DE102004058940B4 - Detector unit and method for data transmission - Google Patents

Abstract

Detector unit (11) for a detector system with a plurality of detector units,
wherein the detector unit has a sensor section (23), the detector unit further having at least one serial data input (RxD) and one serial data output (TxD) on a first coupling side (13) and a second coupling side (15) in such a way that the detector unit can be coupled on its first coupling side to the second coupling side of a similar detector unit and on its second coupling side to the first coupling side of a similar detector unit, thereby enabling bidirectional communication between a plurality of detector units in a series coupling,
wherein the detector unit further comprises a control circuit (17), which is designed for sending data packets (41) to coupled detector units and for receiving data packets (41) from coupled detector units, wherein the data packets at least one receiver address (42), a sender address (43) and a command identifier (45) and wherein the control circuit (17) for sending data packets (41) independently of a clock signal of a higher-level master unit and to the ...

Description

The The invention relates to a detector unit for a detector system with several Detector units. The invention further relates to a method for transmission data between multiple detector units of such a detector system.

A Such detector unit has a sensor section in which For example, it is a complete sensor, part of a Sensors (eg transmitter or receiver) or an optical, electronic or electrical interface can act as a sensor. For example, as a sensor Photocell, a reflection light sensor, an inductive proximity sensor, a capacitive proximity sensor or an ultrasonic sensor may be provided. The detector unit contains Furthermore an evaluation, control and communication electronics. Within a detector system is a coupling in close spatial arrangement provided by several such detector units with each other, for example, the exchange of read data or control data enable. For this purpose, a series coupling of the detector units has proven, wherein the detector units on a first coupling side and on a second coupling side in each case a serial data input and have a serial data output. The detector units become coupled together in series such that the detector units at their respective first and second coupling side with the respective one second or first coupling side of the adjacent detector units are connected. about the respective data input and data output on each coupling side can the detector units thus communicate bidirectionally with each other.

at the known detector units sometimes cause compatibility problems when multiple detector or other units are coupled together be in terms of their communication structures and protocols not completely identical are.

A detector unit according to the preamble of claim 1 is in the EP 1 223 710 A2 disclosed. From the DE 199 06 867 C1 a method according to the preamble of claim 23 is known.

It It is an object of the invention to communicate between several detector units coupled together in series faster and faster more robust.

These The object is achieved by a detector unit having the features of the claim 1 solved.

The The object of the invention is also achieved by a method having the features of claim 23 solved.

It Thus, it is provided that the communication between a detector unit and a coupled similar detector unit in the form of Data packets, these data packets being independent of a possible clock signal of a higher-level master unit can be sent and received. The data packets contain a recipient address for identifying the detector unit within a detector system, which should receive the relevant data packet. It has to be Naturally not necessarily be a detector unit that sent to the sending Detector unit is coupled directly adjacent, but It can also be provided that the data packet of several in Row of coupled detector or other units up to the final receiver is forwarded. The data packets also contain at least a sender address for identifying the sending detector unit and a command identifier, in which, for example, a data request or a control command is encrypted is. Through the use of data packets with recipient address, sender address and Command ID is a remote point-to-point communication possible between different units. Under a data package is in this context a closed record according to a to understand predetermined data structure.

By doing each detector unit independent send data packets from a global synchronization signal or can receive the detector units should only be designed so that the respective Control circuit or an interface driver contained therein at the serial data inputs and data outputs the detector unit with data outputs or inputs of a similar unit is able to communicate, so that between the respective detector unit and a directly coupled Unit a data packet can be exchanged. To a system of To expand several detector units, so it is only necessary to couple such similar detector units together. On the other hand, it is not necessary to have a "master / slave" hierarchy to realize. compatibility issues are thereby avoided, and also the connection of other units to the detector system, such as from external control units or bus adapter units, is facilitated.

The ability to exchange data packets independently of the control of the actual sensor of the respective detector unit, while the response time of the relevant sensor he heights. However, it has been found that acceptable limits can be defined. In contrast, there is the advantage that the data packets can be exchanged particularly quickly and flexibly between different detector units, since the communication takes place independently of the synchronization of the respective sensor sections of the detector units. It is thus only necessary that the respective detector units have the same interfaces.

One further advantage of the explained Exchange of data packets is that both a local Operation of the detector units is possible as well as external Commands supplied and taken into account can be for this both cases the same logical interface is provided. By using Each message identifier may have different data packets be differentiated from each other.

