Burning interface circuit and electronic equipment

Abstract

The invention provides a burning interface circuit and electronic equipment. The burning interface circuit comprises a watchdog chip, an MCU (Microprogrammed Control Unit), an MOS (Metal Oxide Semiconductor) tube and a burning interface, a reset pin of the watchdog chip is connected with one pin of the MCU through the first circuit. The watchdog chip is used for receiving a WDI pin of a dog feeding signal, is connected with the other pin of the MCU through a first branch of the second circuit, and is connected with one pin of the MOS tube through a second branch of the second circuit. The other pin of the MOS tube is grounded, and the control pin of the MOS tube is connected with the watchdog enabling pin of the burning interface through a third circuit. The watchdog chip is used for not outputting a reset signal when a watchdog enable pin and a grounding pin are in short circuit; and when the watchdog enabling pin and the grounding pin are disconnected, outputting a reset signal according to the dog feeding signal. In this way, different use requirements for watchdog functions in different scenes can be met.

Description

Technical Field

[0001] The present application relates to the technical field of watchdog, and more specifically, to a burning interface circuit and electronic equipment. Background Art

[0002] During the operation of electronic equipment, the system may be stuck due to external interference and cannot automatically recover to normal working state. By setting a watchdog circuit, the reliable operation of the system can be guaranteed.

[0003] The watchdog circuit is a timer circuit. When the system is operating normally, it will output a feeding signal to the watchdog circuit at regular intervals to reset the timer (commonly known as "feeding the dog"). When the system cannot output the feeding signal, the timer timeout will trigger the watchdog circuit to output a reset signal to restart the system. In this way, when the system is stuck due to factors such as freezing and cannot function, it can automatically resume normal working state.

[0004] However, during debugging and burning, the system's watchdog feeding operation may be interrupted, causing the watchdog timer to time out and trigger a system reset, so that the process is interrupted and cannot proceed normally, which is not conducive to the debugging and burning of electronic equipment, nor is it conducive to the intelligence of the equipment. Summary of the invention

[0005] The present application provides a burning interface circuit and an electronic device, which can meet different usage requirements for the watchdog function in different scenarios such as normal use and burning without changing the hardware structure of the circuit for transmitting the dog feeding signal, thereby improving the debugging efficiency and ensuring the reliability of the circuit.

[0006] In a first aspect, a programming interface circuit is provided. The programming interface circuit includes: a watchdog chip, a microcontroller unit (MCU), a programming interface and a MOS tube. The MOS tube is the abbreviation of metal oxide semiconductor field effect transistor (MOSFET).

[0007] The watchdog chip includes: a watchdog input WDI pin and a reset RESET pin, the WDI pin is used to receive a watchdog feeding signal, the RESET pin is used to output a reset signal, the watchdog feeding signal is used to indicate that the MCU is working normally, and the reset signal is used to indicate that the MCU is reset. The MCU includes: a first pin and a second pin, the first pin is used to output a watchdog feeding signal, and the second pin is used to receive a reset signal. The burning interface includes: a watchdog enable pin and a third pin for grounding. The MOS tube includes: a fourth pin, a fifth pin for connecting to the watchdog enable pin, and a sixth pin for grounding.

[0008] For example, for the burning interface circuit 10, pin 1 and pin 2 of the MCU can correspond to the first pin and the second pin respectively; pin 1 of the burning interface J1 can correspond to the watchdog enable pin; pin 1 of the burning interface J1 can correspond to the third pin; pin 1 of the MOS tube Q1 can correspond to the fourth pin; pin 2 of the MOS tube Q1 can correspond to the fifth pin; pin 3 of the MOS tube Q1 can correspond to the sixth pin.

[0009] The burning interface circuit also includes: a first circuit, a second circuit and a third circuit. The first circuit is used to connect the RESET pin of the watchdog chip and the second pin of the MCU. The second circuit includes a first branch and a second branch, the first branch is used to connect the WDI pin of the watchdog chip and the first pin of the MCU; the second branch is used to connect the WDI pin of the watchdog chip and the fourth pin of the MOS tube, the first branch and the second branch are provided with a connection point at one end close to the WDI pin, the first branch is provided with a first resistor, the second branch is provided with a second resistor, and the first resistor is smaller than the second resistor. The third circuit is used to connect the watchdog enable pin of the burning interface and the fifth pin of the MOS tube. The burning interface circuit is used to: according to the connection state between the watchdog enable pin and the third pin, enable the watchdog chip to output a reset signal.

[0010] In the present application, it is not necessary to change the hardware structure of the circuit used to transmit the dog feeding signal, so as to meet the different usage requirements of the watchdog function in different scenarios such as normal use and burning, thereby improving the debugging efficiency and ensuring the reliability of the circuit.

[0011] In some possible implementations, the watchdog chip can be used to: not output a reset signal when the watchdog enable pin and the third pin are short-circuited; and output a reset signal according to a watchdog feeding signal when the watchdog enable pin and the third pin are disconnected.

[0012] In some possible implementations, when the watchdog enable pin and the third pin are short-circuited, the fourth pin and the sixth pin of the MOS tube may be disconnected; when the watchdog enable pin and the third pin are disconnected, the fourth pin and the sixth pin of the MOS tube may be turned on.

[0013] In some possible implementations, the programming interface circuit may further include a transient voltage suppressor (TVS), one end of which may be grounded, and the other end of which may be connected to the third circuit.

[0014] In the present application, by providing a TVS tube, the instantaneous overvoltage of the third circuit can be effectively suppressed, which is beneficial to ensure that the MOS tube works in an expected manner and can improve the reliability of the burning interface circuit.

[0015] In some possible implementations, the programming interface circuit may further include a first pull-up resistor; one end of the first pull-up resistor may be connected to the third circuit.

