An adaptive level isolation serial port communication circuit and method, and a multi-connection system

Abstract

The present application discloses an adaptive level-isolated serial communication circuit and method, and a multi-connection system, belonging to the field of multi-connection technology. The circuit includes: a host-side communication module and at least one slave-side communication module, which are connected via a three-wire communication serial port; the host-side communication module includes: a host control unit and a host receiving conversion unit; the slave-side communication module includes: a transceiver isolation unit, a slave receiving conversion unit, and a slave control unit; the host control unit is used to send and receive signals at preset time intervals through the three-wire communication serial port; the host receiving conversion unit is used to convert the signal returned by the transceiver isolation unit into a host-side standard amplitude; the slave receiving conversion unit is used to convert the signal received by the transceiver isolation unit into a slave-side standard amplitude. The present application effectively solves the problem that different slaves cannot be connected to the same host due to different operating voltages or different power supply systems.

Description

Technical Field

[0001] The present application belongs to the field of multi-connection technology, and in particular, relates to an adaptive level isolation serial communication circuit and method, and a multi-connection system. Background Art

[0002] In the technical fields of air conditioning, heat pumps, industrial control, communications, energy, etc., one-to-many host and slave communication scenarios are often encountered. For example, a multi-split central air conditioner is a system that connects one or more outdoor units to multiple indoor units. It is usually used in large places such as shopping malls and factories. The indoor and outdoor units of the multi-split system need to communicate and interconnect.

[0003] However, since multi-link systems are often complex, for example, there are different circuit operating voltages between slave systems in a multi-link system, and different slave systems cannot be connected to the same host due to different circuit operating voltages, that is, they cannot communicate with the same host. Summary of the invention

[0004] In view of this, the embodiments of the present application provide an adaptive level isolation serial port communication circuit and method, and a multi-connection system to solve the problem that different slaves cannot be connected to the same host due to different operating voltages or different power supply systems.

[0005] The embodiment of the present application provides an adaptive level isolation serial port communication circuit, comprising:

[0006] A host-side communication module and at least one slave-side communication module, wherein the host-side communication module and the slave-side communication module are connected via a three-wire communication serial port, wherein the three-wire communication serial port refers to a communication serial port including a power supply terminal, a ground terminal and a transceiver terminal;

[0007] The host-side communication module comprises: a host control unit and a host receiving conversion unit;

[0008] The transmitting end of the host control unit is connected to the transmitting and receiving end of the three-wire communication serial port, and the receiving end of the host control unit is connected to the output end of the host receiving conversion unit; the input end of the host receiving conversion unit is connected to the transmitting and receiving end of the three-wire communication serial port, the power supply end of the host receiving conversion unit is connected to the power supply end of the three-wire communication serial port, and the grounding end of the host receiving conversion unit is connected to the grounding end of the three-wire communication serial port;

[0009] The slave-side communication module comprises: a transceiver isolation unit, a slave receiving conversion unit and a slave control unit;

[0010] The first power supply end of the transceiver isolation unit is connected to the power supply end of the three-wire communication serial port, the ground end of the transceiver isolation unit is connected to the ground end of the three-wire communication serial port, the transceiver end of the transceiver isolation unit is connected to the transceiver end of the three-wire communication serial port, and the output end of the transceiver isolation unit is connected to the input end of the slave receiving conversion unit; the output end of the slave receiving conversion unit is connected to the receiving end of the slave control unit, the power supply end of the slave receiving conversion unit is connected to the power supply end of the slave control unit, and the ground end of the slave receiving conversion unit is connected to the ground end of the slave control unit; the second power supply end of the transceiver isolation unit is connected to the power supply end of the slave control unit, and the receiving end of the transceiver isolation unit is connected to the transmitting end of the slave control unit;

[0011] The host control unit is used to send and receive signals at preset time intervals through the three-wire communication serial port;

[0012] The host receiving conversion unit is used to convert the signal returned by the transceiver isolation unit into a host side standard amplitude, so that the host control unit completes signal reception;

[0013] The transceiver isolation unit is used to realize isolated communication between the host side communication module and the slave side communication module;

[0014] The slave receiving conversion unit is used to convert the signal received by the transceiver isolation unit into a slave side standard amplitude, so that the slave control unit completes signal reception.

