WO2011012041A1

WO2011012041A1 - System and mothod for setting addresses of serial bus slave devices

Info

Publication number: WO2011012041A1
Application number: PCT/CN2010/075001
Authority: WO
Inventors: 周保航; 刘明明; 孟燕妮; 韦树旺
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-07-28
Filing date: 2010-07-06
Publication date: 2011-02-03
Also published as: CN101630298B; CN101630298A

Abstract

A system for setting addresses of serial bus slave devices is disclosed. The system comprises: a master device located in one end of the serial bus; a plurality of slave devices connected with the master device via the serial bus for setting their own addresses according to set information from the master; and a plurality of switches controlled by corresponding slave devices. Each switch corresponds to each of a plurality of slave devices, and is located behind the corresponding slave device along the serial bus. Each of the plurality of slave devices switches off a corresponding switch responding to an initialization setting instruction from the master device, and switches on the corresponding switch responding to an effective address signal from the master device. A method for setting addresses of serial bus slave devices is also disclosed. The technical solution can set addresses of serial bus slave devices automatically and sequentially.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of bus communication, and more particularly to a serial bus slave address setting system and method. BACKGROUND OF THE INVENTION With the development of technology, in the fields of industrial control, communication, automobile, consumer electronics and the like, embedded controllers and serial master-slave buses are widely used. A master-slave serial bus is a device or unit that shares a bus in a product or system, and monitors and controls multiple slave devices (or units) through one master device (or unit). Each slave (unit) has its own core processing unit that can operate independently and perform the same or different functions. Since a bus is shared, each slave device must have its own unique address to achieve normal communication functions. It is especially important to obtain the address of the device itself. The current method for setting the slave address has the following method: A unique address is set from the device unit itself via software or hardware. This method can be applied when the slave devices are different from each other; however, when there are multiple identical slave devices, it is completely unsuitable. Manually set the address, that is, manually set a different address for each slave device when the entire system or product is initially running, which may cause additional setup workload and is prone to setup errors. On the system, there are different dialing or jumper settings at the interface corresponding to each slave device. After the slave device is plugged into the system, read the status of these dials or jumpers to obtain their own address. This makes the production of the system more cumbersome, and the interface between the device and the system is complicated. Each slave device has its own address line connected to the master device, and the slave device is strobed through the address line. This causes a lot of address lines at the master device, which is not suitable for systems with more slave devices. The invention provides a simple and reliable serial master-slave bus structure. By adding a small amount of hardware and signals, combined with the following setting method, the automatic order setting of the slave device addresses can be realized. SUMMARY OF THE INVENTION In order to achieve automatic sequence setting of slave device addresses, the present invention proposes a serial bus slave device address setting system: comprising: a master device, disposed at one end of a serial bus, for setting an address for a slave device; Slave devices are respectively connected to the master device via a serial bus; and a plurality of switches, wherein each switch corresponds to each slave device of the plurality of slave devices, and is disposed along the serial bus after the corresponding slave device And for accepting corresponding slave device control, wherein each of the plurality of slave devices is configured to control the corresponding switch to be in an off state in response to an initialization setting instruction from the master device, and configured to respond to the effective from the master device The signal of the address controls the corresponding switch to be in an on state. Wherein each of the plurality of slave devices comprises: a transceiver unit, configured to receive an initialization setting instruction from the master device via the serial bus and/or a signal for receiving an effective address from the master device via the serial bus The switch control unit is configured to control the corresponding switch to be in an off state according to the initial setting instruction, and to be used in the on state corresponding to the effective address control. The other end of the serial bus is provided with a bus state monitoring unit for monitoring the on/off state of the serial bus, wherein when the signal sent by the master device is not received, it is used to determine that the serial bus is in an off state. When receiving a signal from the master device, it is used to determine that the serial bus is in the on state. Wherein, both ends of the serial bus are connected into a loop by connecting a connection line with an emergency switch, wherein when the serial bus is in an off state, the emergency switch is turned on. Among them, the plurality of switches are normally closed switches, and the emergency switches are normally open switches. Wherein each of the plurality of slave devices is further configured to initialize its own address in response to an initialization setting instruction from the master device. The master device stores not less than the effective addresses of the plurality of slave devices that are different from each other. The master device sequentially sends the effective address through the serial bus. The interval time T at which the master device sends the effective address is not less than the time required for the switch to perform the conduction action. The valid address signal is the first address signal received by each of the plurality of slave devices from the master device. In order to realize the automatic sequence setting of the slave device address, the present invention proposes a serial bus slave device address setting method, the method comprising: the slave device controls the corresponding switch of the slave device to be in an open state in response to an initialization setting instruction from the master device. And/or the slave device controls its own corresponding switch to be in a conducting state in response to a signal from the active address of the master device. The beneficial effects of the present invention are as follows:

1) By adding the address setting switch, the order of the slave device addresses can be automatically set; and, regardless of the number of devices and the physical location (the number of devices may be less than the number of nodes, the physical locations may not be sequentially arranged; ), the addresses of the slave devices are all sequential. The slave device address is set in order, making the fault at the on-site inspection clear from the location of the device. 2) Since there is a bus status monitoring unit inside the main device, the bus status can be monitored and the self-diagnosis function can be realized. At the same time, the number of online slave devices can be automatically counted.

3) The presence of the emergency switch in the main equipment can cope with the bus disconnection fault, realize the automatic processing of the fault, and greatly improve the reliability of the communication. In summary, with the serial bus structure and method of the present invention, the slave address setting can be completed automatically and sequentially. The bus structure is simple, the number of added devices is small; the setting method is simple and reliable; the efficiency of device address setting can be improved, the efficiency of product production and maintenance can be improved, the probability of address setting error can be reduced; and the reliability of communication can be improved. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawings: FIG. 1 is a schematic diagram showing the physical structure of a serial bus according to the present invention; FIG. 2 is a first schematic diagram showing a bus change when a device address is sequentially arranged according to an exemplary embodiment of the present invention; FIG. 4 is a schematic diagram of a bus change when the slave device address is sequentially set; FIG. 4 is a bus change when the slave device address is sequentially set according to an exemplary embodiment of the present invention. FIG. 3 is a schematic diagram 4 of a bus change when the device address is sequentially set according to an exemplary embodiment of the present invention; FIG. 6 is a first schematic diagram of emergency processing when a bus fault occurs in an exemplary embodiment of the present invention; FIG. 2 is a schematic diagram of emergency handling in the event of a bus failure of an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION The present invention provides a simple and effective serial bus structure. For this structure, a method for automatically setting the slave device addresses is proposed, which can realize the automatic slave address of the master-slave serial bus. Setting; At the same time, it can also monitor the bus status, realize the automatic processing of faults, and greatly improve the reliability of communication. Through this simple structure and method, the automatic order setting of the slave device address is realized, the efficiency of production and maintenance is improved, the probability of misconfiguration is reduced, and the reliability of communication is improved. The following description will be made in conjunction with the accompanying drawings. The entire structure of the present invention includes: a master device (including a bus state listening unit), a slave device, a ring serial bus, and a slave address setting switch. The entire serial bus structure is shown in Figure 1, where:

1) The master device has only one in the system, and the part of the master device connected to the serial bus includes two units: a main transceiver unit and a bus state monitoring unit; the main transceiver unit is used for communication with the slave device, and completes Device control, status detection and address setting are located at the head end of the serial bus; the bus status monitoring unit is used to monitor the status of the serial bus, contains only one receiving unit, can receive data on the bus, can not send data, and the bus The ends are connected. Inside the main unit is an emergency switch (K in Figure 1), which is a normally open switch that connects the head end and end of the bus together to form a bus loop.

