Time division multiplexing serial port expansion circuit

Abstract

A time division multiplexing serial port expansion circuit comprises a main control chip U6 and a digital control analog switch U5, a first pin of the main control chip U6 is connected with a thirteenth pin of the digital control analog switch U5, a second pin of the main control chip U6 is connected with a third pin of the digital control analog switch U5, a third pin of the main control chip U6 is connected with a tenth pin of the digital control analog switch U5, and a fourth pin of the main control chip U6 is connected with a fifth pin of the digital control analog switch U5. And a fourth pin of the main control chip U6 is connected with a ninth pin of the digital control analog switch U5. CD4052 is adopted for expanding multiple serial ports, time division multiplexing is achieved, and related communication ICs do not interfere with one another, so that the possibility of damage is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of audio, in particular to a circuit for time-division multiplexing serial port expansion. Background Technique

[0002] In the design of audio, it is often necessary to use the single-chip microcomputer serial port for software upgrade, authentication, tuning, or data transmission with other ICs. However, most single-chip microcomputers only have one serial port, and it is impossible to support multiple devices and various requirements at the same time.

[0003] Most manufacturers will add a multi-position small toggle switch on the PCB and manually switch it to meet various requirements such as debugging. However, there are defects: (1) For the design of the multi-position small toggle switch, if the switch is inside the machine, it is necessary to disassemble the machine when there is a need for upgrade, etc., and there is a risk of secondary damage to the machine; (2) It is easy to make mistakes in operation, and there is a possibility of damaging the relevant communication IC due to misconnection. Summary of the Invention

[0004] The technical problem to be solved by the utility model is to provide a circuit for time-division multiplexing serial port expansion, which realizes time-division multiplexing, and the associated communication ICs do not interfere with each other, reducing the possibility of damage.

[0005] To solve the above technical problem, the technical solution of the utility model is: A circuit for time-division multiplexing serial port expansion, including a main control chip U6 and a digital control analog switch U5. The first pin of the main control chip U6 is connected to the 13th pin of the digital control analog switch U5, the second pin of the main control chip U6 is connected to the 3rd pin of the digital control analog switch U5, the third pin of the main control chip U6 is connected to the 10th pin of the digital control analog switch U5, and the fourth pin of the main control chip U6 is connected to the 9th pin of the digital control analog switch U5. The principle of the utility model: This circuit expands multiple serial ports based on the digital control analog switch U5 and realizes time-division multiplexing. The main control chip U6 controls the 9th pin (i.e., control pin B) and the 10th pin (i.e., control pin A) of the digital control analog switch U5. When B = 0 and A = 0, the 13th pin of the digital control analog switch U5 is conducted with the 12th pin, and the 3rd pin is conducted with the 1st pin; when B = 0 and A = 1, the 13th pin of the digital control analog switch U5 is conducted with the 14th pin, and the 3rd pin is conducted with the 5th pin; when B = 1 and A = 0, the 13th pin of the digital control analog switch U5 is conducted with the 15th pin, and the 3rd pin is conducted with the 2nd pin; when B = 1 and A = 1, the 13th pin of the digital control analog switch U5 is conducted with the 11th pin, and the 3rd pin is conducted with the 4th pin. In summary, the single-chip microcomputer realizes time-division multiplexing multiple serial port expansion.

[0006] As an improvement, the 12th pin of the digital control analog switch U5 is connected to the 1st pin of the chip U1, and the 1st pin of the digital control analog switch U5 is connected to the 2nd pin of the chip U1; the 14th pin of the digital control analog switch U5 is connected to the 1st pin of the chip U2, and the 5th pin of the digital control analog switch U5 is connected to the 2nd pin of the chip U2; the 15th pin of the digital control analog switch U5 is connected to the 1st pin of the chip U3, and the 2nd pin of the digital control analog switch U5 is connected to the 2nd pin of the chip U3; the 11th pin of the digital control analog switch U5 is connected to the 1st pin of the chip U4, and the 4th pin of the digital control analog switch U5 is connected to the 2nd pin of the chip U4.

[0007] As an improvement, the model of the main control chip U6 is STM32F030C8T6, and the model of the digital control analog switch U5 is CD4052.