Around the communication of a detector unit with a coupled similar detector unit without additional clock line to allow each detector unit comprises an internal clock having a Generated read / write clock, wherein the sending and receiving of Data packets or parts thereof according to this read / write clock is controlled. Of course should all Detector units of a system with the same read / write clock work, whereby unavoidable slight deviations by a Self-adjustment due to the actually received bit rate can be compensated. The control circuit or an interface driver contained therein transmits or read a data packet at the data output or input, for example bytewise according to the internal Read / write, with a pause between two consecutive Data packets through a signal gap For example, is characterized by at least one byte or based such a signal gap is recognized.

According to the invention for the sent or received data packets provided a constant length. This can namely a dynamic memory management are realized in the for the Save and process the data packets only pointers are changed have to, the position of the relevant data packet within one Show memory. The copying of complete data packets into different ones Areas of the memory is eliminated. Thus, ultimately, there is a smaller amount of physical space required.

The Detector unit has a data packet memory in which the received or data packets to be sent. There are two Transmit queue memory provided, the first coupling side the detector unit and the second coupling side are assigned. These send queue stores are in several queue sections divided, in each of which a memory address pointer is stored that points to such a data packet in the data packet memory, the above the data output of the relevant coupling page are sent should. Thus, you can the received and to be sent data packets in unmodified Position remain stored within the data packet memory, while the management of data packets - for example by means of a message broker or an interface driver the control circuit - over the Memory address pointers are stored in the send queues to get managed. Copying the entire data packet within the data packet store is not required for this.

Farther It is preferred if the data packets - as already mentioned - additionally a Message identifier included by the control circuit of those Detector unit is generated in which the data packet generated or from which the data packet is sent. This allows a data packet, the sent from a detector unit to a coupled detector unit is to be distinguished from such a data packet, which is from the relevant detector unit to the same coupled detector unit is sent. This avoids ambiguity.

According to one another preferred embodiment sends the control circuit to a detector unit - after at this detector unit a data packet has been received, the according to the recipient's address for this Detector unit was determined - a corresponding acknowledgment data packet the sender of the received data packet. This is for the sender a data packet control possible whether the intended recipient the Data packet actually has received. For example, it is possible to check in the sending detector unit, whether within a predetermined time interval after sending a Data packets received an associated acknowledgment data packet and in the case of a negative result of this review, the previously sent data packet is sent again. This new one Submitting the data packet is at least for a predetermined number repeated attempts; thereafter the connection between the sending Detector unit and the intended recipient, for example, as interrupted considered.

Such a receipt acknowledgment is particularly simple if the request identifier of the acknowledgment data packet corresponds to the request identifier of the originally transmitted data packet, wherein only a part - for example, a bit - the request identifier is modified to identify the relevant data packet as an acknowledgment data packet. As a result, the sender of the acknowledged data packet can also assign the acknowledgment data packet particularly easily to the acknowledged data packet.

If in the command identifier of the data packet to be acknowledged a request or a data request is included, the associated one contains Acknowledgment data packet preferably has a corresponding response value. In other words, the acknowledgment data packet also serves as Response to the request or request in question, so not sent two separate data packets to the sender of the request Need to become.

It has already been explained that the sending of data packets regardless of a clock signal of a parent Master unit is done. Nevertheless, the detector unit can be used in addition to the mentioned data inputs and data outputs the first and second coupling side a respective synchronization port for receiving and outputting a detector synchronization signal for the Have sensor section of the detector unit, said synchronization ports directly or indirectly via the control circuit are connected to the detector unit. One Such a detector synchronization signal is used for mutual synchronization the sensor sections of the various detector units. This can For example, in connection with optoelectronic sensors helpful be to cause a mutual visual interference or disturbance avoid. The transfer However, the Detektorsynchroni sationssignals is independent of the (asynchronous) transmission the data packets, and vice versa, the sending of the data packets - as already done explained - regardless of such a detector synchronization signal. This ensures that that the data packets without consideration sent to the detector synchronization signal temporally flexible and can be received. Furthermore can for the data communication between the detector units a comparatively simple protocol that is not used to the vote instructed with a detector synchronization signal.

The The invention finally relates also to a detector system with a plurality of detector units of the explained Kind, whereby this system additionally also other units, such as external control units, Bus connection units or other communication or adapter units included can.

Further embodiments are in the subclaims called.

The The invention will now be described by way of example only explained on the drawings.

1 shows the construction of a detector unit.

2 shows a detector system with a plurality of detector units according to 1 ,

3 shows a data packet.

4 shows a memory with a data packet memory and a plurality of queue memories.

In the 1 shown detector unit 11 has a first coupling side 13 and a second coupling side opposite thereto 15 , The two coupling sides 13 . 15 are also called "east" side and "west" side of the detector unit 11 designated.