2) There may be more than one slave device, which is a unit with independent functions in the system; the slave device is directly connected to the bus, and each slave device is connected to the serial bus also includes two units: communication transceiver unit, complete from The communication function between the device and the system; the switch control unit for controlling the switches connected in series on the bus, each slave device can only control the switch located behind the node connected to the serial bus. For example, the 2# slave device in the figure can only control the K2 switch in the bus. The interface from the device to the bus is uniform and simple, only the bus interface and the address setting switch control interface. 3) The address setting switch is serially connected to the serial bus, the number of which is corresponding to the number of nodes on the bus that can be connected to the slave device; its position is located behind each node, and the node is located The slave device connected to it is controlled. The switch is a normally closed switch (normally closed) that disconnects the portion of the bus that follows the node from the bus. 4) A master-slave serial bus, the head end of which is connected to the main transceiver unit of the master device, and the end is connected to the bus state monitoring unit of the master device; the middle includes a plurality of nodes, and each node can be connected to a slave device; After the nodes are connected in series with an address setting switch, each node portion can be divided into isolated intervals. The method of setting the slave device address will be specifically described below. 1) Step 1: Start slave address setting Before the device address setting is triggered, the master bus status monitor unit detects the bus status: Under normal conditions, all switches on the serial bus remain closed, and the serial bus is connected. At this time, the data sent by the main transceiver unit can be received. In an abnormal situation, if the main device bus state monitoring unit does not receive the data sent by the main device main transceiver unit, the bus may have a disconnection point, give an abnormal alarm, and perform emergency response processing. The bus state at this time is shown in Figure 1. After triggering from the device address setting, the main transceiver unit sends a broadcast command for setting the address to all the slave devices on the bus. After receiving the command correctly, all the slave devices clear their own device address to "0"; The control unit controls the switching action. The bus state at this time is shown in Figure 2. At this time, only the 1# slave device and the master device are connected.

2) Step 2: Set 1# slave device master device main transceiver unit to send 1# slave device address setting command. At this time, only 1# device communicates with the master device. After the 1# device receives the command correctly, it will itself. Change the address to " Γ and send a confirmation command to the master device, and control the switch to close (the K1 switch in the figure is closed). At this point, the 2# slave device is connected to the bus, as shown in Figure 3.

3) Step 3: Set 2#~N# slave device address in Figure 3, 1# slave device, 2# slave device is connected to master device, 1# slave device address is "Γ, 2# The slave device address is "0"; the master device master transceiver unit sends the 2# slave device address setting command, the 2# slave device address changes its own address to "2", and sends a confirmation command to the master device, and the control switch is closed ( The K2 switch in the figure is closed). At this point, the 3# slave device is connected to the bus, as shown in Figure 4. Repeat the above operation to complete the 3#~N# slave device address setting. After the N# slave device address is set, send a confirmation command to the master device and control the switch to close (the KN switch in the figure is closed), as shown in Figure 5.

4) Step 4: Complete the slave device address setting The master device sends the slave device address setting command again, and the bus state monitoring unit receives the address setting command. At this time, all slave device address settings are completed, and the master device records the number of slave devices. Reliability strategy: During system operation, the bus status monitoring unit in the master monitors the status of the entire bus, in the event of a disconnection somewhere on the serial bus (such as a disconnection at the bus connection or an address caused by a slave device failure) When the setting switch is turned off, the bus status monitoring unit will not receive the data of the main sending unit, and the main device will recognize that the bus has a disconnection fault and will enter the communication emergency processing mode. At this time, the main device will close the emergency switch (as shown in the figure). , turns the bus into a ring to deal with bus disconnection failures. When a disconnection occurs on the bus (for example, K2 is abnormally disconnected as shown in Figure 6), the communication emergency mode processing can completely restore the communication of the entire network, and the entire network is still connected; when multiple disconnections occur ( For example, A and K2 are disconnected as shown in Fig. 7. It is also possible to limit the failure of the communication to a certain range (the area between A and K2); thereby greatly improving the reliability of communication. Problems in actual use:

1) The switch in the bus structure is the key device for address setting. It needs to be selected as the normally closed type to ensure that the bus is connected when the slave device is not plugged into the system.

