A master control circuit based on communication and firmware programming

Abstract

This invention relates to the field of firmware burning technology, and particularly to a main control circuit based on communication and firmware burning. It includes: a main control chip, a data transmission interface, and a power transmission interface, one end of which is used to connect to an external device or a burning device; a power transmission switching device, whose first end is connected to the other end of the power transmission interface, its second end is connected to an external power supply, and its third end is connected to the power supply terminal of the main control chip, with the main control chip controlling the connection to the power transmission switching device; a data transmission switching device, whose first end is connected to the other end of the data transmission interface, its second end is connected to the communication terminal of the main control chip, and its third end is connected to the burning terminal of the main control chip, with the main control chip controlling the connection to the data transmission switching device; and a voltage acquisition device, whose one end is connected to the power transmission interface and its other end is connected to the input terminal of the main control chip. This invention multiplexes the data transmission interface and uses a communication line to connect to the burning terminal of the main control chip to complete firmware burning, resulting in fast and reliable firmware burning.

Description

Technical Field

[0001] This invention relates to the field of firmware burning technology, and in particular to a master control circuit based on communication and firmware burning. Background Technology

[0002] Firmware burning is a fundamental step and operation in the field of electronic engineering. It involves writing a binary executable file into the memory of a microcontroller, DSP, FPGA, or other main control chip to enable various control functions of the chip. It is widely used in research and development and after-sales firmware upgrades.

[0003] Currently, there are three commonly used methods for firmware flashing: 1. For example Figure 1 As shown, a dedicated programming pin (i.e., the MCU programming pin, mainly composed of CLK and DIO pins) is used, such as SWD programming. This pin is connected to the programming device via a terminal block. The programming device provides the main control chip (MCU) with operating power (usually 5V or 3.3V) and performs firmware programming through the firmware programming pin. However, using a dedicated programming pin for firmware programming requires an external terminal block (i.e., a dedicated external firmware programming terminal). If no external terminal block is used, the motherboard enclosure needs to be opened for connection during firmware programming, which not only increases the workload but also compromises the airtightness of the motherboard enclosure. If an external terminal block is used, a separate firmware programming port needs to be reserved, which not only occupies motherboard space but also makes the design of the circuit board enclosure more complex. In some cases, waterproofing and dustproofing of the port also need to be considered, increasing design difficulty and cost.

[0004] 2. For example Figure 2 As shown, firmware can be burned by connecting to the main control chip using wireless communication devices such as Bluetooth, enabling remote and wireless operation. However, wireless firmware burning is susceptible to signal interference, has a long burning time and low success rate, and requires the installation of a wireless data receiving device on the motherboard, significantly increasing costs.

[0005] 3. For example Figure 3 As shown, a communication line (such as CAN, RS485, etc.) is used to determine whether the firmware burning mode is enabled, thereby realizing firmware burning via the communication line. However, firmware upgrades using a communication line are difficult to develop software for, and the firmware burning time is long with a low success rate.

[0006] Therefore, a fast, stable, and low-cost firmware burning technology solution needs to be proposed. Summary of the Invention

[0007] In view of this, the present invention provides a main control circuit based on communication and firmware burning, providing an effective technical solution for fast, stable and low-cost firmware burning.