The detector unit 11 has on both coupling sides 13 . 15 an optional power supply terminal Vcc, a ground terminal GND, a serial data input RxD, a serial data output TxD and an optional synchronization terminal INT. The power supply terminals Vcc of the two coupling sides 13 . 15 are directly connected to each other and become inside the detector unit 11 just tapped. The same applies to the two ground connections GND. All of these connections are with a control circuit 17 connected. The connections of the first coupling side 13 and the terminals of the second coupling side 15 are symmetrically arranged except for the data inputs RxD and the data outputs TxD. The latter are mutually interchanged. This means that the detector unit 11 for example, on its first coupling side 13 can be coupled to the second coupling side of a similar detector unit such that the data input RxD of a detector unit 11 with a data output of the other detector unit and a data output TxD of the one detector unit 11 is connected to a data input of the other detector unit. In a corresponding manner, the detector unit shown 11 be coupled at its second coupling side with a first coupling side of a similar detector unit. The detector unit 11 is thus complementary with respect to the "east" direction and the "west" direction, so that a plurality of detector units of the type shown can be coupled together in series.

The control circuit 17 is also with a clock 19 and a memory 21 connected. In addition, the control circuit 17 with an opto electronic sensor 23 connected, for example, has an optical transmitter, an optical receiver, an associated amplifier circuit and an evaluation circuit. Said transmitter and said receiver do not necessarily have to be in the housing of the detector unit 11 can be included, but can with the detector unit 11 also be electrically connected via optical fibers or via line. The optoelectronic sensor 23 For example, it can serve as a light barrier or as a reflection light scanner.

The detector unit shown on the one hand fulfills the function of the optoelectronic sensor contained therein 23 to supply with energy and with the necessary control commands; on the other hand, signals of the optoelectronic sensor 23 - optionally after further processing such as a threshold comparison - are output via the data outputs TxD. A particular advantage of the shown construction of the detector unit 11 is that the detector unit 11 can be coupled in series with similar detector units or other units to a detector system, and that between the thus coupled units a particularly simple and stable communication is possible. For this purpose, the data exchange takes place in the form of data packets, wherein the transmission of a data packet from the detector unit 11 to a coupled similar unit without taking into account a clock signal of a possible higher-level master unit, ie, such a master unit is not required to allow communication between the units. This will be explained in more detail below.

In the context of the invention, a "similar" unit is to be understood as meaning a unit which, with regard to the communication structure, is identical in construction or at least similar to the detector unit 11 according to 1 is.

2 shows a detector system with multiple detector units 11 according to 1 as well as with an optional bus connection unit 31 , The detector units 11 are coupled in series and connected together in a space-saving manner. The data input and the data output of the one detector unit 11 are connected to the data output or the data input of the respectively adjacent detector unit 11 coupled, as already explained. At the respective first coupling side 13 and second coupling side 15 can a connecting portion - in particular a connector portion - for the direct coupling of the detector units 11 be provided.

At the according to 2 The extreme right end of the series arrangement is exemplified by the bus terminal unit 31 coupled. This optionally has a power supply module 33 , for the power supply terminals Vcc and the ground terminals GND of the detector units 11 provides the required electrical voltage. Furthermore, the bus connection unit has 31 an adapter module 35 , which forms an interface for the below-described data communication between the detector units 11 on the one hand and externally to be connected control or evaluation devices on the other hand, where necessary, an adjustment of the electrical signal level and an adaptation to different bus protocols. In addition, a mechanical adaptation to a conventional connector, for. B. the done an RS232 interface.

Deviating from 2 can be a set of coupled detector units 11 also autonomous - ie without additional coupled bus - are operated, the detector units 11 can communicate with each other. However, it is always necessary to supply an electrical voltage at at least one end of the series arrangement via the voltage supply and ground connections Vcc or GND located there. An advantage of in 2 shown series coupling is that for all detector units 11 only in a single place the power supply must be connected.

To the detector unit 11 according to 1 and the detector system according to 2 It should also be noted that the data inputs RxD and data outputs TxD can be designed as optical interfaces or as electrical connections.

3 shows a possible format of the data packet 41 as it is between the detector units 11 is exchanged. Preferably is for different data packets 41 always the same length provided, for example, nine bytes. In the data package 41 according to 3 are a recipient address 42 (one byte), a sender address 43 (one byte), a message identifier 44 (one byte), a command identifier 45 (one byte), parameter values 46 (four bytes) and a check digit value 47 (one byte). The recipient address 42 and the sender address 43 denote the desired recipient or the sender of the data packet 41 , The message identifier 44 serves to uniquely identify the data packet 41 For example, in the case that a detector unit 11 several data packets with the same command identifier 45 sent to the same recipient. The command identifier 45 indicates after a predetermined key a control command or a request or a data request. The parameter values 46 For example, according to the error code in the Be 45 encrypted control command or with the requested data. The check digit value 47 serves to Check if the data packet 41 correctly and completely received.

