Communication system for serial communication between communication devices

Abstract

Communication system (100) for serial communication between a master communication device (101) and at least one slave communication device (103), wherein the master communication device (101) and the at least one slave communication device (103) are connected to each other for communication via a signal line (109), wherein the at least one slave communication device (103) has a unique identifier (105), wherein the master communication device (101) is configured to read at least a part of the unique identifier (105) via the signal line (109) and, on the basis of at least a part of the unique identifier (105), to assign an address (107) to the at least one slave communication device (103) and to transmit this address (107) to the slave communication device (103) via the signal line (109), characterized in that the unique identifier (105) is a string of characters formed from a plurality of characters.wherein the master communication device (101) is configured to query a specific character from the plurality of characters at a specific position in the character string by sending a query message (111) to the at least one slave communication device (103) via the signal line (109), wherein the specific position is shifted by one position in the character string in a subsequent query message.

Description

[0001] The present disclosure relates to a communication system for serial communication between communication devices, in particular for addressing communication devices.

[0002] Communication devices that form a communication system via a shared communication line are typically addressed so that messages can be sent between the devices via this shared line. This address is usually unique and can be predefined by one of the communication devices or assigned during the operation of the communication system. For address assignment during operation of the communication system, for example, a specific communication device is designed to control the address assignment process.

[0003] The purpose of this disclosure is to provide an efficient communication system that implements address assignment during the operation of the communication system.

[0004] This problem is solved by the features of the independent claims. Advantageous embodiments are the subject of the dependent claims, the description, and the accompanying figures.

[0005] The present disclosure is based on the finding that, in order to uniquely assign an address to a communication device in a communication network, a unique identifier of the communication device can be at least partially read out.

[0006] According to a first aspect, the disclosure relates to a communication system for serial communication between a master communication device and at least one slave communication device, wherein the master communication device and the at least one slave communication device are connected to each other for communication via a signal line, wherein the at least one slave communication device has a unique identifier, characterized in that the master communication device is configured to read at least a part of the unique identifier via the signal line and, on the basis of at least a part of the unique identifier, to assign an address to the at least one slave communication device and to transmit this address to the slave communication device via the signal line.

[0007] Assigning an address to a slave communication device in a communication system, particularly a local interconnect network (LIN), can be done manually, for example by setting a DIP switch, by hardwiring, or by one-time programming (OTP) in the slave communication devices. This can mean that assigning an address requires manual intervention during commissioning or maintenance of the communication system.

[0008] When replacing a primary slave communication device with a replacement communication device in a manually configured communication system, it may be necessary for the replacement communication device to have the same address as the primary communication device. Therefore, to ensure unique address assignment within the communication system, identical communication devices with different addresses may be required for the replacement process.

[0009] The address assignment according to the invention offers the advantage that no manual intervention is necessary for address assignment and / or that, after the replacement of a slave communication device in the communication network, the address assignment can be automatically re-implemented. This can advantageously reduce both manufacturing and maintenance costs.

[0010] In one embodiment, the communication system is a Local Interconnect Network (LIN), wherein the signal line is single-wire and the master communication device and the slave communication device are bidirectionally connected to each other via the signal line.

[0011] The respective address of the slave communication devices in the communication system, especially the LIN system, can be a Local Interconnect Network Identification (LIN ID).

[0012] Automatic address assignment to a slave communication device can be implemented using a Slave Node Position Detection (SNPD) method. Such a method can, for example, be a Bus Shunt Method (BSM) or a connection of the communication devices via an additional signal line, such as an Extra Wire Daisy Chain (XWDC). Both BSM and XWDC methods may require additional hardware and / or additional signal lines. The communication system according to the invention implements automatic addressing without additional hardware, particularly with regard to the LIN specification, without additional circuitry or signal lines.

[0013] Both BSM and XWDC may require at least one additional signal access in the slave communication devices, with BSM potentially requiring further additional circuitry in the slave communication devices.

[0014] The communication system can have a limited number of slave and / or master communication devices connected, meaning that only a limited number of unique identifiers can be implemented in the system. This allows for the unique identification and subsequent address assignment to a slave or master communication device using only a subset of the unique identifier string.