[0008] This application provides a master control circuit based on communication and firmware burning, including: The main control chip includes a communication terminal, a programming terminal, a power transmission switching control terminal, a data transmission switching control terminal, an input terminal, and a power supply terminal. The power supply terminal of the main control chip is used to connect to an external power supply. The data transmission interface and the power transmission interface are used to connect to the communication terminal of an external device or the output terminal of the burning device; the power transmission interface is used to connect to the power supply terminal of an external device or the power supply terminal of the burning device. The power transmission switching device has a first end connected to the other end of the power transmission interface, a second end connected to an external power supply, and a third end connected to the power supply terminal of the main control chip. The power transmission switching control terminal of the main control chip controls the connection of the power transmission switching device to control the switching conduction of the first end and the second end, and the first end and the third end of the power transmission switching device. The data transmission switching device has a first end connected to the other end of the data transmission interface, a second end connected to the communication end of the main control chip, and a third end connected to the programming end of the main control chip. The data transmission switching control end of the main control chip controls the connection of the data transmission switching device to control the switching connection between the first end and the second end, and between the first end and the third end of the data transmission switching device. The voltage acquisition device has one end connected to the power transmission interface and the other end connected to the input terminal of the main control chip. The main control chip controls the power transmission switching device and the data transmission switching device to switch according to the voltage magnitude acquired by the voltage acquisition device.

[0009] Compared with existing technologies, the main control circuit based on communication and firmware burning of the present invention has the following advantages: Based on the voltage of the power transmission interface, the present invention realizes the switching between external power supply and power supply of the burning device through a power transmission switching device, realizes the switching between communication and burning through a data transmission switching device, multiplexes the data transmission interface, and uses a communication line to connect to the burning end of the main control chip to complete the firmware burning. This process uses the dedicated firmware burning pin of the main control chip, which is fast, stable and reliable, and does not require the addition of a dedicated firmware burning terminal, reducing cost and design difficulty.

[0010] Furthermore, the data transmission switching device includes a switching switch, the stationary contact of the switching switch is connected to the other end of the data transmission interface, the first moving contact of the switching switch is connected to the communication end of the main control chip, the second moving contact of the switching switch is connected to the programming end of the main control chip, and the control end of the switching switch is connected to the data transmission switching control end of the main control chip.

[0011] Furthermore, the switching switch is a relay-type switching switch, with the control coil of the switching switch connected in series between the input terminal of transistor Q2 and the DC power supply, the output terminal of transistor Q2 grounded, and the control terminal of transistor Q2 connected to the data transmission switching control terminal of the main control chip.

[0012] Furthermore, a capacitor C and a diode D1 are connected in parallel across the two ends of the control coil.

[0013] Furthermore, the power transmission switching device includes a first power supply branch and a second power supply branch, one end of which is connected to the other end of the power transmission interface; the other end of the first power supply branch is used to connect to an external power source, and a control switch is provided on the first power supply branch, the control terminal of which is connected to the power transmission switching control terminal of the main control chip; a switching transistor is connected in series on the second power supply branch, the input terminal of which is connected to the other end of the power transmission interface, the output terminal of which is connected to the power supply terminal of the main control chip, the control terminal of which is connected to the first power supply branch and grounded.

[0014] Furthermore, a power conversion device is connected in series on the first power supply branch, and the control switch includes a first switch and a second switch. The first switch is located between the power conversion device and the external power supply, and the second switch is located between the power conversion device and the other end of the power transmission interface.

[0015] Furthermore, the output terminal of the switching transistor is connected to the power supply terminal of the main control chip through diode D2, and the power supply terminal of the main control chip is grounded through resistor R5.

[0016] Furthermore, the switching transistor is a PNP type transistor.

[0017] Furthermore, the voltage acquisition device includes a voltage divider branch, one end of which is connected to the power transmission interface and the other end is grounded. The voltage divider point of the voltage divider branch is connected to the input terminal of the main control chip.

[0018] Furthermore, the data transmission interface and the power transmission interface are integrated into a single external terminal. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, 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 the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the first firmware burning method in the prior art; Figure 2 This is a schematic diagram of the second firmware burning method in the prior art; Figure 3This is a schematic diagram of the third firmware burning method in the prior art; Figure 4 This is a schematic diagram of the main control circuit based on communication and firmware burning in this invention. Figure 5 This is a circuit diagram of the main control circuit based on communication and firmware burning in this invention; Figure 6 This is a flowchart of the main control circuit based on communication and firmware burning in this invention; In the diagram, 1 is the main control chip, 2 is the data transmission switching device, 3 is the data transmission interface, 4 is the power transmission interface, 5 is the external device or programming device, 6 is the voltage acquisition device, 7 is the external power supply, and 8 is the power transmission switching device. Implementation

[0021] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0022] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0023] It should also be understood that the term “and / or” as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0024] As used in this specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0025] Furthermore, in the description of this invention and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of the invention include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0027] It should be understood that the sequence number of each step in the following embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0028] To illustrate the technical solution of the present invention, specific embodiments are described below.