[0015] In a possible implementation, there are multiple slave-side communication modules, wherein at least two slave-side communication modules correspond to different slave-side standard amplitudes.

[0016] In a possible implementation, the host receiving conversion unit includes:

[0017] a first transistor, a first resistor, and a second resistor;

[0018] The base of the first transistor is connected to the transceiver end of the three-wire communication serial port, the base of the first transistor is also grounded through the first resistor, the collector of the first transistor is connected to the power supply end of the three-wire communication serial port through the second resistor, the collector of the first transistor is also connected to the receiving end of the host control unit, and the emitter of the first transistor is grounded.

[0019] In a possible implementation, the host receiving conversion unit further includes:

[0020] A third resistor, the collector of the first transistor is also connected to the receiving end of the host control unit through the third resistor.

[0021] In a possible implementation, the host receiving conversion unit further includes:

[0022] A first capacitor, one end of which is grounded, and the other end of which is connected between the third resistor and a receiving end of the host control unit.

[0023] In a possible implementation, the transceiver isolation unit includes:

[0024] A first optical coupler, a second optical coupler, a fourth resistor, a fifth resistor and a sixth resistor;

[0025] Pin 1 of the first optical coupler is connected to the power supply terminal of the three-wire communication serial port, pin 3 of the first optical coupler is connected to the input terminal of the slave receiving conversion unit, and pin 4 of the first optical coupler is connected to the ground terminal of the slave control unit; two ends of the fourth resistor are respectively connected to pin 1 and pin 2 of the first optical coupler; two ends of the fifth resistor are respectively connected to pin 2 of the first optical coupler and the transceiver end of the three-wire communication serial port;

[0026] Pin 3 of the second optical coupler is connected to the transceiver end of the three-wire communication serial port, pin 4 of the second optical coupler is connected to the ground end of the three-wire communication serial port, pin 1 of the second optical coupler is connected to the power supply end of the slave control unit, two ends of the sixth resistor are respectively connected to pin 1 and pin 2 of the second optical coupler, and pin 2 of the second optical coupler is connected to the transmitting end of the slave control unit;

[0027] Among them, the first optocoupler and the second optocoupler are both composed of a light-emitting diode and a phototransistor, pin 1 is the anode of the light-emitting diode, pin 2 is the cathode of the light-emitting diode, pin 3 is the collector of the phototransistor, and pin 4 is the emitter of the phototransistor.

[0028] In a possible implementation, the transceiver isolation unit further includes:

[0029] A seventh resistor, pin 2 of the second optical coupler is connected to the transmitting end of the slave control unit through the seventh resistor.

[0030] In a possible implementation, the slave receiving conversion unit includes:

[0031] a second transistor, an eighth resistor, a ninth resistor, a tenth resistor and an eleventh resistor;

[0032] A first end of the eighth resistor is connected to the base of the second transistor, a second end of the eighth resistor is connected to pin 3 of the first optical coupler, and a second end of the eighth resistor is also connected to a power supply terminal of the slave control unit through the ninth resistor;

[0033] A first end of the tenth resistor is connected to the base of the second transistor, and a second end of the tenth resistor is connected to pin No. 4 of the first optical coupler;

[0034] The collector of the second transistor is connected to the power supply terminal of the slave control unit through the eleventh resistor, the collector of the second transistor is also connected to the receiving terminal of the slave control unit, and the emitter of the second transistor is grounded.

[0035] In a possible implementation, the slave receiving conversion unit further includes:

[0036] A twelfth resistor, the collector of the second transistor is also connected to the receiving end of the slave control unit through the twelfth resistor.