2) When setting the slave address, you need to consider the time of the switch action, do a good time delay, try to select a fast switch to improve the efficiency of the address setting. The implementation of the technical solution is further described in detail below with reference to the accompanying drawings and specific embodiments. For example, a communication combined power supply system is configured with six intelligent rectifier modules, and one monitoring unit is configured, and the monitoring unit is configured to detect and control six intelligent rectifier modules. , using RS485 network between them Communication. In this way, the monitoring unit is the master device and the six rectifier modules are the slave devices. The specific address setting process is as follows:

1) After the monitoring unit is powered on, the monitoring unit determines whether the bus is normal by sending a test command. If the bus status monitoring unit in the monitoring unit can receive the test command, the bus is normal, otherwise it is abnormal;

2) After confirming that the bus is correct, the monitoring unit sends a broadcast command for the address setting. After each rectifier module receives the command, the rectifier module changes its own address to "0" and controls its corresponding switching action.

3) After the delay time T (T is greater than the action time of the switch), the monitoring unit sends a command to set the address to "1" to the "0" address rectifier. At this time, only the 1# rectifier can receive the command, which will itself The address is changed to "1" and a confirmation command is sent to the monitoring unit, and the control switch returns to the normal state.

4) After receiving the " Γ address setting successful confirmation, and then waiting for T time, the monitoring unit sends a command to set the address to "2" to the "0" address rectifier. At this time, only the address of the 2# rectifier is "0", 2 # rectifier After receiving the command, change its own address to "2", and send a confirmation command to the monitoring unit, and the control switch returns to the normal state.

5) Repeat the above operation, each time the monitoring unit resets the address to the "0" address rectifier. Each time the address is set, the address to be sent is incremented by one to complete the setting of the six rectifier addresses. When the monitoring unit issues a command to set the address to the "0" address rectifier again, the bus status monitoring unit of the monitoring unit receives this command. The monitoring unit completes the address setting process and records the number of slave devices (6). This completes the address sequence setting of the rectifier, and the address of each rectifier corresponds to its position in the system. The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A serial bus slave address setting system, comprising:

a master device disposed at one end of the serial bus for setting an address for the slave device; a plurality of slave devices connected to the master device via the serial bus; and a plurality of switches, wherein each switch Each of the plurality of slave devices corresponds to, and is disposed along the serial bus respectively after the corresponding slave device, and is controlled by the slave device corresponding thereto,

Wherein each of the plurality of slave devices is configured to control a corresponding switch to be in an open state in response to an initialization setting instruction from the master device, and to respond to a signal from the active address of the master device. Controlling the corresponding switch to be in an on state.

2. The system according to claim 1, wherein each of the plurality of slave devices comprises:

a transceiver unit for receiving, by the serial bus, the initialization setting instruction from the master device and/or a signal for receiving an effective address from the master device via the serial bus;

And a switch control unit, configured to control the corresponding switch to be in an off state according to the initial setting instruction, and to control the corresponding switch to be in an on state according to the effective address.

The system according to claim 1, wherein the other end of the serial bus is provided with a bus state monitoring unit for monitoring an on/off state of the serial bus, wherein, when not received The signal sent by the master device is used to determine that the serial bus is in an off state, and is used to determine that the serial bus is in an on state when receiving a signal from the master device.

4. The system according to claim 3, wherein both ends of the serial bus are connected in a loop by a connection line connected with an emergency switch, wherein when the serial bus is in an off state When the emergency switch is turned on.

The system according to any one of claims 1 to 4, wherein the plurality of switches are normally closed switches, and the emergency switch is a normally open switch.

6. The system of claim 1, wherein each of the plurality of slave devices is further for initializing its own address in response to an initialization setting instruction from the master device.

The system according to claim 1, wherein the master device stores not less than the effective addresses of the plurality of slave devices that are different from each other.

8. The system according to claim 7, wherein the master device sequentially transmits the effective address through the serial bus.

9. The system according to claim 8, wherein the interval T during which the master transmits the effective address is not less than a time required for the switch to perform an on action.

10. The system of claim 1 wherein the signal of the effective address is a first address signal received by the slave device from the master device.

A serial bus slave address setting method, comprising:

The slave device controls its own corresponding switch to be in an open state in response to an initialization setting command from the master device; and/or

The slave device controls the self-corresponding switch to be in an on state in response to a signal from the active address of the master device.