[0029] This invention proposes a main control circuit based on communication and firmware burning, such as... Figure 4 As shown, it includes a main control chip 1, a data transmission switching device 2, a data transmission interface 3, a power transmission interface 4, an external device or a programming device 5, a voltage acquisition device 6, an external power supply 7, and a power transmission switching device 8.

[0030] The main control chip 1 includes a communication terminal, a programming terminal, a power transmission switching control terminal, a data transmission switching control terminal, an input terminal, and a power supply terminal. The power supply terminal of the main control chip 1 is connected to an external power supply 7.

[0031] One end of the data transmission interface 3 (hereinafter referred to as the data interface) is used to connect to the communication end of an external device or to the output end of a burning device; the other end of the data transmission interface 3 is connected to the first end of the data transmission switching device 2, the second end of the data transmission switching device 2 is connected to the communication end of the main control chip 1, the third end of the data transmission switching device 2 is connected to the burning end of the main control chip 1, and the data transmission switching control end of the main control chip 1 controls the connection of the data transmission switching device 2 to control the switching connection between the first end and the second end, and between the first end and the third end of the data transmission switching device 2, thereby realizing the switching between communication function and burning function.

[0032] One end of the power transmission interface 4 is used to connect to the power supply end of an external device or the power supply end of a burning device; the other end of the power transmission interface 4 is connected to the first end of the power transmission switching device 8, the second end of the power transmission switching device 8 is connected to the external power supply 7, and the third end of the power transmission switching device 8 is connected to the power supply end of the main control chip 1. The power transmission switching control end of the main control chip 1 controls the connection to the power transmission switching device 8 to control the switching conduction of the first end and the second end, and the first end and the third end of the power transmission switching device 8, thereby realizing the switching of the external power supply 7 (hereinafter referred to as the external power supply) to supply power to the external device and the main control chip 1, and the switching of the burning device to supply power to the main control chip 1.

[0033] The voltage acquisition device 6 is used to acquire the voltage of the power transmission interface 4 (hereinafter referred to as the power transmission port). One end of the voltage acquisition device 6 is connected to the power transmission interface 4, and the other end is connected to the input terminal of the main control chip 1. The main control chip 1 controls the power transmission switching device 8 and the data transmission switching device 2 to switch according to the voltage acquired by the voltage acquisition device 6.

[0034] The specific circuit of the main control circuit based on communication and firmware burning is as follows: Figure 5 As shown: The external power supply VDC is connected to the power supply terminal VCC of the main control chip 1 through a power-on circuit, so that the external power supply VDC can provide power to the main control chip 1 for startup. VCC is usually 5V or 3.3V.

[0035] The data interfaces S1 / S2 and the power supply ports V+ / GND are integrated into a single external terminal to reduce the overall circuit size.