[0037] In a possible implementation, the slave receiving conversion unit further includes:

[0038] A second capacitor, one end of which is grounded, and the other end of which is connected between the twelfth resistor and the receiving end of the slave control unit.

[0039] The embodiment of the present application also provides an adaptive level isolation serial communication method, which is used in the adaptive level isolation serial communication circuit described in the above embodiment, and the method includes:

[0040] In a sending time interval, the receiving end of the host control unit is set to a high impedance state, and the sending end of the host control unit sends a data frame containing a slave address code; all slave control units perform address matching according to the slave address code received in the data frame;

[0041] During the receiving time interval, the slave control unit whose address is successfully matched sets its receiving end to a high impedance state and replies with the received data frame from its transmitting end.

[0042] The embodiment of the present application also provides a multi-connection system, including: the adaptive level isolation serial port communication circuit described in the above embodiment.

[0043] The adaptive level isolation serial communication circuit provided in the embodiment of the present application includes a host side communication module and at least one slave side communication module, wherein the host side communication module and the slave side communication module are connected via a three-wire communication serial port; the host side communication module includes: a host control unit and a host receiving conversion unit; the slave side communication module includes: a transceiver isolation unit, a slave receiving conversion unit and a slave control unit; the host control unit is used to send and receive signals at preset time intervals via the three-wire communication serial port; the host receiving conversion unit is used to convert the signal returned by the transceiver isolation unit into a host side standard amplitude so that the host control unit completes signal reception; the transceiver isolation unit is used to realize isolated communication between the host side communication module and the slave side communication module; the slave receiving conversion unit is used to convert the signal received by the transceiver isolation unit into a slave side standard amplitude so that the slave control unit completes signal reception. Compared with the prior art, the adaptive level isolation serial communication circuit of the present application adopts a three-wire isolation serial port, a host polls each slave at intervals through a transceiver circuit, and exchanges data with the polled slave, thereby realizing isolated communication between a host and multiple slaves. It can be seen that the present application effectively solves the problem that different slaves cannot be connected to the same host due to different operating voltages or different power supply systems, and the adaptive level isolation serial communication circuit of the present application has the characteristics of simple structure and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0045] Attached Figure 1 A circuit diagram of an adaptive level isolation serial communication circuit provided by the present application is shown;

[0046] Attached Figure 2 A circuit diagram of a specific adaptive level isolation serial communication circuit provided by the present application is shown;

[0047] Attached Figure 3 A flowchart of a specific adaptive level isolation serial communication method provided by the present application is shown;

[0048] Attached Figure 4 A timing diagram of a host and a slave receiving and sending signals in a sending time interval and a receiving time interval provided by the present application is shown;

[0049] Attached Figure 5 A structural schematic diagram of a multi-connection system provided by the present application is shown. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0051] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0052] In addition, the descriptions of "first", "second", etc. in this application are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0053] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0054] In addition, the technical solutions between the various embodiments of the present application can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0055] Figure 1 is a circuit diagram of an adaptive level isolation serial communication circuit provided in an embodiment of the present application, such as Figure 1 As shown, the adaptive level isolation serial communication circuit 10 includes: a host side communication module 100 and at least one slave side communication module 200, one slave side communication module 200 corresponds to one slave, such as Figure 1As shown, slave 1 , slave 2 , slave 3 , and slave 4 are respectively connected to the host for communication via a slave-side communication module 200 .

[0056] Specifically, the host-side communication module 100 and the slave-side communication module 200 are connected via a three-wire communication serial port, wherein the three-wire communication serial port refers to a communication serial port including a power supply terminal, a ground terminal and a transceiver terminal. Figure 1 The VCC terminal shown in the figure is the ground terminal. Figure 1 The GND end shown in the figure, the transceiver end is Figure 1 The TXD / RXD terminals shown in the figure, where TXD represents sending data and RXD represents receiving data.