4 shows the structure of parts of the memory 21 according to 1 , The memory 21 has one as a data packet memory 51 provided section. This in turn is in several data packet storage sections 53 whose size is the length of the data packets 41 according to 3 corresponds to (nine bytes).

Furthermore, the memory has 21 a send queue memory 55 for the first coupling page 13 the relevant detector unit 11 , a send queue memory 57 for the second coupling side 15 , a send request queue memory 59 , an acknowledgment queue memory 61 , a receive queue memory 63 for the first coupling page 13 and a receive queue memory 65 for the second coupling side 15 , Each of the queuing memories mentioned 55 . 57 . 59 . 61 . 63 . 65 is in several queue sections 67 divided. In at least some of the queue sections 67 Memory address pointers stored on a data packet storage section are stored 53 of the data packet store 51 or a data packet stored therein 41 show how in 4 is illustrated by arrows and as will be explained below.

The following is the operation of the detector unit 11 according to 1 and the detector system according to 2 explained.

Sending and receiving a data packet 41 is done according to a read / write clock of the clock 19 the relevant detector unit 11 : In case of sending a data packet 41 causes the control circuit 17 or an interface driver included therein, that with each read / write clock is a part of the data packet 41 , for example one byte at a time, is output serially at a data output TxD. Receiving a data packet 41 happens in a corresponding manner, ie with each read / write clock of the clock 19 reads the control circuit 17 or an interface driver contained therein, a part of the incoming data packet 41 at the relevant data input RxD serially and sets the received data to the complete data packet 41 together. Between two data packets to be sent one after the other 41 are for a predetermined minimum number of read / write clocks of the clock 19 no data is output to the relevant data output TxD, so that the control circuit 17 the coupled receiving detector unit 11 can detect the end of a data transmission or the beginning of a new data transmission.

The read / write clock is for all detector units 11 a system uniformly set, so that an additional clock line between two coupled detector units 11 is not required. In particular, the sending and receiving of data packets takes place 41 also independent of a clock or synchronization signal of a higher-level master unit; such is not required.

Sending and receiving data packets 41 is also independent of signals that are transmitted via the synchronization ports INT. About the synchronization terminals INT detector synchronization signals are transmitted, which are used to coordinate the optoelectronic sensors 23 the different detector units 11 a detector system serve to avoid mutual optical interference by emitted light signals. The communication of the detector units 11 about the data packets 41 is independent of this.

The communication between the detector units 11 is thus very flexible in terms of time, allowing a fast and trouble-free data exchange between the detector units 11 is possible.

The control circuit 17 Each has an interface driver for the serial data input RxD and for the serial data output TxD of each link side 13 . 15 and a news broker who receives the data packets to be received and posted 41 and managed their forwarding. If the already mentioned evaluation circuit of the optoelectronic sensor 23 not already in the control circuit 17 integrated, the control circuit can 17 Furthermore, an interface driver for the optoelectronic sensor 23 have. The control circuit 17 or a part thereof is in particular also for the local parameterization of the relevant detector unit 11 responsible.

The data packets 41 have - as already mentioned - a constant length. This makes it possible for the data packets received or to be sent 41 within the data packet store 51 always in the data packet storage sections 53 are stored, which also have a constant length. To manage the data packets 41 for example, if a data packet 41 it is not necessary to send the data packets 41 inside the store 21 Instead, it is sufficient to modify memory address pointers corresponding to the data packet concerned 41 in the data packet memory 51 show and those in the queue stores 55 . 57 . 59 . 61 . 63 . 65 are stored.

Sending a data packet 41 is in the control circuit 17 for example, handled as follows:
Trigger for sending a data packet 41 is either a corresponding requirement of the optoelectronic sensor 23 (for example, to forward a receive signal), receiving a data packet 41 from a coupled detector unit 11 , wherein this received data packet 41 must be forwarded or acknowledged, or a control command entered by a user.

If due to the request by the optoelectronic sensor 23 a data packet to be sent 41 is recreated, the data in question becomes a free data packet storage section 53 written. Here, a memory address pointer in the send request queue memory shows 59 to the relevant data packet storage section 53 , Once the data packet 41 completed, the control circuit ensures 17 or the message broker that the memory address pointer, which is still on the data packet 41 or the relevant (unchanged) data packet storage section 53 indicates from the send request queue memory 59 either in the send queue memory 55 or the send queue memory 57 is moved. The selection of the memory 55 or the memory 57 takes place depending on the recipient address 42 of the data packet 41 , that is, depending on whether the data packet 41 at the first coupling side 13 or on the second coupling side 15 the detector unit 11 must be spent to reach the intended recipient.