[0036] The data transmission switching device 2 includes a switching switch K1, which is a relay-type switching switch K1. The switching switch K1 includes a control coil, a stationary contact, and two moving contacts (a first moving contact and a second moving contact). The stationary contact of the switching switch K1 is used as the first end of the data transmission switching device 2 and connected to the other end of the data interface S1 / S2. The first moving contact of the switching switch K1 is used as the second end of the data transmission switching device 2 and connected to the communication terminal T1 / T2 of the main control chip 1 through a communication chip (the power supply of the communication chip is provided by the power supply terminal VCC of the main control chip 1). The second moving contact of the switching switch K1 is used as the third end of the data transmission switching device 2 and connected to the programming terminal DIO / CLK of the main control chip 1. The control coil of the switch K1 is connected in series between the input terminal of transistor Q2 and the DC power supply (which is also the power supply terminal VCC of the main control chip 1). A capacitor C and a diode D1 are connected in parallel across the two ends of the control coil. The output terminal of transistor Q2 is grounded. The control terminal of transistor Q2 is connected to the data transmission switching control terminal IO1 of the main control chip 1 through a resistor R1. A resistor R2 is set between the control terminal and the output terminal of transistor Q2.

[0037] The power transmission switching device 8 includes a first power supply branch and a second power supply branch. The two ends of the first power supply branch are the first end and the second end of the power transmission switching device 8, and the two ends of the second power supply branch are the first end and the third end of the power transmission switching device 8. One end of the first power supply branch and the second power supply branch are connected to the other end of the power transmission port. The other end of the first power supply branch is connected to the external power supply VDC. The first power supply branch is equipped with a control switch SW2, a power conversion device (the power supply of the power conversion device is provided by the power supply terminal VCC of the main control chip 1), and a control switch SW1. The control switch SW1 is located at the input terminal Vin of the power conversion device and at the output terminal Vout of the power conversion device. The main control chip 1 has two power switching control terminals, IO2 and IO3. The power switching control terminal IO2 of the main control chip 1 controls and connects to the control switch SW2, and the power switching control terminal IO3 of the main control chip 1 controls and connects to the control switch SW1. The first power supply branch is used to realize the power supply of the external power supply VDC to external devices. The other end of the second power supply branch is connected to the power supply terminal VCC of the main control chip 1. A switching transistor Q1 is connected in series on the second power supply branch. The switching transistor Q1 is a PNP type transistor. The input terminal of the switching transistor Q1 is connected to the other end of the power transmission port. The output terminal of the switching transistor Q1 is connected to the power supply terminal VCC of the main control chip 1 through diode D2. The power supply terminal VCC of the main control chip 1 is grounded through resistor R5. The control terminal of the switching transistor Q1 is connected to the first power supply branch through resistor R7. Specifically, it is connected between the control switch SW1 and the power conversion device. The control terminal is grounded through resistors R7 and R6. The second power supply branch is used to enable the programming device to supply power to the main control chip 1 when the programming device is connected.

[0038] The voltage acquisition device 6 includes a voltage divider branch consisting of resistors R3 and R4. One end of the voltage divider branch is connected to the power transmission port, and the other end is grounded. The voltage divider point (i.e. the connection point of resistors R3 and R4) is connected to the input terminal ADC1 of the main control chip 1, which is used to send the acquired voltage of the power transmission port to the main control chip 1.

[0039] The workflow of the main control circuit based on communication and firmware burning is as follows: Figure 6 As shown, the process is as follows: When the motherboard is working normally, i.e., when the external terminal is connected to an external device: Upon power-on, the power supply terminal VCC of the main control chip 1 is energized, and the main control chip 1 begins to operate. Since the external terminal is connected to an external device, the voltage acquired by the voltage acquisition device 6 is the supply voltage from the external power supply VDC to the external device, which is 0 or Vout. Consequently, the input terminal ADC1 of the main control chip 1 detects that the voltage value at the power input port is 0 or Vout, and sends commands to the power switching control terminals IO2 and IO3 of the main control chip 1, controlling the control switches SW1 and SW2 to remain on, ensuring Vout provides normal external power. With the switching transistor Q1 in the off state, Vout and VCC are separated, and the data transmission switching control terminal IO1 of the main control chip 1 outputs a high level. The switching switch K1 activates, connecting the stationary contact of the switching switch K1 to the first moving contact, switching the data interface S1 / S2 to the communication chip. Thus, the main control chip 1 communicates normally with the external device, and the motherboard operates normally.