[0057] The adaptive level isolation serial communication circuit provided in this application can realize isolated communication between a host and multiple slaves of different levels or power systems through serial communication. For example, a host-side communication module of a 5V power system can communicate with multiple slave-side communication modules of 24V, 12V, and 3.3V independent power systems, thereby realizing isolated communication between a host and multiple slaves.

[0058] The host and the slave implement isolated communication of one host to multiple slaves through the following serial communication method: a host polls each slave at intervals through a three-wire communication serial port and exchanges data with the polled slave.

[0059] Figure 2 It is a circuit diagram of a specific adaptive level isolation serial communication circuit provided in an embodiment of the present application.

[0060] like Figure 2 As shown, the host-side communication module 100 includes: a host control unit 110 and a host receiving conversion unit 120 .

[0061] Specifically, the transmitting end (TXD) of the host control unit 110 is connected to the transceiver end (TXD / RXD) of the three-wire communication serial port, and the receiving end (RXD) of the host control unit 110 is connected to the output end of the host receiving conversion unit 120; the input end of the host receiving conversion unit 120 is connected to the transceiver end (TXD / RXD) of the three-wire communication serial port, the power end of the host receiving conversion unit 120 is connected to the power end (VCC) of the three-wire communication serial port, and the ground end of the host receiving conversion unit 120 is connected to the ground end (GND) of the three-wire communication serial port.

[0062] like Figure 2 As shown, the host receiving conversion unit 120 includes: a first transistor Q2, a first resistor R6 and a second resistor R2.

[0063] Specifically, the base of the first transistor Q2 (i.e., the input end of the host receiving conversion unit 120) is connected to the transceiver end of the three-wire communication serial port, the base of the first transistor Q2 is also grounded through the first resistor R6, the collector of the first transistor Q2 is connected to the power supply end of the three-wire communication serial port through the second resistor R2, the collector of the first transistor Q2 (i.e., the output end of the host receiving conversion unit 120) is also connected to the receiving end of the host control unit 110, and the emitter of the first transistor Q2 is grounded.

[0064] like Figure 2 As shown, the host receiving conversion unit 120 further includes: a third resistor R3, and the collector of the first transistor Q2 is also connected to the receiving end of the host control unit 110 through the third resistor R3.

[0065] like Figure 2 As shown, the host receiving conversion unit 120 further includes: a first capacitor C2 , one end of which is grounded, and the other end of which is connected between the third resistor R3 and the receiving end of the host control unit 110 .

[0066] The host control unit 110 is used to send and receive signals at preset time intervals through the three-wire communication serial port; the host receiving conversion unit 120 is used to convert the signal returned by the slave communication module 200 into the standard amplitude of the host side, so that the host control unit 110 completes signal reception. For example, the 3.3V signal returned by the slave side is converted into a 5V signal on the host side, and the host side completes signal reception, that is, the communication between the host and the slave is completed.

[0067] like Figure 2 As shown, the slave-side communication module 200 includes: a transceiver isolation unit 210 , a slave receiving conversion unit 220 and a slave control unit 230 .

[0068] Specifically, taking the connection between slave 1 and the host as an example, the first power supply end of the transceiver isolation unit 210 is connected to the power supply end (VCC) of the three-wire communication serial port, the ground end of the transceiver isolation unit 210 is connected to the ground end (GND) of the three-wire communication serial port, the transceiver end of the transceiver isolation unit 210 is connected to the transceiver end (TXD / RXD) of the three-wire communication serial port, the output end of the transceiver isolation unit 210 is connected to the input end of the slave receiving conversion unit 220; the output end of the slave receiving conversion unit 220 is connected to the slave The receiving end (RXD1) of the slave control unit 230 is connected, the power supply end of the slave receiving conversion unit 220 is connected to the power supply end (VCC-A) of the slave control unit 230, and the grounding end of the slave receiving conversion unit 220 is connected to the grounding end (GND-A) of the slave control unit 230; the second power supply end of the transceiver isolation unit 210 is connected to the power supply end (VCC-A) of the slave control unit 230, and the receiving end of the transceiver isolation unit 210 is connected to the transmitting end (TXD1) of the slave control unit 230.