The order of the queue sections 67 within the two send queue memories 55 . 57 serves as a respective priority identifier, ie to determine the order in which the relevant data packets are to be output by the respective interface driver. In the process, those data packets are received 41 the highest priority identifier, not at the instigation of the optoelectronic sensor 23 but at one of the data inputs RxD of the detector unit 11 have been received and according to the respective recipient address 42 only to another detector unit 11 to be forwarded (so-called routing). For all other data packets 41 becomes the send queue memory concerned 55 . 57 in turn padded.

Each queue section 67 the send queue memory 55 . 57 can also be a status identifier to identify the current send status of the relevant data packet 41 be assigned. In this way, the message broker can be shown, for example, whether a queue section 67 it is just empty whether the data packet in question is ready to be sent or whether the relevant data packet 41 is being sent.

So after the optoelectronic sensor 23 a data packet 41 has been sent, causes the control circuit 17 or the message broker, that the allocated memory address pointer from the respective send queue memory 55 . 57 in the acknowledgment queue memory 61 is moved, with the relevant data packet 41 still in the same data packet storage section 53 of the data packet store 51 remains stored. In the acknowledgment queue memory 61 Memory address pointers stored on such data packets are stored 41 show that have already been sent and are still awaiting acknowledgment by the recipient. For those in the acknowledgment queue memory 61 marked data packets 41 checks the control circuit 17 whether within a predetermined time interval after sending the data packet 41 an associated acknowledgment data packet is received. If this is not the case, the relevant data packet 41 sent again.

If sending a data packet 41 not from the optoelectronic sensor 23 but by the prior receipt of this data packet 41 is triggered and the data packet 41 only to be forwarded (routing), so is a memory address pointer to this data packet 41 in the data packet memory 51 shows in that send queue memory 55 or 57 filed, which corresponds to the correct transmission direction. The message broker selects the highest priority identifier for this data packet 41 , so that the forwarding to the receiver takes place as promptly as possible. Moving the memory address pointer into the acknowledgment queue memory 61 does not take place in this case, ie it is not checked whether a corresponding acknowledgment data packet is received.

In both cases - that is, regardless of whether the sending of a data packet 41 through the optoelectronic sensor 23 or by previously receiving this data packet 41 is triggered at a data input RxD - provides the control circuit 17 or the message broker that the data packet 41 according to the recipient address contained therein 42 only sent in one direction, ie only on one coupling side 13 or 15 is issued. This ensures that the by the series-coupled detector units 11 formed bus not unnecessary with data packets 41 is charged.

Receiving a data packet 41 to egg Data input RxD of a detector unit 11 is handled as follows, for example:
The data packet received via the relevant data input RxD and the associated interface driver 41 gets into the data packet store 51 written, and in the relevant coupling page 13 or 15 associated receive queue memory 63 or 65 a memory address pointer is set which is applied to the data packet storage section 53 shows in which the received data packet 41 is stored. Also the queue sections 67 the receive queue memory 63 . 65 may include a status identifier that identifies the current receiving status of the message broker's packet in question (for example, receive, receive complete).

After the data packet 41 has been completely received, the control circuit checks 17 first, based on a predetermined calculation scheme, whether the received data packet 41 a correct check digit value 47 contains and thus has been received correctly and completely. In case of a negative result of this review will be the data package 41 discarded, ie the relevant memory address pointer is deleted and the data packet 41 will not be forwarded or processed, nor will there be a "negative" acknowledgment data packet to the sender of the incompletely received data packet 41 sent.

In the case of a positive result of checking the check digit value 47 is first based on the recipient address 42 after that distinguished whether the data packet 41 only to be forwarded (routing) or for the own detector unit 11 is provided. In the former case, the data packet becomes 41 immediately forwarded with the highest priority identifier, as already explained.

If, however, the data packet 41 for your own detector unit 11 is determined, it is done according to the command identifier 45 of the data packet 41 a further processing of the data packet 41 wherein, for example, a corresponding control command to the optoelectronic sensor 23 is issued. If it is according to the command identifier 45 is a data request, the requested data becomes parameter values 46 in the data package 41 written or overwritten. If it is clear from the command identifier that the received data packet is 41 is an acknowledgment data packet, then the corresponding, previously sent data packet 41 in the data packet store 51 and the associated memory address pointer is retrieved from the acknowledgment queue memory 61 deleted.

Finally, the received data packet 41 - if it is not already an acknowledgment data packet - sent as an acknowledgment data packet back to the sender. For this, the recipient address 42 and the sender address 43 reversed. The message identifier 44 remains unchanged to allow the original sender to identify the acknowledgment data packet. Within the command identifier 45 For example, a single bit, for example, the least significant or most significant bit, is changed to the data packet 41 as an acknowledgment data packet to identify. In addition, the check digit value 47 recalculated and overwritten accordingly. The acknowledgment data packet is now sent to the sender of the original data packet 41 sent. For this purpose, the corresponding memory address pointer, depending on the required transmission direction in the transmit queue memory 55 or 57 postponed. The acknowledgment data packet can now be output by means of the relevant interface memory.