[0040] Firmware burning, i.e., when the external terminal is connected to the burning device, the power supply terminal VCC / GND and the output terminal DIO / CLK of the burning device are connected to the power input port V+ / GND and the data interface S1 / S2 of the external terminal, respectively. The burning device's VCC supplies power to the motherboard through the second power supply branch. At this time, the switching transistor Q1 is turned on, the power supply terminal VCC of the main control chip 1 is energized, and the main control chip 1 starts working. At this time, the voltage of the power input port is the power supply voltage of the burning device. The power supply voltage of the burning device is the same as the operating voltage of the main control chip 1, so the voltage value is VCC. The input terminal ADC of the main control chip 1... Upon detecting a voltage value of VCC, commands are sent to the power switching control terminals IO2 and IO3 of the main control chip 1, causing control switches SW1 and SW2 to disconnect. Switch Q1 remains on, meaning the power supply terminal VCC of the main control chip 1 remains energized. The data transmission switching control terminal IO1 of the main control chip 1 outputs a low level, and switch K1 remains inactive. The stationary contact of switch K1 connects to the second moving contact. At this time, the output terminal DIO / CLK of the programming device is connected to the programming terminal DIO / CLK of the main control chip 1 through data interfaces S1 / S2, allowing firmware programming to proceed. Furthermore, during firmware programming, the data transmission switching control terminal IO1, and the power switching control terminals IO2 and IO3 have no output, keeping switches K1, SW1, and SW2 in their original inactive / disconnected state. This matches the required operating state for firmware programming, thus successfully achieving firmware programming.

[0041] In the above embodiments, the data interface S1 / S2 is a reusable interface that realizes both communication and programming functions. The communication line includes CAN, RS485, etc. This invention does not limit this, and any externally connectable communication terminal line can be reused.

[0042] In the above embodiments, the dedicated programming port of the main control chip 1 includes the CLK and DIO pins of ARM core chips. In other implementations, the firmware programming pins RES and FINED of Renesas chips can also be used, and the present invention does not limit this.

[0043] In the above embodiments, the switching switch K1, switching transistor Q1, control switch SW1, control switch SW2, and transistor Q2 can be various mechanical or electronic switches such as relays, transistors, and MOSFETs, and the present invention does not limit them.

[0044] In the above embodiments, in order to reduce the circuit size, the data transmission interface 3 and the power transmission interface 4 are integrated into one external terminal. Of course, as other embodiments, the data transmission interface 3 and the power transmission interface 4 can also be set separately, and the present invention does not limit this.

[0045] In the above embodiments, in order to save costs, the voltage acquisition device 6 uses a voltage divider branch for voltage acquisition. As another implementation, a dedicated voltage acquisition chip can also be used for voltage acquisition, and the present invention does not limit this.

[0046] Regarding the power transmission switching device 8 and the data transmission switching device 2, there are various specific circuit designs that can achieve the same function. This invention does not limit the specific circuits of the power transmission switching device 8 and the data transmission switching device 2, as long as they can achieve the corresponding functions.

[0047] The circuit of this invention realizes the switching of data transmission and power transmission by detecting the voltage value of the power transmission interface 4, and realizes the connection of the multiplexed communication line to the burning terminal of the main control chip 1 to complete the firmware burning. This process uses the dedicated firmware burning pin of the main control chip 1, which is fast, stable and reliable, and does not require the addition of a dedicated firmware burning terminal, reducing cost and design difficulty. At any given time, the motherboard can only be in normal operation or firmware burning state.

[0048] The circuit of this invention can be applied to any motherboard that requires firmware burning, especially in situations where the motherboard needs to be sealed and difficult to disassemble. Firmware burning and upgrading can be completed simply by using the communication and external power supply ports.

