阅读说明：本技术 一种通讯组件及通讯系统 (Communication assembly and communication system ) 是由 秦英林 张玉良 余杰 于 2020-03-23 设计创作，主要内容包括：本发明公开了一种通讯组件,包括主控芯片、485芯片、保护电容及传输总线；所述主控芯片连接至所述485芯片的OE端,所述485芯片通过所述485芯片的A端、B端连接至所述传输总线；所述主控芯片与所述OE端之间设置有所述保护电容,其中,所述保护电容靠近所述主控芯片的极板为主控极板,所述保护电容靠近所述OE端的极板为OE极板；所述OE极板接公共端；所述OE极板与所述公共端之间,包括充电电阻。本发明通过在连通所述主控芯片与所述485芯片的OE端的连接通路上加装了所述保护电容,使避免了所述485芯片由于前端故障引起的持续发送冗余信息导致锁死,本发明提供的技术方案结构简单工艺难度低。本发明同时还提供了一种具有上述有益效果的通讯系统。(The invention discloses a communication assembly, which comprises a main control chip, a 485 chip, a protection capacitor and a transmission bus, wherein the main control chip is connected with the 485 chip through the protection capacitor; the master control chip is connected to the OE end of the 485 chip, and the 485 chip is connected to the transmission bus through the A end and the B end of the 485 chip; the protection capacitor is arranged between the main control chip and the OE end, wherein a polar plate of the protection capacitor close to the main control chip is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate; the OE pole plate is connected with the public end; and a charging resistor is arranged between the OE polar plate and the common terminal. According to the invention, the protection capacitor is additionally arranged on the connecting passage of the OE end which is communicated with the main control chip and the 485 chip, so that the 485 chip is prevented from being locked due to continuous sending of redundant information caused by the failure of the front end. The invention also provides a communication system with the beneficial effects.)

1. A communication assembly is characterized by comprising a main control chip, a 485 chip, a protection capacitor and a transmission bus;

the master control chip is connected to the OE end of the 485 chip, and the 485 chip is connected to the transmission bus through the A end and the B end of the 485 chip;

the protection capacitor is arranged between the main control chip and the OE end, wherein a polar plate of the protection capacitor close to the main control chip is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate;

the OE pole plate is connected with the public end; and a charging resistor is arranged between the OE polar plate and the common terminal.

2. The communication assembly of claim 1, wherein a unidirectional conducting circuit is included between the OE plate and the common terminal in parallel with the charging resistor;

the one-way conduction circuit can pass current from the OE pole plate to the public end, and the resistance value of the one-way conduction circuit is smaller than that of the charging resistor when the one-way conduction circuit is conducted.

3. The communication assembly of claim 2, wherein the unidirectional conducting circuit comprises a discharge diode having an anode connected to the OE plate and a cathode connected to the common terminal.

4. The communication assembly of claim 3, wherein the fast discharge circuit further comprises a regulating resistor in series with the discharge diode.

5. The communication assembly of any of claims 1 to 4, further comprising a first isolation resistor and a second isolation resistor;

the first isolation resistor is arranged between the end A and the transmission bus, and the second isolation resistor is arranged between the end B and the transmission bus.

6. The communication assembly of claim 1, wherein the 485 chip is a MAX485 chip.

7. A communication system comprising a communication assembly according to any of claims 1 to 6.

Technical Field

The present invention relates to the field of communications, and in particular, to a communication module and a communication system.

Background

RS485 is a standard defined to balance the electrical characteristics of drivers and receivers in digital multipoint systems, which is defined by the telecommunications industry association and the electronics industry consortium. The digital communication network using the standard can effectively transmit signals under long-distance conditions and in environments with large electronic noise. RS-485 enables the configuration of inexpensive local networks and multi-drop communication links.

In the prior art, in order to prevent 485 circuit nodes from being damaged, various external protections are often adopted to prevent the 485 circuit nodes from being damaged, but the method is high in cost and unobvious in effect, once the 485 circuit nodes are damaged, the prior art can only carry out selective reset deadlock circuit through software, of course, the program is required to work normally, the main control chip is not damaged, and once the main control chip is damaged, the phenomenon that the 485 chip continuously sends redundant signals to cause transmission bus blockage to cause locking cannot be effectively solved.