[0069] The transceiver isolation unit 210 includes: a first optical coupler A1, a second optical coupler A2, a fourth resistor R7, a fifth resistor R10 and a sixth resistor R16.

[0070] Specifically, pin 1 of the first optical coupler A1 is connected to the power supply terminal (VCC) of the three-wire communication serial port, pin 3 of the first optical coupler A1 is connected to the input terminal of the slave receiving conversion unit 220, and pin 4 of the first optical coupler A1 is connected to the ground terminal (GND-A) of the slave control unit 230; two ends of the fourth resistor R7 are respectively connected to pin 1 and pin 2 of the first optical coupler A1; two ends of the fifth resistor R10 are respectively connected to pin 2 of the first optical coupler A1 and the transceiver terminal (TXD / RXD) of the three-wire communication serial port;

[0071] Pin 3 of the second optocoupler A2 is connected to the transceiver end (TXD / RXD) of the three-wire communication serial port, pin 4 of the second optocoupler A2 is connected to the ground end (GND) of the three-wire communication serial port, pin 1 of the second optocoupler A2 is connected to the power supply end (VCC-A) of the slave control unit 230, two ends of the sixth resistor R16 are respectively connected to pin 1 and pin 2 of the second optocoupler A2, and pin 2 of the second optocoupler A2 is connected to the transmitting end (TXD1) of the slave control unit 230.

[0072] The optocoupler consists of a light-emitting diode and a phototransistor. Pin 1 is the anode of the light-emitting diode, pin 2 is the cathode of the light-emitting diode, pin 3 is the collector of the phototransistor, and pin 4 is the emitter of the phototransistor.

[0073] like Figure 2 As shown, the transceiver isolation unit 210 further includes: a seventh resistor R22 , and the pin 2 of the second optical coupler A2 is connected to the transmitting end (TXD1 ) of the slave control unit 230 through the seventh resistor R22 .

[0074] like Figure 2 As shown, the slave receiving conversion unit 220 includes: a second transistor Q1, an eighth resistor R4, a ninth resistor R1, a tenth resistor R15 and an eleventh resistor R8;

[0075] The first end of the eighth resistor R4 is connected to the base of the second transistor Q1, the second end of the eighth resistor R4 is connected to the pin 3 of the first optical coupler A1, and the second end of the eighth resistor R4 is also connected to the power supply terminal of the slave control unit 230 through the ninth resistor R1;

[0076] A first end of the tenth resistor R15 is connected to the base of the second transistor Q1, and a second end of the tenth resistor R15 is connected to pin No. 4 of the first optical coupler A1;

[0077] The collector of the second transistor Q1 is connected to the power supply terminal of the slave control unit 230 through the eleventh resistor R8, the collector of the second transistor Q1 is also connected to the receiving terminal of the slave control unit 230, and the emitter of the second transistor Q1 is grounded.

[0078] like Figure 2 As shown, the slave receiving conversion unit 220 further includes: a twelfth resistor R5, and the collector of the second transistor Q1 is also connected to the receiving end of the slave control unit 230 through the twelfth resistor R5.

[0079] like Figure 2 As shown, the slave receiving conversion unit 220 further includes: a second capacitor C1 , one end of which is grounded, and the other end of which is connected between the twelfth resistor R5 and the receiving end of the slave control unit 230 .

[0080] The transceiver isolation unit 210 is used to realize the isolated communication between the host-side communication module 100 and the slave-side communication module 200; the slave receiving conversion unit 220 is used to convert the signal received by the transceiver isolation unit 210 into the slave-side standard amplitude, so that the slave control unit 230 completes the signal reception. After completing the signal reception, the slave control unit 230 will reply the signal, and the host receiving conversion unit 120 converts the signal returned by the slave-side communication module 200 into the host-side standard amplitude, so that the host control unit 110 completes the signal reception.