[0015] In one embodiment, the communication system is a LIN system that implements communication between an uninterruptible power supply (UPS) and a plurality of energy storage modules. The master communication device can be the UPS, and the at least one slave communication device can be formed by the plurality of energy storage modules.

[0016] In one embodiment, the unique identifier is a string of characters formed from a plurality of characters, wherein the master communication device is configured to query a specific character from the plurality of characters at a specific position in the string by sending a query message to the at least one slave communication device via the signal line.

[0017] The unique identifier of the slave communication devices can, for example, be a serial number of the respective slave communication device. In one embodiment, the serial number is a 64-bit binary string. The uniqueness of the identifier, particularly the serial number, ensures that the master communication device can uniquely identify each slave communication device. This advantageously enables, for example, the master communication device to uniquely address the slave communication devices.

[0018] In one embodiment, the at least one slave communication device is configured to process the query message of the master communication device and to confirm, by sending a reply message via the signal line, that the specific character is present at the specific position in the character string of the unique identifier of the slave communication device.

[0019] In one embodiment, the communication system has a plurality of slave communication devices and the master communication device is configured to recognize, based on the reply message received from the master communication device, whether a single slave communication device, no slave communication device, or more than one slave communication device of the plurality of slave communication devices has sent a reply message.

[0020] In one embodiment, the at least one slave communication device has a first operating state in which the at least one slave communication device is configured to send the reply message to the master communication device in response to the receipt of the query message from the master communication device.

[0021] In the first operating state, at least one slave communication device is not assigned an address, in particular a network address.

[0022] In one embodiment, the at least one slave communication device has, in addition to the first operating state, a second operating state, in particular a quiet mode. In the second operating state, the at least one slave communication device is configured to refrain from sending a reply message to the master communication device upon receiving the query message from the master communication device. In the second operating state, the at least one slave communication device is, for example, not assigned an address, in particular a network address.

[0023] In one embodiment, the at least one slave communication device has, in addition to the first and second operating states, a third operating state in which an address is assigned to the at least one slave communication device. In the third operating state, the at least one slave communication device is configured to refrain from sending a reply message to the master communication device upon receiving the query message from the master communication device.

[0024] In one embodiment, the at least one slave communication device has a first operating state, a second operating state, and a third operating state and is configured to send the reply message in response to the query message of the master communication device in the first operating state, in particular only in the first operating state, and to not send a reply message in response to the query message of the master communication device in the second and third operating states, or to refrain from sending the reply message, wherein an address is assigned to the at least one slave communication device in the third operating state.

[0025] In one embodiment, the master communication device is configured to put the at least one slave communication device into the first operating state, the second operating state, or the third operating state by sending a status message via the signal line.

[0026] If at least one slave communication device is in the first operating state, it can be switched to the second operating state by receiving the status message. Conversely, if at least one slave communication device is in the second operating state, it can be switched back to the first operating state by receiving the status message from the second operating state.

[0027] In one embodiment, the master communication device is configured to cause a restart of the at least one slave communication device by sending a restart message via the signal line, wherein the restart deletes the address in the at least one slave communication device and moves the at least one slave communication device from the third operating state to the first operating state.

[0028] From a received message, particularly a query, response, status, or restart message, the address field is read by the master and / or slave communication devices. This field contains an address and / or other data before further message content is processed. This allows the content of the address field to be used to trigger asynchronous, global services directed to all master and / or slave communication devices. Such services include, for example, a global restart (reset) of the master and / or slave communication devices, whereby all master and / or slave communication devices in the communication system are placed in a state corresponding to their state after initial power-up.

[0029] Another global service is querying a specific character at a specific position in the string of the unique identifier of the master and / or slave communication devices.

[0030] In one embodiment, the unique identifier is an unchangeable binary identifier.

[0031] Reading the unique identifier of at least one slave communication device by the master communication device can be achieved, for example, by querying the same character at different positions. If the unique identifier is implemented as a binary string, the query can, for instance, check whether a 1 is present at a specific position within the unique identifier. This specific position may be shifted by one position in the string in subsequent queries. Similarly, a service that checks for a zero at a specific position within the unique identifier can be implemented.