Therefore, it is an urgent need to solve the problem in the art to find a method that does not require complex modification of the circuit, has a simple process, and can solve the problem of bus deadlock caused by damage to the main control chip.

Disclosure of Invention

The invention aims to provide a communication assembly and a communication system, and aims to solve the problems that bus deadlock caused by damage of a main control chip cannot be solved in the prior art, complex modification needs to be carried out on the system for processing the bus deadlock, and the process difficulty is high.

In order to solve the technical problem, the invention provides a communication assembly, which comprises a main control chip, a 485 chip, a protection capacitor and a transmission bus, wherein the main control chip is connected with the 485 chip through the transmission bus;

the master control chip is connected to the OE end of the 485 chip, and the 485 chip is connected to the transmission bus through the A end and the B end of the 485 chip;

the protection capacitor is arranged between the main control chip and the OE end, wherein a polar plate of the protection capacitor close to the main control chip is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate;

the OE pole plate is connected with the public end; and a charging resistor is arranged between the OE polar plate and the common terminal.

Optionally, in the communication assembly, a unidirectional conducting circuit connected in parallel with the charging resistor is included between the OE plate and the common terminal;

the one-way conduction circuit can pass current from the OE pole plate to the public end, and the resistance value of the one-way conduction circuit is smaller than that of the charging resistor when the one-way conduction circuit is conducted.

Optionally, in the communication assembly, the unidirectional conducting circuit includes a discharge diode, an anode of the discharge diode is connected to the OE plate, and a cathode of the discharge diode is connected to the common terminal.

Optionally, in the communication assembly, the fast discharge circuit further includes an adjusting resistor, and the adjusting resistor is connected in series with the discharge diode.

Optionally, in the communication assembly, the communication assembly further includes a first isolation resistor and a second isolation resistor;

the first isolation resistor is arranged between the end A and the transmission bus, and the second isolation resistor is arranged between the end B and the transmission bus.

Optionally, in the communication assembly, the 485 chip is a MAX485 chip.

A communication system comprising a communication assembly as claimed in any preceding claim.

The communication assembly provided by the invention comprises a main control chip, a 485 chip, a protection capacitor and a transmission bus; the master control chip is connected to the OE end of the 485 chip, and the 485 chip is connected to the transmission bus through the A end and the B end of the 485 chip; the protection capacitor is arranged between the main control chip and the OE end, wherein a polar plate of the protection capacitor close to the main control chip is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate; the OE pole plate is connected with the public end; and a charging resistor is arranged between the OE polar plate and the common terminal. According to the invention, the protection capacitor is additionally arranged on the connecting passage of the OE end for communicating the main control chip and the 485 chip, so that when the MCU _ RDE signal sent to the 485 chip by the main control chip is in a high level due to the damage of the main control chip or the running of a program, the protection capacitor can discharge after being fully charged, and further the signal of the OE end is forced to be changed into a low level signal, so that the 485 chip enters a data receiving state and does not send data to the transmission bus any more, and the phenomenon that the 485 chip is locked due to continuous sending of redundant information caused by the failure of the front end is avoided. The invention also provides a communication system with the beneficial effects.

Drawings

In order to more clearly illustrate the embodiments or technical solutions of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

FIG. 1 is a schematic circuit diagram of one embodiment of a prior art circuit having a selective reset deadlock substation;

FIG. 2 is a partial circuit schematic of one embodiment of a communication assembly according to the present invention;

FIG. 3 is a partial electrical schematic diagram of another embodiment of a communication assembly according to the present invention;

fig. 4 is a partial circuit diagram of another embodiment of a communication assembly according to the present invention.

Detailed Description

FIG. 1 is a diagram of a prior art deadlock substation circuit with selective reset. The method utilizes the characteristic that the RS-485 bus is deadlocked, and the transmission enabling DE of a corresponding deadlock substation is 1, and realizes selective resetting of a circuit of the deadlock substation in the substation. In normal operation, P1.1 of the main station is set to be 0, at this time, the output of the NAND gates of the substation is high level no matter the DE state of the substation, the triode T1 is cut off, RST is low level, and the substation is not reset. When RS-485 bus deadlock is detected, the main station only needs to set P1.1 to be 1, only the NAND gate of the substation with DE of 1 outputs low level, the triode T1 is conducted, RST is high level, and the corresponding substation is reset. The nand gates of the other substations output high levels and are not reset erroneously.

