Serial port double-transmitting single-receiving circuit

Abstract

The utility model relates to the technical field of transceiving circuits, in particular to a serial port double-transmitting single-receiving circuit, which comprises a first transmitting module, a second transmitting module and a receiving module. A power supply end is connected with the first transmitting module through the first one-way conduction module, is connected with the second transmitting module through the second one-way conduction module in parallel, and is connected with the receiving module in parallel; when the first transmitting module or the second transmitting module works, the first one-way conduction module or the second one-way conduction module is cut off, and the receiving module works. The device solves the problems that when serial communication fails, the receiving device 3 needs RX1 and RX2 to monitor TX data of the device 1 and the device 2 respectively, so that the number of occupied serial ports is large, and the communication efficiency is low.

Description

Technical Field

[0001] This utility model relates to the field of transceiver circuit technology, and in particular to a serial port dual-transmitter single-receiver circuit. Background Technology

[0002] A serial port, also known as a serial communication interface (usually referring to a COM interface), is an expansion interface that uses serial communication. A serial interface transmits data bit by bit sequentially. Its advantages include simple communication lines; only a pair of transmission lines are needed for bidirectional communication, and telephone lines can be used, significantly reducing costs. It is particularly suitable for long-distance communication, but its transmission speed is relatively slow.

[0003] In electronic products, there are many ways to use serial ports, and serial communication failures are a frequent occurrence. When communication fails, we use another receiving device 3 to detect the TX data of both device 1 and device 2 to check if there is an acknowledgment between the two devices and whether the returned data is correct. However, the conventional method requires two sets of serial ports for device 3, using RX1 and RX2 of device 3 to detect the TX of device 1 and device 2 respectively. This results in low communication efficiency and requires a large number of serial ports. Utility Model Content

[0004] The utility model of this invention provides a serial port dual-transmitter single-receiver circuit, which mainly solves the problem that when serial communication fails, the receiving device 3 needs RX1 and RX2 to monitor the TX data of device 1 and device 2 respectively, resulting in a large number of serial ports being occupied and low communication efficiency.

[0005] This utility model proposes a serial port dual-transmit single-receive circuit, including a first transmitting module, a second transmitting module and a receiving module;

[0006] The power supply is connected to the first transmitting module through a first unidirectional conducting module, and is connected in parallel to the second transmitting module through a second unidirectional conducting module, and is also connected in parallel to the receiving module;

[0007] When the first transmitting module or the second transmitting module is working, the first unidirectional conduction module or the second unidirectional conduction module is turned off, and the receiving module is working.

[0008] Preferably, the first transmitting module includes a diode D1; the second transmitting module includes a diode D2;

[0009] The transmitting end of the first transmitting module is connected to the negative terminal of the diode D1, and the power supply end is connected to the positive terminal of the diode D1;

[0010] The transmitting end of the second transmitting module is connected to the negative terminal of the diode D2, and the power supply end is connected to the positive terminal of the diode D2.

[0011] Preferably, it further includes a resistor R1; the power supply terminal is connected to the resistor R1, and the other end of the resistor R1 is connected in parallel to the diode D1, the diode D2 and the receiving module.

[0012] Preferably, when the first transmitting module transmits high-level data, diode D1 is turned off, and the receiving module receives the high level through pull-up resistor R1; when the first transmitting module transmits low-level data, diode D1 is turned on, and the receiving module receives the low level.

[0013] When the second transmitting module sends high-level data, diode D2 is turned off, and the receiving module receives the high level through pull-up resistor R1; when the second transmitting module sends low-level data, diode D2 is turned on, and the receiving module receives the low level.

[0014] Preferably, the first transmitting module, the second transmitting module, and the receiving module are located in the first peripheral, the second peripheral, and the third peripheral, respectively;

[0015] The first peripheral and the second peripheral are in a half-duplex working state.

[0016] Preferably, it further includes a first filter module and a second filter module; the output terminal of the first transmitting module is connected to the first filter module; the output terminal of the second transmitting module is connected to the second filter module.

[0017] As can be seen from the above, the following beneficial effects can be obtained by applying the technical solution provided by this utility model:

[0018] First, the serial port dual-transmitter single-receiver circuit proposed in this utility model can verify the two TX transmit lines through one RX receive line when the serial communication fails, thereby improving communication efficiency and reducing the number of serial ports occupied, making the dual-transmitter single-receiver circuit more adaptable.

[0019] Secondly, the serial port dual-transmitter single-receiver circuit proposed in this utility model achieves the single-receiver effect of two transmitting modules through diodes and pull-up resistors. Its components are simple, the cost is low, and it is easy to implement. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a circuit diagram of the serial port dual-transmitter single-receiver circuit in an embodiment of this utility model. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0023] When serial communication fails, receiving device 3 needs RX1 and RX2 to monitor the TX data of device 1 and device 2 respectively, resulting in a large number of serial ports being occupied and low communication efficiency.

[0024] like Figure 1 As shown, to solve the above problems, this embodiment proposes a serial port dual-transmitter single-receiver circuit, including a first transmitting module, a second transmitting module, and a receiving module. The power supply is connected to the first transmitting module via a first unidirectional conduction module, and in parallel to the second transmitting module via a second unidirectional conduction module. A receiving module is also connected in parallel. When either the first or second transmitting module is operating, either the first or second unidirectional conduction module is turned off, and the receiving module operates.