[0081] In this embodiment, the transceiver isolation unit 210 realizes isolated signal reception through the first optical coupler A1, and realizes isolated signal transmission through the second optical coupler A2. On the other hand, since the signal amplitude output by the optical coupler may not meet the signal amplitude requirements of the slave side and the host side, the signal amplitude output by the optical coupler is converted into the standard amplitude required by the slave side and the host side through the host receiving conversion unit 120 and the slave receiving conversion unit 220, thereby realizing adaptive level isolation serial port communication between the host and slaves of different levels or power systems.

[0082] In some embodiments, the number of the slave-side communication modules 200 is multiple, wherein at least two slave-side communication modules 200 correspond to different slave-side standard amplitudes. Figure 2 The standard amplitude of slave 1 is shown to be 24V, and the standard amplitude of slave 2 is shown to be 12V.

[0083] The embodiment of the present application also provides an adaptive level isolation serial communication method, which is used in the above-mentioned adaptive level isolation serial communication circuit 10, and the method comprises the following steps:

[0084] S101, within a sending time interval, the receiving end of the host control unit 110 is set to a high impedance state, and the sending end of the host control unit 110 sends a data frame containing a slave address code; all slave control units 230 perform address matching according to the slave address code received in the data frame;

[0085] S102 , within the receiving time interval, the slave control unit 230 that has successfully matched the address sets its receiving end to a high impedance state, and sends a data reply from its sending end to respond to the data frame sent by the host control unit 110 .

[0086] The above-mentioned sending time interval and receiving time interval are pre-set time periods arranged one by one. A sending time interval is followed by a receiving time interval, which are arranged in sequence to enable a host to poll each slave at intervals through a three-wire communication serial port.

[0087] If a port is set to high impedance, the port on the communication line will not affect the level change of the communication line. In other words, setting the receiving end to high impedance can avoid affecting the sending end, and setting the sending end to high impedance can avoid affecting the receiving end.

[0088] For ease of understanding, this application also provides Figure 3 A flowchart of a specific adaptive level isolation serial port communication method is shown. Figure 4 The timing diagram shown is a timing diagram of the master and slave receiving and sending signals during the sending time interval and the receiving time interval.

[0089] The adaptive level isolation serial communication circuit of the embodiment of the present application includes a host side communication module and at least one slave side communication module, and the host side communication module and the slave side communication module are connected through a three-wire communication serial port; the host side communication module includes: a host control unit and a host receiving conversion unit; the slave side communication module includes: a transceiver isolation unit, a slave receiving conversion unit and a slave control unit; the host control unit is used to send and receive signals at preset time intervals through the three-wire communication serial port; the host receiving conversion unit is used to convert the signal returned by the transceiver isolation unit into a host side standard amplitude so that the host control unit completes signal reception; the transceiver isolation unit is used to realize isolated communication between the host side communication module and the slave side communication module; the slave receiving conversion unit is used to convert the signal received by the transceiver isolation unit into a slave side standard amplitude so that the slave control unit completes signal reception. Compared with the prior art, the adaptive level isolation serial communication circuit of the present application adopts a three-wire isolation serial port, a host polls each slave at intervals through a transceiver circuit, and exchanges data with the polled slave, thereby realizing isolated communication between a host and multiple slaves. It can be seen that the present application effectively solves the problem that different slaves cannot be connected to the same host due to different operating voltages or different power supply systems, and the adaptive level isolation serial communication circuit of the present application has the characteristics of simple structure and low cost.

[0090] Figure 5 is a structural diagram of a multi-connection system provided in an embodiment of the present application, such as Figure 5 As shown, the multi-split system includes: the adaptive level isolation serial communication circuit 10 in the above embodiment. The multi-split system can be a multi-split central air conditioner, a multi-split industrial control system, or other multi-split system requiring one-to-many master-slave communication.