The existing circuit can only solve the deadlock caused by program running, and the deadlock of device damage can not be solved. According to the scheme, a line connection (P1.1) is required to be added between the main station and each substation, so that the complexity of the system is increased, and the wiring difficulty is increased.

It should be noted that, the 485 chip is a communication chip using the rs485 standard.

The master control chip controls the receiving and transmitting state of the 485 chip through the MCU _ RDE signal. When the MCU _ RDE is at a high level, the 485 chip is in a data transmitting state, and when the MCU _ RDE is at a low level, the 485 chip is in a data receiving state.

In order that those skilled in the art will better understand the disclosure, the invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The core of the present invention is to provide a communication component, a circuit schematic diagram of one embodiment of which is shown in fig. 2, and is called as a first embodiment, and includes a main control chip 100, a 485 chip 200, a protection capacitor 300 and a transmission bus;

the master control chip 100 is connected to the OE end of the 485 chip 200, and the 485 chip 200 is connected to the transmission bus through the a end and the B end of the 485 chip 200;

the protection capacitor 300 is arranged between the main control chip 100 and the OE end, wherein a polar plate of the protection capacitor close to the main control chip 100 is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate;

the OE pole plate is connected with the public end; between the OE plate and the common, a charging resistor 500 is included.

The transmission bus is not shown in the figure, but the part connected with the end B of the end A on the right side in the figure is the transmission bus.

The communication assembly further includes a first isolation resistor 610 and a second isolation resistor 620.

The first isolation resistor 610 is disposed between the terminal a and the transmission bus, and the second isolation resistor 620 is disposed between the terminal B and the transmission bus. When the 485 chip 200 has a fault, the most frequent condition is that the voltage difference between the a terminal and the B terminal is fixed, and the problem can be solved by adding the first isolation resistor 610 and the second isolation resistor 620.

Further, the 485 chip 200 is a MAX485 chip 200.

The communication assembly provided by the invention comprises a main control chip 100, a 485 chip 200, a protection capacitor 300 and a transmission bus; the master control chip 100 is connected to the OE end of the 485 chip 200, and the 485 chip 200 is connected to the transmission bus through the a end and the B end of the 485 chip 200; the protection capacitor 300 is arranged between the main control chip 100 and the OE end, wherein a polar plate of the protection capacitor close to the main control chip 100 is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate; the OE pole plate is connected with the public end; and a charging resistor is arranged between the OE polar plate and the common terminal. According to the invention, the protection capacitor is additionally arranged on the connecting passage of the OE end for communicating the main control chip 100 and the 485 chip 200, so that when the MCU _ RDE signal sent to the 485 chip 200 by the main control chip 100 is in a high level due to the damage of the main control chip 100 or the running of a program, the protection capacitor can discharge after being fully charged, and further the signal of the OE end is forced to be changed into a low level signal, so that the 485 chip 200 enters a data receiving state and does not send data to the transmission bus any more, and the phenomenon that the 485 chip 200 is locked due to continuous sending of redundant information caused by the failure of the front end is avoided.

On the basis of the first embodiment, the communication assembly is further improved to obtain a second embodiment, and a circuit schematic diagram of the second embodiment is shown in fig. 3 and includes a main control chip 100, a 485 chip 200, a protection capacitor 300 and a transmission bus;

the master control chip 100 is connected to the OE end of the 485 chip 200, and the 485 chip 200 is connected to the transmission bus through the a end and the B end of the 485 chip 200;

the protection capacitor 300 is arranged between the main control chip 100 and the OE end, wherein a polar plate of the protection capacitor close to the main control chip 100 is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate;

the OE pole plate is connected with the public end; between the OE plate and the common terminal, a charging resistor 500 is included;

a unidirectional conducting circuit 400 connected with the charging resistor 500 in parallel is arranged between the OE polar plate and the common terminal;

the unidirectional conducting circuit 400 can pass a current from the OE plate to the common terminal, and the resistance value of the unidirectional conducting circuit 400 when conducting is smaller than that of the charging resistor 500.

The difference between this embodiment and the above embodiment is that the charging resistor 500 and the unidirectional conducting circuit 400 are added to the power-on circuit of the protection capacitor in this embodiment, and the rest of the structure is the same as that in the above embodiment, and will not be described herein again.