Along their arrangement direction, the detector units coupled to a detector system have 11 according to 2 ascending or descending addresses. This allows a detector unit 11 in connection with a recipient address 42 or a sender address 43 a data packet 41 recognize if a data packet to be sent 41 at the first coupling side 13 or on the second coupling side 15 is to spend. In order to obtain a corresponding address assignment, the control circuit 17 each detector unit 11 or any other coupled entity 31 for performing the following address allocation operation:
First, after turning on the respective detector unit 11 checked, whether at a predetermined coupling side 13 or 15 another unit 11 . 31 is coupled. This test can be checked, for example, based on a predetermined "ping" signal. In case of a negative result, the control circuit 17 the own detector unit 11 a predetermined address to (eg, 0000), and it gives on the other coupling side 15 respectively. 13 a corresponding address signal. In the case of a positive result of the illustrated test, the control circuit receives 17 at the predetermined coupling side 13 or 15 said address signal and has its own detector unit 11 a (ascending or descending) adjacent address to. At the other side of the coupling 15 respectively. 13 In turn, a corresponding address signal is output. By each detector unit 11 according to this scheme, starting from that detector unit 11 located on said predetermined coupling side 13 or 15 has no coupled neighbor, in turn Assign ascending or descending addresses.

The immediate neighbors of a detector unit 11 however, they can always be addressed directly, regardless of their address along the array. For this purpose, two special neighbor addresses are additionally defined, which are always the respective neighbors on the first coupling side 13 and the respective neighbor on the second coupling side 15 mark. For this purpose, the smallest and the largest address in the address space used are preferably provided, for example the addresses 0000 and 0xFF with an address space of 0000 to 0xFF. These special addresses are also preferably used for the explained "ping" signal.

11

detector unit

13

first coupling side

15

second coupling side

17

control circuit

19

clock

21

Storage

23

optoelectronic sensor

31

Bus interface unit

33

Power supply module

35

adapter module

41

data packet

42

recipient address

43

return address

44

message identifier

45

command identifier

46

parameter values

47

Prüfzifferwert

51

Data packet memory

53

Packet memory section

55

Transmit queue memory for the first coupling page

57

Transmit queue memory for the second coupling side

59

Send request queue memory

61

Receipt confirmation queue memory

63

Receive queue memory for the first coupling side

65

Receive queue memory for the second coupling side

67

queue section

Vcc

Power supply terminal

GND

ground connection

RxD

data input

TxD

data output

INT

synchronization connection

Claims (28)