[0049] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A master control circuit based on communication and firmware burning, characterized in that, include: The main control chip includes a communication terminal, a programming terminal, a power transmission switching control terminal, a data transmission switching control terminal, an input terminal, and a power supply terminal. The power supply terminal of the main control chip is used to connect to an external power supply. The data transmission interface and the power transmission interface are used to connect to the communication terminal of an external device or the output terminal of the burning device; the power transmission interface is used to connect to the power supply terminal of an external device or the power supply terminal of the burning device. The power transmission switching device has a first end connected to the other end of the power transmission interface, a second end connected to an external power supply, and a third end connected to the power supply terminal of the main control chip. The power transmission switching control terminal of the main control chip controls the connection of the power transmission switching device to control the switching conduction of the first end and the second end, and the first end and the third end of the power transmission switching device. The data transmission switching device has a first end connected to the other end of the data transmission interface, a second end connected to the communication end of the main control chip, and a third end connected to the programming end of the main control chip. The data transmission switching control end of the main control chip controls the connection of the data transmission switching device to control the switching connection between the first end and the second end, and between the first end and the third end of the data transmission switching device. The voltage acquisition device has one end connected to the power transmission interface and the other end connected to the input terminal of the main control chip. The main control chip controls the power transmission switching device and the data transmission switching device to switch according to the voltage magnitude acquired by the voltage acquisition device.

2. The main control circuit based on communication and firmware burning according to claim 1, characterized in that, The data transmission switching device includes a switching switch. The stationary contact of the switching switch is connected to the other end of the data transmission interface. The first moving contact of the switching switch is connected to the communication terminal of the main control chip. The second moving contact of the switching switch is connected to the programming terminal of the main control chip. The control terminal of the switching switch is connected to the data transmission switching control terminal of the main control chip.

3. The main control circuit based on communication and firmware burning according to claim 2, characterized in that, The switching switch is a relay-type switching switch. The control coil of the switching switch is connected in series between the input terminal of transistor Q2 and the DC power supply. The output terminal of transistor Q2 is grounded. The control terminal of transistor Q2 is connected to the data transmission switching control terminal of the main control chip.

4. The main control circuit based on communication and firmware burning according to claim 3, characterized in that, A capacitor C and a diode D1 are connected in parallel across the two ends of the control coil.

5. The main control circuit based on communication and firmware burning according to claim 1, characterized in that, The power transmission switching device includes a first power supply branch and a second power supply branch. One end of the first power supply branch and the second power supply branch are connected to the other end of the power transmission interface. The other end of the first power supply branch is used to connect to an external power source. A control switch is provided on the first power supply branch, and the control terminal of the control switch is connected to the power transmission switching control terminal of the main control chip. A switching transistor is connected in series on the second power supply branch. The input terminal of the switching transistor is connected to the other end of the power transmission interface, the output terminal is connected to the power supply terminal of the main control chip, the control terminal is connected to the first power supply branch, and the control terminal is grounded.

6. The main control circuit based on communication and firmware burning according to claim 5, characterized in that, A power conversion device is connected in series on the first power supply branch, and the control switch includes a first switch and a second switch. The first switch is located between the power conversion device and the external power supply, and the second switch is located between the power conversion device and the other end of the power transmission interface.

7. The main control circuit based on communication and firmware burning according to claim 5, characterized in that, The output terminal of the switching transistor is connected to the power supply terminal of the main control chip through diode D2, and the power supply terminal of the main control chip is grounded through resistor R5.

8. The main control circuit based on communication and firmware burning according to claim 5, characterized in that, The switching transistor is a PNP type transistor.

9. The main control circuit based on communication and firmware burning according to claim 1, characterized in that, The voltage acquisition device includes a voltage divider branch, one end of which is connected to the power transmission interface and the other end is grounded. The voltage divider point of the voltage divider branch is connected to the input terminal of the main control chip.

10. The main control circuit based on communication and firmware burning according to claim 1, characterized in that, The data transmission interface and the power transmission interface are integrated into a single external terminal.

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