[0032] According to a second aspect, the disclosure relates to a method for serial communication between a master communication device and at least one slave communication device, wherein the master communication device and the at least one slave communication device are connected to each other for communication via a signal line, wherein the at least one slave communication device has a unique identifier, with reading at least a part of the unique identifier of the slave communication device via the signal line; assigning an address to the at least one slave communication device based on at least a part of the unique identifier; and transmitting this address to the slave communication device via the signal line.

[0033] In one embodiment, the method further comprises: sending a restart message by the master communication device via the signal line to the at least one slave communication device, such that the address assigned to the at least one slave communication device is deleted and the at least one slave communication device is switched from the third operating state to the first operating state.

[0034] If at least one slave communication device is in the second operating state, it can be switched from the second operating state to the first operating state by receiving the restart message.

[0035] In one embodiment, the method further comprises: sending a query message by the master communication device via the signal line to the at least one slave communication device, which contains a character and the query position of the character in the string of the unique identifier;

[0036] Sending a reply message by the at least one slave communication device via the signal line to the master communication device if the received character matches the unique identifier character at the received query position in the unique identifier string;

[0037] Sending a status message by the master communication device via the signal line to all slave communication devices that have not sent a reply message to the query message, whereby the status message causes these slave communication devices to enter sleep mode and no longer respond to messages from the master communication device;

[0038] Repeat the preceding procedure steps with another character at another query position until only a single slave communication device or no slave communication device sends a response message to the master communication device;

[0039] Determining by the master communication device that no slave communication device has sent a reply message after a predetermined time, so that the preceding procedural steps are repeated without sending the restart message with another character at another position in the string, as long as not all positions of the string have been queried;

[0040] Assigning an address by the master communication device to the slave communication device if only this one slave communication device responds, wherein this slave communication device is in the third operating state and does not participate in the further procedure and is optionally in the third operating state;

[0041] Repeat the preceding procedural steps without deleting the assigned addresses and without the participation of those slave communication devices to which an address has already been assigned, until each of the slave communication devices has been assigned an address.

[0042] In one embodiment, the method further includes terminating the method if all positions have been queried and no slave communication device has responded during this time, particularly during the query, because an address has been assigned to all slave communication devices and all slave communication devices have been placed in the third operating state.

[0043] In one embodiment, all messages are transmitted digitally and consist of 8 bytes of user data and a 1-byte checksum.

[0044] In one embodiment, the master communication device is configured to determine, based on the checksum, whether a slave communication device or a plurality of slave communication devices has sent a reply message.

[0045] According to a third aspect, the disclosure relates to a computer program with program code for executing the aforementioned procedure, if the program code is executed on a processor.

[0046] Further examples are explained with reference to the accompanying figures. These show: Fig. 1 a communication system according to an embodiment, Fig. 2 a communication method according to an embodiment, Fig. 3 a signal sequence of a message in the signal line according to an embodiment, Fig. 4 a communication method according to one embodiment.

[0047] Fig. Figure 1 shows a schematic representation of a communication system 100 for serial communication between the master communication device 101 and at least one slave communication device 103 , where the master communication device 101 and at least one slave communication device 103 for communication via a signal line 109 are interconnected, with at least one slave communication device 103 a unique identifier 105 exhibits. In Fig. 1 are three examples of slave communication devices 103 The master communication device is shown. 101 is trained to use the signal line 109 at least part of the unique identifier 105 to read and, based on at least part of the unique identifier 105 the at least one slave communication device 103 an address 107to assign and this address 107 via the signal line 109 to the slave communication device 103 to be transmitted. The address 107 can be in an address field of the slave communication device 103 be saved.

[0048] The communication system 100 can be a Local Interconnect Network (LIN), where the signal line 109 It can be configured as a single wire and the master communication device 101 and the slave communication device 103 bidirectional via the signal line 109 can be interconnected.

[0049] Fig. Figure 2 shows a schematic representation of a procedure. 200 for serial communication between the master communication device 101 and at least one slave communication device 103 , where the master communication device 101 and at least one slave communication device 103for communication via the signal line 109 are interconnected, with at least one slave communication device 103 a unique identifier 105 exhibits, with the following steps: Reading out at least part of the unique identifier 105 of the slave communication device 103 via the signal line 109 , Assigning an address 107 to which at least one slave communication device 103 based on at least part of the unique identifier 105 and transmitting this address 107 via the signal line 109 to the slave communication device 103 .