Detector unit ( 11 ) for a detector system with a plurality of detector units, wherein the detector unit has a sensor section ( 23 ), wherein the detector unit further comprises on a first coupling side ( 13 ) and on a second coupling side ( 15 ) each having at least one serial data input (RxD) and a serial data output (TxD) in such a way that the detector unit can be coupled on its first coupling side to the second coupling side of a similar detector unit and on its second coupling side to the first coupling side of a similar detector unit to thereby enable bi-directional communication between a plurality of detector units in a series coupling, the detector unit further comprising a control circuit ( 17 ) used for sending data packets ( 41 ) to coupled detector units and for receiving data packets ( 41 ) is formed by coupled detector units, wherein the data packets at least one receiver address ( 42 ), a sender address ( 43 ) and a command identifier ( 45 ) and wherein the control circuit ( 17 ) for sending data packets ( 41 ) independent of a clock signal of a higher-level master unit and for outputting a data packet ( 41 ) according to the recipient address contained therein ( 42 ) only on one coupling side ( 13 or 15 ), characterized in that the control circuit ( 17 ) for receiving and sending data packets ( 41 ) of constant length, that the control circuit ( 17 ) with a data packet memory ( 51 ) in the received or to be sent data packets ( 41 ) are stored, that the control circuit at least with one of the first coupling side ( 13 ) associated transmit queue memory ( 55 ) and one of the second coupling side ( 15 ) associated transmit queue memory ( 57 ) connected to queue sections ( 67 ), wherein in each queue section a memory address pointer can be stored which can be stored on such a data packet ( 41 ) in the data packet memory which, via the data output (TxD) of the relevant coupling side ( 13 . 15 ) and that everyone in the send queue stores ( 55 . 57 stored memory address pointer is assigned a priority identifier, which determines the order in which the memory address pointer associated data packet ( 41 ), whereby those data packets ( 41 ) receive the highest priority identifier which is present at one of the data inputs (RxD) of the detector unit ( 11 ) and according to the recipient address contained in the data packet ( 42 ) to another unit ( 11 ) should be forwarded. Detector unit according to claim 1, characterized ge indicates that the detector unit ( 11 ) an internal clock ( 19 ) for generating a read / write clock, wherein by means of the STEU ( 17 ) the sending and receiving of data packets ( 41 ) or parts thereof on the basis of the read / write clock is controllable. Detector unit according to claim 2, characterized in that the control circuit ( 17 ) is designed in such a way that between two data packets to be sent one after the other ( 41 ) no data are sent for a predetermined minimum number of read / write clocks. Detector unit according to one of the preceding claims, characterized in that the control circuit ( 17 ) is designed in such a way that the control circuit alone due to appropriate request of the sensor section ( 23 ), due to the receipt of a data packet ( 41 ) or due to a user-initiated control command starts processing and / or sending a data packet. Detector unit according to one of the preceding claims, characterized in that each queue section ( 67 ) a status identifier for identifying the transmission status of the relevant data packet ( 41 ) assigned. Detector unit according to one of the preceding claims, characterized in that the control circuit ( 17 ) with a send request queue memory ( 59 ) in which memory address pointers can be stored which are stored on such data packets ( 41 ) in the data packet memory ( 51 ) currently being used for submission to an attached unit ( 11 ) to get prepared. Detector unit according to one of the preceding claims, characterized in that the control circuit ( 17 ) with an acknowledgment queue memory ( 61 ) in which memory address pointers can be stored which are stored on such data packets ( 41 ) in the data packet memory ( 51 ), which have already been sent but for which no acknowledgment data packet has yet been received. Detector unit according to one of the preceding claims, characterized in that the control circuit ( 17 ) with one of the first coupling side ( 13 ) receive queue memory ( 63 ) and one of the second coupling side ( 15 ) receive queue memory ( 65 ) in which memory address pointers can be stored which are stored on those data packets ( 41 ) in the data packet memory ( 51 ), which have been received via the data input (RxD) of the relevant coupling side and have not yet been further processed by the control circuit. Detector unit according to one of the preceding claims, characterized in that the data packets ( 41 ) additionally a message identifier ( 44 ), by which a data packet which is sent by the detector unit to a coupled detector unit, is distinguishable from a further data packet, which is sent from the detector unit to the same coupled detector unit. Detector unit according to one of the preceding claims, characterized in that the data packets ( 41 ) additionally at least one parameter value ( 46 ) contain. Detector unit according to one of the preceding claims, characterized in that after receipt of a data packet ( 41 ), according to the recipient address ( 42 ) for the own detector unit ( 11 ) was determined by means of the control circuit ( 17 ) an associated acknowledgment data packet can be sent to the sender of the received data packet. Detector unit according to claim 11, characterized in that by means of the control circuit ( 17 ) a part of the command identifier ( 45 ) of the data packet ( 41 ) is modifiable to identify the dispatched data packet as an acknowledgment data packet. Detector unit according to one of claims 11 or 12, characterized in that in the case that in the received data packet ( 41 ) a request was included, the acknowledgment data packet already contains a response value. Detector unit according to one of the preceding claims, characterized in that the data packets additionally have a check digit value ( 47 ), wherein by means of the control circuit ( 17 ) is verifiable on the basis of a predetermined calculation scheme, whether a received data packet ( 41 ) contains a correct Prüfzifferwert, and wherein only in the case of a positive result of this review by the control circuit - an associated acknowledgment data packet to the sender of the received data packet can be sent, - the received data packet can be forwarded to another detector unit, and / or - received data packet in the detector unit is processable. Detector unit according to one of the preceding claims, characterized in that by means of the control circuit ( 17 ) is verifiable, whether within a predetermined time interval after sending a data packet ( 41 ) has been received an associated acknowledgment data packet, wherein in the case of a negative result of this review, the previously sent data packet is retransmitted by means of the control circuit. Detector unit according to one of the preceding claims, characterized in that the detector unit ( 11 ) on the first coupling side ( 13 ) and on the second coupling side ( 15 ) further comprises a respective separate synchronization port (INT) for receiving and outputting a detector synchronization signal, the synchronization ports being connected to the sensor section (13). 