[0025] Preferably, in this embodiment, the first transmitting module TX1, the second transmitting module TX2 and the receiving module RX are located on device 1, device 2 and device 3 respectively, and device 1 and device 2 are in a half-duplex working state.

[0026] Preferably, in this embodiment, the first unidirectional conduction module includes diode D1, and the second unidirectional conduction module includes diode D2. The transmitting end of the first transmitting module is connected to the negative terminal of diode D1, and the power supply end is connected to the positive terminal of diode D1; the transmitting end of the second transmitting module is connected to the negative terminal of diode D2, and the power supply end is connected to the positive terminal of diode D2. Preferably, but not limited to, in this embodiment, diodes D1 and D2 constitute the key units of the unidirectional conduction module, used to limit the unidirectional conduction of electrical signals, and other components may be provided to further limit the function of the current circuit.

[0027] In this embodiment, since device 1 and device 2 are in half-duplex mode, when the first transmitting module TX1 is transmitting data, the second transmitting module TX2 will not work, and the second transmitting module TX2 will always be in a high-level state; similarly, when the second transmitting module TX2 is transmitting data, the first transmitting module TX1 will not work, and the first transmitting module TX1 will also always be in a high-level state.

[0028] More specifically, it also includes resistor R1; the power supply terminal is connected to resistor R1, and the other end of resistor R1 is connected to diode D1, diode D2 and receiver module RX.

[0029] Preferably, in this embodiment, resistor R1 is a pull-up resistor.

[0030] In this embodiment, when the first transmitting module TX1 sends high-level data, diode D1 is cut off. Since the positive terminal of diode D1 is pulled up to the input power supply VCC through the pull-up resistor R1, the receiving module RX maintains the same high-level data as the first transmitting module TX1. When the first transmitting module TX1 sends low-level data, diode D1 is turned on, and the receiving module RX also sends low-level data. When the second transmitting module TX2 sends high-level data, diode D2 is cut off. Since the positive terminal of diode D2 is pulled up to the input power supply VCC through the pull-up resistor R1, the receiving module RX maintains the same high-level data as the second transmitting module TX2. When the second transmitting module TX2 sends low-level data, diode D2 is turned on, and the level on the receiving module RX is also low.

[0031] In this embodiment, the transmitting terminals of the first transmitting module TX1 and the second transmitting module TX2 are respectively connected to filter modules. Preferably, but not limited to, the filter modules include at least one of LC circuits and RC circuits.

[0032] In summary, the serial port dual-transmitter single-receiver circuit proposed in this embodiment uses the unidirectional conduction characteristic of diodes to ensure that the TX1 of device 1 or the TX2 of device 2 in the circuit is consistent with the RX of device 3. This enables a receiving module of device 3 to judge and verify whether there is a response between device 1 and device 2 and whether the returned data is correct. At the same time, it reduces the number of serial ports required by device 3.

[0033] The embodiments described above do not constitute a limitation on the scope of protection of this technical solution. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the above embodiments should be included within the scope of protection of this technical solution.

Claims

1. A serial port dual-transmitter single-receiver circuit, characterized in that: It includes a first transmitting module, a second transmitting module, and a receiving module; The power supply is connected to the first transmitting module through a first unidirectional conducting module, and is connected in parallel to the second transmitting module through a second unidirectional conducting module, and is also connected in parallel to the receiving module; When the first transmitting module or the second transmitting module is working, the first unidirectional conduction module or the second unidirectional conduction module is turned off, and the receiving module is working.

2. The serial port dual-transmitter single-receiver circuit according to claim 1, characterized in that: The first unidirectional conduction module includes diode D1; the second unidirectional conduction module includes diode D2; The transmitting end of the first transmitting module is connected to the negative terminal of the diode D1, and the power supply end is connected to the positive terminal of the diode D1; The transmitting end of the second transmitting module is connected to the negative terminal of the diode D2, and the power supply end is connected to the positive terminal of the diode D2.

3. A serial port dual-transmitter single-receiver circuit according to claim 2, characterized in that: It also includes a resistor R1; the power supply terminal is connected to the resistor R1, and the other end of the resistor R1 is connected in parallel to the diode D1, the diode D2 and the receiving module.

4. A serial port dual-transmitter single-receiver circuit according to claim 3, characterized in that: When the first transmitting module sends high-level data, diode D1 is turned off, and the receiving module receives the high level through pull-up resistor R1; when the first transmitting module sends low-level data, diode D1 is turned on, and the receiving module receives the low level. When the second transmitting module sends high-level data, diode D2 is turned off, and the receiving module receives the high level through pull-up resistor R1; when the second transmitting module sends low-level data, diode D2 is turned on, and the receiving module receives the low level.

5. A serial port dual-transmitter single-receiver circuit according to claim 4, characterized in that: The first transmitting module, the second transmitting module, and the receiving module are located in the first peripheral, the second peripheral, and the third peripheral, respectively; The first peripheral and the second peripheral are in a half-duplex working state.

6. A serial port dual-transmitter single-receiver circuit according to any one of claims 1 to 5, characterized in that: It also includes a first filter module and a second filter module; the output terminal of the first transmitting module is connected to the first filter module; the output terminal of the second transmitting module is connected to the second filter module.

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