[0050] Fig. Figure 3 schematically shows the signal sequence of a message in the signal line. 109 according to one embodiment.

[0051] The messages sent by the master and / or slave communication devices 101 , 103via the signal line 109 Messages that can be sent can be implemented according to ISO / OSI levels 1 and 2 of the LIN standard, revision 2.1. Up to 8 bytes of payload data can be transmitted in a single message, within a protocol frame. 300 are embedded. Such a protocol framework 300 consists of - a break field 301 , which has a low signal level and a time length of at least 13 bits; - a sync field 303 , which transmits the string 0×55 (0b01010101) to realize the synchronization of a receiving circuit in the master and / or slave communication devices, in particular a phase-locked loop (PLL); - a Protected ID field (PID), which stores the address on the last 6 bits 107 of the master and / or slave communication device 101 , 103contains the address intended as the recipient of the message, allowing a maximum of 64 master and / or slave communication devices to be addressed (the remaining front 2 bits contain parity information to ensure that the address 107 was transmitted without errors); - a data field 307 , which contains up to 8 bytes of user data; - Checksum 309 , which is a 1-byte checksum entry in the data field 307 contained bytes.

[0052] According to the LIN standard, addresses 60 (0×3C) to 63 (0×3F) can be used for protocol-internal purposes, leaving addresses 0 to 59 available for addressing the master and / or slave communication devices. 101 , 103 can be used. Therefore, a total of 60 master and / or slave communication devices can be used. 101 , 103 in the LIN system 100 be clearly addressed.

[0053] In one embodiment, an address assignment to the at least one slave communication device is possible. 103 in the communication system 100 , in particular a LIN system, without additional circuitry or signal access. This offers the advantage that address assignment to the master and / or slave communication devices is straightforward. 101 , 103 It can be implemented in a particularly user-friendly and manufacturing-efficient manner, especially automatically.

[0054] Fig. Figure 4 schematically shows a block diagram of the procedure for serial communication between the master communication device. 101 and at least one slave communication device 103 according to one embodiment. The master communication device 101 and at least one slave communication device 103send messages, in particular query, reply and / or status messages, to the at least one slave communication device 103 an address 107 based on the respective unique identifier 105 the slave communication devices 103 to assign.

[0055] A received message is processed by the master and / or slave communication devices. 101 , 103 the address 107 The address is read before further message content is processed. 107 can be used to trigger asynchronous, global communications to all master and / or slave communication devices 101 , 103 targeted services are used.

[0056] According to one embodiment, querying a specific character at a specific position in the string of the unique identifier 105 the master and / or slave communication devices 101 , 103a global service. The aforementioned global services can be provided by the master and / or slave communication devices. 101 , 103 immediately after switching on the master and / or slave communication devices 101 , 103 be understood.

[0057] According to the in Fig. In the embodiment shown in Figure 4, this query is implemented by querying the same character at different positions. The unique identifier 105 is implemented as a binary string, so the query checks whether a 1 is present at a specific position in the unique identifier. 105 of the respective master and / or slave communication device 101 , 103 is present. The specified position may be shifted by one position in the string in subsequent queries and can be associated with the first position of the unique identifier. 105 start.

[0058] The following describes the address allocation process, which uses the aforementioned global service to query a 1 at a predetermined position in the unique identifier string. 105 uses which is binary in at least one slave communication device 103 is stored. The master communication device 101 sends a query message to all slave communication devices 103 , where the query message is an Ask-for-one message containing a specific position with which the master communication device 101 queries whether the unique identifier is present at the specific position in the string 105 A 1 is present. The master communication device 101 It sends the first message after the restart. 401 an Ask-for-one message that checks if the first position in the string contains the unique identifier 105A 1 is present. Subsequent Ask-for-one messages from the master communication device. 101 sequentially query the positions of the string containing the unique identifier that follow the first position. 105 away.