[0091] It should be noted that:

[0092] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0093] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0094] In addition, the terms "first", "second", etc. used in the embodiments of the present application are only used for descriptive purposes and should not be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated in the present embodiment. Therefore, the features defined by the terms "first", "second", etc. in the embodiments of the present application can explicitly or implicitly indicate that at least one of the features is included in the embodiment. In the description of the present application, the word "multiple" means at least two or two or more, such as two, three, four, etc., unless otherwise clearly and specifically defined in the embodiments.

[0095] In this application, unless otherwise clearly specified or limited in the embodiments, the terms "installed", "connected", "connected" and "fixed" etc. appearing in the embodiments should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integrated connection. It can be understood that it can also be a mechanical connection, an electrical connection, etc.; of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements, or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific implementation situation.

[0096] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0097] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. An adaptive level isolation serial communication circuit, characterized in that: include: A host-side communication module and at least one slave-side communication module, wherein the host-side communication module and the slave-side communication module are connected via a three-wire communication serial port, wherein the three-wire communication serial port refers to a communication serial port including a power supply terminal, a ground terminal and a transceiver terminal; The host-side communication module comprises: a host control unit and a host receiving conversion unit; The transmitting end of the host control unit is connected to the transmitting and receiving end of the three-wire communication serial port, and the receiving end of the host control unit is connected to the output end of the host receiving conversion unit; the input end of the host receiving conversion unit is connected to the transmitting and receiving end of the three-wire communication serial port, the power supply end of the host receiving conversion unit is connected to the power supply end of the three-wire communication serial port, and the grounding end of the host receiving conversion unit is connected to the grounding end of the three-wire communication serial port; The slave-side communication module comprises: a transceiver isolation unit, a slave receiving conversion unit and a slave control unit; The first power supply end of the transceiver isolation unit is connected to the power supply end of the three-wire communication serial port, the ground end of the transceiver isolation unit is connected to the ground end of the three-wire communication serial port, the transceiver end of the transceiver isolation unit is connected to the transceiver end of the three-wire communication serial port, and the output end of the transceiver isolation unit is connected to the input end of the slave receiving conversion unit; the output end of the slave receiving conversion unit is connected to the receiving end of the slave control unit, the power supply end of the slave receiving conversion unit is connected to the power supply end of the slave control unit, and the ground end of the slave receiving conversion unit is connected to the ground end of the slave control unit; the second power supply end of the transceiver isolation unit is connected to the power supply end of the slave control unit, and the receiving end of the transceiver isolation unit is connected to the transmitting end of the slave control unit; The host control unit is used to send and receive signals at preset time intervals through the three-wire communication serial port; The host receiving conversion unit is used to convert the signal returned by the transceiver isolation unit into a host side standard amplitude, so that the host control unit completes signal reception; The transceiver isolation unit is used to realize isolated communication between the host side communication module and the slave side communication module; The slave receiving conversion unit is used to convert the signal received by the transceiver isolation unit into a slave side standard amplitude, so that the slave control unit completes signal reception.

2. The adaptive level isolation serial communication circuit according to claim 1, characterized in that: The number of the slave-side communication modules is multiple, wherein at least two slave-side communication modules correspond to different slave-side standard amplitudes.

3. The adaptive level isolation serial communication circuit according to claim 1, characterized in that: The host receiving conversion unit comprises: a first transistor, a first resistor, and a second resistor; The base of the first transistor is connected to the transceiver end of the three-wire communication serial port, the base of the first transistor is also grounded through the first resistor, the collector of the first transistor is connected to the power supply end of the three-wire communication serial port through the second resistor, the collector of the first transistor is also connected to the receiving end of the host control unit, and the emitter of the first transistor is grounded.