[0008] The beneficial effects brought by the present utility model compared with the prior art are as follows:

[0009] Using CD4052 to expand multiple serial ports, time-division multiplexing, the associated communication ICs do not interfere with each other, reducing the possibility of damage; controlled by a single-chip microcomputer, convenient and intelligent; the serial port can be placed outside the machine, and the requirements can be realized through buttons. Description of the Drawings

[0010] Figure 1 It is the circuit diagram of the present utility model. Detailed Embodiment

[0011] The present utility model will be further described below in conjunction with the accompanying drawings of the specification.

[0012] As Figure 1As shown in the figure, a circuit for time-division multiplexing serial port expansion includes a main control chip U6 and a digital control analog switch U5. The main control chip U6 is an MCU with the model STM32F030C8T6, and other models of MCU main control chips can also be used. The model of the digital control analog switch U5 is CD4052. The first pin of the main control chip U6 is connected to the 13th pin of the digital control analog switch U5, the second pin of the main control chip U6 is connected to the 3rd pin of the digital control analog switch U5, the third pin of the main control chip U6 is connected to the 10th pin of the digital control analog switch U5, and the fourth pin of the main control chip U6 is connected to the 9th pin of the digital control analog switch U5. The 12th pin of the digital control analog switch U5 is connected to the first pin of the chip U1, and the first pin of the digital control analog switch U5 is connected to the second pin of the chip U1. The 14th pin of the digital control analog switch U5 is connected to the first pin of the chip U2, and the 5th pin of the digital control analog switch U5 is connected to the second pin of the chip U2. The 15th pin of the digital control analog switch U5 is connected to the first pin of the chip U3, and the second pin of the digital control analog switch U5 is connected to the second pin of the chip U3. The 11th pin of the digital control analog switch U5 is connected to the first pin of the chip U4, and the fourth pin of the digital control analog switch U5 is connected to the second pin of the chip U4.

[0013] Principle of the present utility model: This circuit expands multiple serial ports based on the digital control analog switch U5 and uses time-division multiplexing. The main control chip U6 controls the 9th pin (i.e., control pin B) and the 10th pin (i.e., control pin A) of the digital control analog switch U5. When B = 0 and A = 0, the 13th pin and the 12th pin of the digital control analog switch U5 are conducted (i.e., RX is connected to RX1), and the 3rd pin and the 1st pin are conducted (i.e., TX is connected to TX1). When B = 0 and A = 1, the 13th pin and the 14th pin of the digital control analog switch U5 are conducted (i.e., RX is connected to RX2), and the 3rd pin and the 5th pin are conducted (i.e., TX is connected to TX2). When B = 1 and A = 0, the 13th pin and the 15th pin of the digital control analog switch U5 are conducted (i.e., RX is connected to RX3), and the 3rd pin and the 2nd pin are conducted (i.e., TX is connected to TX3). When B = 1 and A = 1, the 13th pin and the 11th pin of the digital control analog switch U5 are conducted (i.e., RX is connected to RX4), and the 3rd pin and the 4th pin are conducted (i.e., TX is connected to TX4). In summary, the time-division multiplexing expansion of multiple serial ports of the single-chip microcomputer is realized.

Claims

1. A circuit for time-division multiplexing serial port expansion, characterized in that: It includes a main control chip U6 and a digital control analog switch U5. The first pin of the main control chip U6 is connected to the 13th pin of the digital control analog switch U5, the second pin of the main control chip U6 is connected to the third pin of the digital control analog switch U5, the third pin of the main control chip U6 is connected to the tenth pin of the digital control analog switch U5, and the fourth pin of the main control chip U6 is connected to the ninth pin of the digital control analog switch U5.

2. The circuit for time-division multiplexing serial port expansion according to claim 1, characterized in that: The 12th pin of the digital control analog switch U5 is connected to the 1st pin of the chip U1, and the 1st pin of the digital control analog switch U5 is connected to the 2nd pin of the chip U1; The 14th pin of the digital control analog switch U5 is connected to the 1st pin of the chip U2, and the 5th pin of the digital control analog switch U5 is connected to the 2nd pin of the chip U2; The 15th pin of the digital control analog switch U5 is connected to the 1st pin of the chip U3, and the 2nd pin of the digital control analog switch U5 is connected to the 2nd pin of the chip U3; The 11th pin of the digital control analog switch U5 is connected to the 1st pin of the chip U4, and the 4th pin of the digital control analog switch U5 is connected to the 2nd pin of the chip U4.

3. The circuit for time-division multiplexing serial port expansion according to claim 1, characterized in that: The model of the main control chip U6 is STM32F030C8T6, and the model of the digital control analog switch U5 is CD4052.

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