[0059] Does the master communication device transmit 101 When an Ask-for-one message is sent, one of the following three possible states occurs:

[0060] None of the majority of slave communication devices 103 The position queried shows a 1, so there is no slave communication device. 103 sends a reply message. The master communication device 101 After a certain time (time-out), it sends another query message with a subsequent position.

[0061] Exactly one slave communication device 103 the majority of slave communication devices 103 The queried position shows a 1, so this slave communication device 103a reply message is sent. The master then sends an address assignment message, which specifies the address to be assigned. 107 for example in the Protected ID Field (PID) and the unique identifier 105 in the data field, where the address assignment message is contained according to the in Fig. The embodiment described in section 3 is formed. This consists of exactly one slave communication device. 103 The address is saved after receiving this message. 107 in the address field of the exactly one slave communication device 103 and responds to the following query messages from the master communication device 101 no longer.

[0062] A number of slave communication devices 103 the majority of slave communication devices 103 The queried position shows a 1, indicating that this number of slave communication devices 103 sends a reply message. The signal line 109exhibits zero dominance, so the response messages of the number of slave communication devices 103 A defective message is generated. The defective message has an incorrect checksum that cannot be associated with the message content. This incorrect checksum is generated by the master communication device. 101 evaluated so that the master communication device 101 detects that a number of slave communication devices 103 the majority of slave communication devices 103 has sent a reply message.

[0063] A further number of slave communication devices 103 the majority of slave communication devices 103 , which responds to the Ask-for-one message from the master communication device 101 If the device has not responded and therefore shows a 0 at the query position, it will be processed by the master communication device. 101put into the second operating state, so that the remaining number of slave communication devices 103 subsequent query messages from the master communication device 101 no longer responds. The second operating state of at least one slave communication device. 103 This could be, in particular, a quiet mode.

[0064] The quiet mode of the slave communication device 103 is switched via one or two bits in the byte, which according to the in Fig. 3. The embodiment shown also contains the 6 bits which represent the query position of the unique identifier. 105 include.

[0065] Was all slave communication devices 103 an address 107 Once assigned, no further slave communication device will be sent in a subsequent pass of the procedure. 103A reply message is sent, and the process terminates after a specific time (time-out). This final process run also ensures that any slave communication devices not addressed due to transmission errors are not flagged. 103 Now you can send and receive a reply message. Reference symbol list 100 communication systems 101 Master Communication Device 103 Slave communication device 105 unique identifiers 107 Address 109 Signal line 111 Query message 113 Reply message 200 procedures 300 protocol frames 301 Break-Field 303 Sync-Field 305 PID field 307 Data Field 309 Checksum 401 Restart Message

