lamp 63 will be in its continuously lit state State switched. In this way, all of the blinking lamps 63 are turned off upon actuation of the confirmation switch taken into account accordingly by the operator on the control unit, whereby a suitable data frame from the Control point 7 is generated.

The lower. Field 62 v / e is execution switches 64 and 65 as well as a transmission switch 66 on. In this way, the operator at the operating device 52 can initiate the data transmission pick up by actuating one of these three switches, shown as three illuminated pushbutton switches 64-66 are labeled "Send", "Delete" and "Confirm" are. Each of the switches 64 to 66 generates a request or interrupt signal to select one available frame and to insert the address of the control unit in this. This is sent to the control room 7 sent which a subsequent group of awarded frames for the operating device 52 as a result of a stored Program generated.

609835/0962

A group of data switches 67 _s which can be set manually by the operator on the control unit j are also provided for inputting binary-coded information into the data frames 11 or 12. Specifically, the group of switches 67 _{s of} which only a part is shown, address switches 68 for the remote stations, address switches 69 for the point modules and a switch 70 for an internal point for selecting a specific hardware part within the point module on. In addition, with the help of function switches 7 " ¹ of group 67, a command or function code that is to be executed at the respective address is set, which is to be set in a numerical code for a specific operation, the display, control and / or parameter Input functions may include ».

The input of data to a remote station is carried out with the aid of switches 72 for input values which enable the input of up to four decimal digits in a given point.

The actuation of the switch 66 "Send" causes the occupancy of an available frame by the operating device, the insertion of its address and as a result in the control station 7 the generation of a sequence of awarded frames for the operating device to correspond to the group of data switches 67 different input values entered.

The lower display field 62 also includes a numerical display part 73? din den a numerical information in any of several different formats including a floating decimal point or a the field separating marker 7 ^ - · At the left end of the numeric Display part can be a display device 75 for a

609835/0962

Minus signs should be provided for suitable actuation. The numeric display is made using a group actuated by three data frames, which are controlled by the control unit 7 to the control unit 52 with the necessary numerical Information can be given, which can be found in these as a value, decimal, location for the district point and information for the minus is coded

The numeric display 73 is on opposite sides flanked by several indicator lights 76 »77 that indicate the type of numerical information presented. So the lamps 76 on the left side of the numerical display 73 e.g. selected technical units, such as temperature, percent, flow pressures and the like. be assigned to indicate what the numeric display indicates as a function of an analog variable. Will be a If the analog function is not displayed, the lamps 77 give up on the right-hand side the corresponding meaning for the specified numerical information of the non-analog function.

At the bottom of the field a plurality of displays 78, 79 and 80 are provided to provide additional information accordingly the system information present on the numeric display. The three lamps 78 to 80 can indicate a normal or alarm operating condition of the item associated with numeric display 73 while the lamp. 81 can be turned on to show the time of day is shown. An auxiliary indicator lamp can be used for selective Connection can be used when a special function "or an element is connected to the operating device, e.g. a telex or the like.

The actuation of the switch 65 "delete" sends a signal to the control point 7 »by a data frame to the operating

609835/0962

device 52 to send information from display field 73 and the indicator lamps 76, 77 and the indicators 78, 79 and 80 and the time of day together with a corresponding lighting up of the time lamp 81 in the numerical Display 73 to be entered.

Because of their standardized structure and the various facilities with which they connect to the transmission system is connected, the station 9 and in particular the control unit 52 into each of the multiple loop systems 3 to 5 looped in to allow control by an operator on one of the control parts remote body or to support the control center. can.

The new data transmission system thus enables an improved Carry out data transfer and operation of remote operations and collect information Hardware devices that can be functionally combined in groups, such as this for heating, Ventilation and air conditioning systems, as well as other industrial ones Process controls is the case.

A point module 18 at a remote station, the one Two-state control associated with a motor 81a is shown in FIG. 5 with connection with other similar ones or different point modules 16 to 18 via a common input rail 82, which comprises rails I9 and 20, · shown in detail. The point module 18 is connected to the input rail via jointly logically coded lines Addressing the point module 18 and is used for data transmission provided with this with a single binary bit address, which is switched by input 84- for a comparison register 85 is set. A main signal line 86,

609835/0962

with the logic circuit 13 for processing the Data frame is connected, signals a point module that the address is available and actuated with the register output a locking circuit 86a, which feeds a switch-on line 87 and sends the remaining data from the Data frame 11 allows the respective point module. The third word of the data frame is a binary coded command that is sent to the logical command decoder 88 via a Set of latch flip-flops 89 under control the signal line 87 and also a command control line 90 is given, which is acted upon by the logic circuit 13 v / earth. The command signal is decoded by decoder 88 and produces a corresponding single output signal on either a start line 91 or a stop line 92 or a line 93 reading the operating status, which are simultaneously coupled to a plurality of the same selection and driver circuits 94 ·, one of which is im individual is shown. Additional information is now received from the data frame and also sent to the decoder of the selection and driver circuit 94 · given to one of the output lines 96 to activate, wherein the logic circuit 13 generates a signal on the signal line 97, which together with the signal on signal line 87 and the start signal combined on line 98 by a TOTD link will. The selection and driver circuit has a delayed, monostable pulse unit 99, which is connected to a relay 100 is connected to start and stop the motor 81a or another consumer. The pulse circuit 99 is connected to the start-stop lines 91 via NOR elements 101 and 92 through an RS flip-plop latch circuit 102 tied together. The pulse circuit 99 holds the logic circuit in operation for a sufficiently long period of time to allow the switch to be switched to a locked operating state to enable. The relay circuit is used with separate supply sources 103 and 104- to lo-

60983 5/0962

isolate and protect electrical circuits from the circuits operating the motor. A start relay 105 and a stop relay 106 are alternately from the output signals of the
Elements 101 are set in order to selectively start and stop the motor 180a, in that a feed line with a start connector 107 and a stop connector 108 is established.