Furthermore, the unidirectional conducting circuit 400 includes a discharge diode 410, the anode of the discharge diode 410 is connected to the OE plate, and the cathode is connected to the common terminal, so that the discharge diode 410 has a simple structure, is low in cost, and is convenient to install.

In this embodiment, the charging resistor 500 is connected in parallel with the unidirectional conducting circuit 400 between the OE plate and the common terminal, meanwhile, the resistance value of the unidirectional conducting circuit 400 is limited to be smaller than the resistance value of the charging resistor 500 when conducting, this results in two alternative paths for current flow during charging and discharging of the OE plate of the protection capacitor, during charging, the unidirectional conducting circuit 400 is not conducting, so that it can only be charged through the circuit where the charging resistor 500 is located, and when the protection capacitor is discharged, since the resistance of the unidirectional conducting circuit 400 is typically much smaller than the charging resistor 500, current is quickly released from the unidirectional conducting circuit 400, so that the voltage of the OE signal quickly returns to a low level, the 485 chip 200 quickly returns to the data receiving state from the data sending state, and data receiving of subsequent nodes is not affected. By adjusting the resistance of the charging resistor 500 and the capacitance of the protection capacitor 300, the maximum duration of the high level of the OE terminal can be adjusted.

On the basis of the second specific embodiment, the communication assembly is further improved to obtain a third specific embodiment, and a circuit schematic diagram of the third specific embodiment is shown in fig. 4 and includes a main control chip 100, a 485 chip 200, a protection capacitor 300 and a transmission bus;

the master control chip 100 is connected to the OE end of the 485 chip 200, and the 485 chip 200 is connected to the transmission bus through the a end and the B end of the 485 chip 200;

the protection capacitor 300 is arranged between the main control chip 100 and the OE end, wherein a polar plate of the protection capacitor close to the main control chip 100 is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate;

the OE pole plate is connected with the public end; between the OE plate and the common terminal, a charging resistor 500 is included;

a unidirectional conducting circuit 400 connected with the charging resistor 500 in parallel is arranged between the OE polar plate and the common terminal;

the unidirectional conducting circuit 400 can pass current from the OE plate to the common terminal, and the resistance value of the unidirectional conducting circuit 400 is smaller than that of the charging resistor 500 when conducting;

the fast discharge circuit further includes a regulating resistor 420, and the regulating resistor 420 is connected in series with the discharge diode 410.

The difference between the present embodiment and the foregoing embodiment is that the adjusting resistor 420 is added to the unidirectional conducting circuit 400 in the present embodiment, and the rest of the structure is the same as that in the foregoing embodiment, and is not described herein again.

In this embodiment, the adjusting resistor 420 is additionally disposed in the unidirectional conducting circuit 400, and is used to adjust the resistance of the unidirectional conducting circuit 400, so that the unidirectional circuit is more matched with the electrical properties of other elements, and the discharging speed of the protection capacitor 300 is adjusted.

The invention also provides a communication system comprising the communication assembly as described in any one of the above. The communication assembly provided by the invention comprises a main control chip 100, a 485 chip 200, a protection capacitor 300 and a transmission bus; the master control chip 100 is connected to the OE end of the 485 chip 200, and the 485 chip 200 is connected to the transmission bus through the a end and the B end of the 485 chip 200; the protection capacitor 300 is arranged between the main control chip 100 and the OE end, wherein a polar plate of the protection capacitor close to the main control chip 100 is a main control polar plate, and a polar plate of the protection capacitor close to the OE end is an OE polar plate; the OE pole plate is connected with the public end; and a charging resistor is arranged between the OE polar plate and the common terminal. According to the invention, the protection capacitor is additionally arranged on the connecting passage of the OE end for communicating the main control chip 100 and the 485 chip 200, so that when the MCU _ RDE signal sent to the 485 chip 200 by the main control chip 100 is in a high level due to the damage of the main control chip 100 or the running of a program, the protection capacitor can discharge after being fully charged, and further the signal of the OE end is forced to be changed into a low level signal, so that the 485 chip 200 enters a data receiving state and does not send data to the transmission bus any more, and the phenomenon that the 485 chip 200 is locked due to continuous sending of redundant information caused by the failure of the front end is avoided.

The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

It is to be noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The communication assembly and the communication system provided by the invention are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.