Claims

[1] Communication system (100) for serial communication between a master communication device (101) and at least one slave communication device (103), wherein the master communication device (101) and the at least one slave communication device (103) are connected to each other for communication via a signal line (109), wherein the at least one slave communication device (103) has a unique identifier (105), characterized by , that the master communication device (101) is configured to read at least part of the unique identifier (105) via the signal line (109) and, on the basis of at least part of the unique identifier (105), to assign an address (107) to the at least one slave communication device (103) and to transmit this address (107) to the slave communication device (103) via the signal line (109). [2] Communication system (100) according to claim 1, wherein the communication system (100) is a Local Interconnect Network (LIN), wherein the signal line (109) is single-wire and the master communication device (101) and the slave communication device (103) are bidirectionally connected to each other via the signal line (109). [3] Communication system (100) according to one of the preceding claims, wherein the unique identifier (105) is a string of characters formed from a plurality of characters, wherein the master communication device (101) is configured to query a specific character of the plurality of characters at a specific position in the string by sending a query message (111) to the at least one slave communication device (103) via the signal line (109). [4] Communication system (100) according to claim 3, wherein the at least one slave communication device (103) is configured to process the query message (111) of the master communication device (101) and to confirm, by sending a reply message (113) via the signal line (109), that the specific character is present at the specific position in the character string of the unique identifier (105) of the slave communication device (103). [5] Communication system (100) according to claim 4, wherein the communication system (100) comprises a plurality of slave communication devices (103) and the master communication device (101) is configured to recognize, based on the reply message (113) received by the master communication device (101), whether a single slave communication device (103), no slave communication device (103), or more than one slave communication device (103) of the plurality of slave communication devices (103) has sent a reply message (113). [6] Communication system (100) according to claim 4, wherein the at least one slave communication device (103) has a first operating state, a second operating state and a third operating state and is configured to send the reply message (113) in response to the query message (111) of the master communication device (101) in the first operating state, in particular only in the first operating state, and not to send a reply message (113) in response to the query message (111) of the master communication device (101) in the second and third operating states, or to refrain from sending the reply message (113), wherein an address (107) is assigned to the at least one slave communication device (103) in the third operating state. [7] Communication system (100) according to claim 6, wherein the master communication device (101) is configured to put the at least one slave communication device (103) into the first operating state, the second operating state or the third operating state by sending a status message via the signal line (109). [8] Communication system (100) according to claim 6 or 7, wherein the master communication device (101) is configured to cause a restart of the at least one slave communication device (103) by sending a restart message (401) via the signal line (109), wherein the restart deletes the address (107) in the at least one slave communication device (103) and moves the at least one slave communication device (103) from the third operating state to the first operating state. [9] Communication system (100) according to one of the preceding claims, wherein the unique identifier (105) is an unchangeable binary identifier. [10] Method (200) for serial communication between a master communication device (101) and at least one slave communication device (103), wherein the master communication device (101) and the at least one slave communication device (103) are connected to each other for communication via a signal line (109), wherein the at least one slave communication device (103) has a unique identifier (105) with: Reading at least part of the unique identifier (105) of the slave communication device (103) via the signal line (109); Assigning an address (107) to the at least one slave communication device (103) based on at least a part of the unique identifier (105); and Transmit this address (107) via the signal line (109) to the slave communication device (103). [11] Method (200) according to claim 10, wherein the method (200) further comprises: Sending a restart message (401) by the master communication device (101) via the signal line (109) to the at least one slave communication device (103), so that the address (107) assigned to the at least one slave communication device (103) is deleted and the at least one slave communication device (103) is switched from the third operating state to the first operating state. [12] Method (200) according to claim 10 or 11, wherein the method (200) further comprises: Sending a query message (111) by the master communication device (101) via the signal line (109) to the at least one slave communication device (103), which contains a character and the query position of the character in the string of the unique identifier (105); Sending a reply message (113) by the at least one slave communication device (103) via the signal line (109) to the master communication device (101) if the received character matches the unique identifier character (105) at the received query position in the unique identifier string (105); Sending a status message by the master communication device (101) via the signal line (109) to all slave communication devices that have not sent a reply message (113) to the query message (111), the status message causing these slave communication devices (103) to enter sleep mode and no longer respond to messages from the master communication device (101); Repeat the preceding procedure steps with another character at another query position until only a single slave communication device (103) or no slave communication device (103) sends a reply message (113) to the master communication device (101); Determining by the master communication device (101) that after a predetermined time no slave communication device (103) has sent a reply message (113), so that the preceding procedural steps are repeated without sending the restart message (401) with another character at another position in the string, as long as not all positions of the string have been queried; Assigning an address (107) by the master communication device (101) to the slave communication device (103) if only this one slave communication device (103) responds, wherein this slave communication device (103) does not participate in the further procedure, and in particular is in a third operating state; and Repeating the preceding procedure steps without deleting the assigned addresses (107) and without the participation of those slave communication devices (103) to which an address (107) has already been assigned, until each of the slave communication devices (103) has been assigned an address (107). [13] Method (200) according to any one of claims 10 to 12 above, wherein the method (200) further comprises: Termination of the procedure (200) if all positions have been queried and no slave communication device (103) has responded during the query, since all slave communication devices (103) have been assigned an address (107) and all slave communication devices (103) are in the third operating state. [14] Method (200) according to any one of the preceding claims 10 to 13, wherein all messages are transmitted digitally and have 8 bytes of user data and a 1 byte checksum. [15] Method (200) according to any one of the preceding claims 10 to 14, wherein the master communication device (101) is configured to determine, on the basis of the checksum, whether a slave communication device (103) or a plurality of slave communication devices (103) has sent a reply message (113). [16] Computer program comprising program code for executing the method (200) according to any one of claims 10 to 15, when the program code is executed on a processor.

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