A common reset busbar 109 is provided for resetting registers 86a and 89 and for resetting the logic circuits. A positive acknowledgment signal must be sent to the point module 18 in order to delete or switch off the point module. The operating condition of the engine is continuous by detecting the contact condition
monitored by a relay 110 that detects this state, the contacts of which are connected to a signal line 111, to transmit a signal to a register 112 and a comparison circuit 113, such as an EXCLUSIVE-OR gate and to a
To give rail line 114- to send the detected operating status to an information system. The output signal of the register 112 is compared with the contact to stand by the comparison switch 113 and given to actuate an interrupt lock 115. Are both
not in the same operating state, an interrupt signal is generated which indicates that an available frame is available for the
Sending out information is needed. The control room
then gives the command to the remote station, the state
to read out and the status condition to the control units
to send. At this point, a command signal activates a read line 93 in place of the start or stop lines and causes the transmission of status information which an address setting and interlocking system can use to receive the signal to start and stop the motor.

60983 5/0982

The bit signals can be generated and sent as shown in Fig. 6, where a pair of switches 115 alternate a pair of capacitors 116 into one Transformer 117 discharges to produce a bipolar bit signal, the bit signals being separated from each other by zeros are separated to define a logical information bit 117.

Each bit signal 117 can have a total length of 2 microseconds where the pulse with the initial polarity is generated at 5/10 microseconds, followed by a same pulse of opposite polarity, followed finally by a zero signal of about 1/2 bit period length The information is transmitted via the transmission lines 10. The first polarity pulse of the bit signal 117 is sensed by a receiver which is a coupling transformer 118 and polarity sensitive members 119 to generate a square wave signal. The leading flank of the first polarity pulse is used to set a flip-flop data register 120 and turn it on a monostable, reversible circuit 121 is used, to generate a timer pulse, which is a pre-clock pulse of about half the period length of the first polarity interval is defined. The trailing edge of the pre-clock pulse controls, for its part, a back-steerable after a long time, monostable circuit 122, which has a time interval equal to approximately half the total time of the bit period Has. The output signal of the second timing circuit 122 generates the clock signal for the data transmission in the register stored data. The output of the station can therefore be a transmitter similar to the components 115 to 117 »a parity checking device and other logical means for handling the data frames and processing each data frame in the form of a bit flow through it

6098 35/0962

point. The output of the clock circuit 122 is also with the circuit 121 for the gate clock pulses and the receivers 118 to 119 connected to actually a further signal formation by these latter two circuits and the Prevent reception of the impulse of the second polarity of the bipolar signal by preventing it from being sent out Impulse does not need to be waited - it also prevents the detection of signals on the receive lines while the duration of which erroneous noise or other erroneous information appear on the line and an erroneous one Work can cause.

Me clock pulses derived from the polarity pulses set the operation of the transmission system for continuous data transmission of successive bits of Data frame as long as at least one pulse per period is generated.

If the second polarity pulse of the bipolar signal is lost for any reason, e.g. due to noise, then the data transmission system is not affected, as this pulse occurs during normal data transmission on the first impulse is not used. If, on the other hand, the first pulse of the bipolar signal is lost, the received data will be incorrect. However, the parity check of the received data indicates such an error.

A cancel signal is provided by a monostable circuit 123 generated, which is set during the period of the pre-clock pulse and has a relatively long switching period, so that they are not during the duration of the 0-signal portion of the Bit signal 117 switches. However, there is a relatively long signalless period between the data frame 11, whereby the switching time of the circuit 123 is ended and the processing prevents facilities for the data frames from to respond to the next new data frame.

609835/0962

Claims (2)

PATENTANW ^; U. f E H. KiNKELDEY DfWNCi 23658 71 W * STOCKMAI R DP.-IKG. · Ar.P! CAIlECH) . , K. SCHUMANN '■ " DR FERfIiAT-C-Pl -PHYS P. H. JAKOB DIPL-ING G. BE-IZOLD Because PEUNAT-- DS ³ L-CHLJA Ö MUNICH 22 MAXIMILIANSTRASSE 43 P? 549 TI- · 52 / April 1, 1-976 Patent claims MJ data transmission system with a control unit with several remote stations can transmit data frames connected transmission loop, the multiple supply voltage sources for the delivery of several operating voltages, these voltages in the first, important for the operation of the remote station, and in the second, for the loop transmission important voltages are divided, indicating that the remote stations (8, 9) have a voltage monitoring device (24-) with which at Occurrence of a voltage failure at a second voltage the remote station can be bridged and if one occurs Voltage error with a first voltage an error message containing data frame can be sent to the control point (7). ·! 2. Data transmission system according to claim 1, characterized . characterized that an input (14) and a Output (15) for the cable (51) forming the transmission loop - for receiving and sending digital information 60983570962 TELETOM (Ο1.5) 2226G2 TELEX O;, - Ct530O TCLEdRAMMf MONA "/ T are provided in serial form, and that the monitoring device (24-) has a switch (25) connecting the input directly to the output, which switches to an error in a second voltage responds to establish this connection. 809835/0962 Le first