23 ) of the detector unit are connected. Detector unit according to one of the preceding claims, characterized in that the control circuit ( 17 ) for performing an address assignment operation, wherein after switching on the detector unit ( 11 ) is testable by the control circuit, whether at a predetermined coupling side ( 13 . 15 ) is coupled to a further unit, wherein in the case of a negative result of this test, the control circuit of the detector unit ( 11 ) assigns a predetermined address and at the other coupling side ( 15 respectively. 13 ) outputs a corresponding address signal, and in the case of a positive result of this test, the control circuit at the predetermined coupling side ( 13 . 15 ) receives an address signal, the detector unit ( 11 ) assigns an adjacent address and at the other coupling side ( 15 respectively. 13 ) outputs a corresponding address signal. Detector unit according to one of the preceding claims, characterized in that the control circuit ( 17 ) for processing neighbor addresses that are independent of an assigned current address of a detector unit and in addition to such a current address for each detector unit ( 11 ) always the two immediately adjacent detector units ( 11 ). Detector unit according to one of the preceding claims, characterized in that the detector unit ( 11 ) on the two coupling sides ( 13 . 15 ) each having a connecting portion, which is designed for direct coupling with an associated connecting portion of a similar detector unit. Detector unit according to one of the preceding claims, characterized in that the detector unit ( 11 ) on its first coupling side ( 13 ) with the second coupling side ( 15A a similar detector unit ( 11 ) and at its second coupling side with the first coupling side of a similar detector unit such that a data input (RxD) of a detector unit with a data output (TxD) of the other detector unit and a data output (TxD) of a detector unit with a data input (RxD ) is connected to the other detector unit. Detector unit according to one of the preceding claims, characterized in that the sensor section comprises a sensor ( 23 ), a part of a sensor or an optical, electronic or electrical interface to a sensor. Detector unit according to one of the preceding claims, characterized in that the detector unit ( 11 ) on the two coupling sides ( 13 . 15 Further, each having a power supply terminal (Vcc), wherein the two power supply terminals are directly connected to each other, and that the detector unit further comprises a ground terminal (GND) on the two coupling sides, wherein the two ground terminals are directly connected. Method for transmitting data between several detector units ( 11 ) of a detector system, wherein the detector units on a first coupling side ( 13 ) and on a second coupling side ( 15 ) each having at least one serial data input (RxD) and a serial data output (TxD), wherein the detector units are coupled in series such that the detector units on their respective first coupling side with the second coupling side of an adjacent detector unit and at its respective second coupling side with the first coupling side of an adjacent detector unit are connected, and wherein the data between the detector units in the form of data packets ( 41 ) and the data packets ( 41 ) of the detector units ( 11 ) are sent independently of a clock signal of a higher-order master unit, wherein the data packets ( 41 ) at least one recipient address ( 42 ), a sender address ( 43 ) and a command identifier ( 45 ) and a data packet ( 41 ) according to the recipient address contained therein ( 42 ) only on one coupling side ( 13 or 15 ), characterized that the data packets ( 41 ) have a constant length, that received or to be sent data packets ( 41 ) within the detector units ( 11 ) in a respective data packet memory ( 51 ), whereby the management of the data packets ( 41 ) Memory address pointers, each in a queue section ( 67 ) one of the respective first coupling side ( 13 ) associated transmit queue memory ( 55 ) or one of the respective second coupling side ( 15 ) associated transmit queue memory ( 57 ) and stored on a data packet ( 41 ) in the data packet memory ( 51 ) and that each memory address pointer is assigned a priority identifier which determines the order in which the data packet assigned to the memory address pointer (FIG. 41 ), whereby those data packets ( 41 ) receive the highest priority identifier which is present at one of the data inputs (RxD) of the detector unit ( 11 ) and according to the recipient address contained in the data packet ( 42 ) to another unit ( 11 ) should be forwarded. Method according to claim 23, characterized in that a detector unit ( 11 ) after receiving a data packet ( 41 ), according to the recipient address ( 42 ) was intended for this detector unit, sends an associated acknowledgment data packet to the sender of the received data packet. Method according to one of claims 23 to 24, characterized in that the data packets ( 41 ) only on one of the two coupling sides ( 13 . 15 ) of the sending detector unit ( 11 ), this coupling side being dependent on the recipient address ( 42 ) is selected. Method according to one of claims 23 to 25, characterized in that data packets ( 41 ) generated by a detector unit ( 11 ) on one of its two coupling sides ( 13 . 15 ) and according to recipient address ( 42 ) are intended for a different detector unit, on the respective other coupling side ( 15 respectively. 13 ) are returned unchanged. Method according to one of claims 23 to 26, characterized in that, starting from an outermost of the detector units coupled in series with each other ( 11 ) a detector synchronization signal is sent to the other detector units, which for the mutual synchronization of sensor sections ( 23 ) of the Detektoreinhei th is used and regardless of the data packets ( 41 ) is transmitted via separate synchronization ports (INT). Method according to one of claims 23 to 27, characterized in that by means of the data packets ( 41 ) Sensor data transmitted by a sensor ( 23 ) of the respective detector unit ( 11 ) assigned.