4. The adaptive level isolation serial communication circuit according to claim 3, characterized in that: The host receiving conversion unit further includes: A third resistor, the collector of the first transistor is also connected to the receiving end of the host control unit through the third resistor.

5. The adaptive level isolation serial communication circuit according to claim 4, characterized in that: The host receiving conversion unit further includes: A first capacitor, one end of which is grounded, and the other end of which is connected between the third resistor and a receiving end of the host control unit.

6. The adaptive level isolation serial communication circuit according to claim 1, characterized in that: The transceiver isolation unit comprises: A first optical coupler, a second optical coupler, a fourth resistor, a fifth resistor and a sixth resistor; Pin 1 of the first optical coupler is connected to the power supply terminal of the three-wire communication serial port, pin 3 of the first optical coupler is connected to the input terminal of the slave receiving conversion unit, and pin 4 of the first optical coupler is connected to the ground terminal of the slave control unit; two ends of the fourth resistor are respectively connected to pin 1 and pin 2 of the first optical coupler; two ends of the fifth resistor are respectively connected to pin 2 of the first optical coupler and the transceiver end of the three-wire communication serial port; Pin 3 of the second optical coupler is connected to the transceiver end of the three-wire communication serial port, pin 4 of the second optical coupler is connected to the ground end of the three-wire communication serial port, pin 1 of the second optical coupler is connected to the power supply end of the slave control unit, two ends of the sixth resistor are respectively connected to pin 1 and pin 2 of the second optical coupler, and pin 2 of the second optical coupler is connected to the transmitting end of the slave control unit; Among them, the first optocoupler and the second optocoupler are both composed of a light-emitting diode and a phototransistor, pin 1 is the anode of the light-emitting diode, pin 2 is the cathode of the light-emitting diode, pin 3 is the collector of the phototransistor, and pin 4 is the emitter of the phototransistor.

7. The adaptive level isolation serial communication circuit according to claim 6, characterized in that: The transceiver isolation unit further includes: A seventh resistor, pin 2 of the second optical coupler is connected to the transmitting end of the slave control unit through the seventh resistor.

8. The adaptive level isolation serial communication circuit according to claim 6, characterized in that: The slave receiving conversion unit comprises: a second transistor, an eighth resistor, a ninth resistor, a tenth resistor and an eleventh resistor; A first end of the eighth resistor is connected to the base of the second transistor, a second end of the eighth resistor is connected to pin 3 of the first optical coupler, and a second end of the eighth resistor is also connected to a power supply terminal of the slave control unit through the ninth resistor; A first end of the tenth resistor is connected to the base of the second transistor, and a second end of the tenth resistor is connected to pin No. 4 of the first optical coupler; The collector of the second transistor is connected to the power supply terminal of the slave control unit through the eleventh resistor, the collector of the second transistor is also connected to the receiving terminal of the slave control unit, and the emitter of the second transistor is grounded.

9. The adaptive level isolation serial communication circuit according to claim 8, characterized in that: The slave receiving conversion unit further includes: A twelfth resistor, the collector of the second transistor is also connected to the receiving end of the slave control unit through the twelfth resistor.

10. The adaptive level isolation serial communication circuit according to claim 9, characterized in that: The slave receiving conversion unit further includes: A second capacitor, one end of which is grounded, and the other end of which is connected between the twelfth resistor and the receiving end of the slave control unit.

11. An adaptive level isolation serial port communication method, characterized in that: The adaptive level isolation serial communication circuit according to any one of claims 1 to 10, the method comprising: In a sending time interval, the receiving end of the host control unit is set to a high impedance state, and the sending end of the host control unit sends a data frame containing a slave address code; all slave control units perform address matching according to the slave address code received in the data frame; During the receiving time interval, the slave control unit whose address is successfully matched sets its receiving end to a high impedance state and sends a data reply from its transmitting end.

12. A multi-link system, characterized in that: The invention comprises the adaptive level isolation serial communication circuit according to any one of claims 1 to 10.

Images