[0016] In the present application, by setting the first pull-up resistor, it is helpful to ensure the stability of the watchdog enable signal, reduce the noise in the third circuit, and improve the reliability of the burning interface circuit.

[0017] In some possible implementations, the resistance of the first pull-up resistor may be greater than or equal to 100,000 ohms.

[0018] In some possible implementations, the MCU may further include a seventh pin, which may be used for input and output of serial data; the programming interface may further include an eighth pin, which may be used for input and output of serial data; and the programming interface circuit may further include a fourth circuit, which is used to connect the seventh pin and the eighth pin.

[0019] For example, taking the burning interface circuit 10 as an example, in the burning interface circuit 10, the MCU may include a pin 4, the burning interface J1 may include a pin 5, and the pin 4 of the MCU may be electrically connected to the pin 5 of the burning interface J1.

[0020] In some possible implementations, the resistance value of the first resistor may be greater than or equal to 1 kilo-ohm, and / or the resistance value of the second resistor may be greater than or equal to 10,000 ohms.

[0021] In the present application, the resistance values ​​of the first resistor and the second resistor are reasonably set to improve the reliability of the programming interface circuit.

[0022] In some possible implementations, the watchdog chip may be used to set the WDI pin to a high impedance state when the fourth pin and the sixth pin of the MOS tube are disconnected.

[0023] In a second aspect, an electronic device is provided. The electronic device may include the burning interface circuit in the first aspect and any possible implementation manner thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of a watchdog circuit provided in an embodiment of the present application;

[0025] Figure 2 It is a structural schematic diagram of a burning interface circuit provided in an embodiment of the present application;

[0026] Figure 3 It is a structural schematic diagram of another burning interface circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0027] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0028] Electronic devices are widely used in all walks of life. For electronic devices equipped with processing units such as MCU and single-chip microcomputer, when subject to external interference, the processing unit may have a situation where the program runs away and falls into an infinite loop, which in turn causes the entire system to stagnate. By setting a watchdog circuit, the normal operation of the system can be guaranteed. When the processing unit is working normally, it can output a dog feeding signal at regular intervals and perform the dog feeding operation; when the processing unit fails, since the dog feeding signal cannot be obtained, the watchdog timer will time out and trigger the output of a reset signal, which can be used to restart the above-mentioned processing unit.

[0029] During the burning and debugging process, the processing unit may not output the dog feeding signal, and the feeding operation of the watchdog may be interrupted. Since the dog feeding signal is not obtained, the watchdog will mistakenly believe that the processing unit is not working properly, and then output a reset signal to restart the processing unit; this leads to the interruption of the burning and debugging process.

[0030] The burning process refers to the process of transmitting the programmed program and instructions to the processing unit through the interface specified by the manufacturer based on the programming protocol specified by the manufacturer, and the processing unit storing the program in its own memory.

[0031] For example, by adopting the watchdog disabling mechanism, the interruption of the programming process caused by the watchdog outputting a reset signal can be avoided. For example, when the pin of the watchdog circuit for receiving the dog feeding signal is in a high impedance state, it can be considered that the watchdog circuit is not connected to the processing unit; in this scenario, even if the timer times out, the watchdog will not output a reset signal. Figure 1 Provide explanation.

[0032] For example, Figure 1Schematic diagram of a watchdog circuit provided in an embodiment of the present application. Figure 1 As shown, the watchdog chip U1 is used to provide a watchdog function for the MCU.

[0033] like Figure 1 As shown, the watchdog chip U1 may include pin 1 and pin 2. Among them, pin 1 of U1 may be used to receive a dog feeding signal; it may also be called a watchdog timer input (WDI) pin. Pin 2 of the watchdog chip U1 may be used to output a reset signal; it may also be called a reset (RESET) pin.

[0034] The MCU may include a pin 1 and a pin 2; the pin 1 of the MCU may be used to output a dog feeding signal, and the pin 2 of the MCU may be used to receive a reset signal.

[0035] In some embodiments, the watchdog chip U1 and / or the MCU may include other pins. For example, the watchdog chip U1 may also include one or more of a VCC pin, a ground (GND) pin, and a manual reset (MR) pin. For another example, the MR pin of the watchdog chip U1 may be connected to a test point TP, and a manual reset signal may be input at the test point TP to implement a manual reset of the watchdog chip U1.

[0036] It is understandable that in some possible implementations, the position relationship of each pin of the watchdog chip may be Figure 1 The methods shown are different. For the functions and uses of the watchdog chip and each pin of the MCU, please refer to the relevant technical content.

[0037] like Figure 1 As shown, the WDI pin of the watchdog chip U1 can be connected to the pin 1 of the MCU through circuit #1; thus, the watchdog chip U1 can receive the dog feeding signal output by the MCU. The RESET pin of the watchdog chip U1 can be connected to the pin 2 of the MCU through circuit #2; thus, the MCU can receive the reset signal output by the watchdog chip U1.

[0038] Resistor 1 may be provided in circuit #1. For example, after removing resistor 1 from circuit #1, the WDI pin of U1 will be in a high impedance state; at this time, the watchdog function will be in a disabled state. For another example, after soldering resistor 1 back to circuit #1, the watchdog function will be in an enabled state. In the disabled state, the watchdog chip U1 will not output a reset signal even if the timer times out; while in the enabled state, the watchdog chip U1 will output a reset signal when the timer of the watchdog function times out.

[0039] for Figure 1For the solution, by removing or connecting resistor 1, the WDI pin of the watchdog chip U1 can be placed in or released from high impedance state, thereby achieving the purpose of disabling or enabling the watchdog function. When debugging the MCU, it is often necessary to remove and connect resistor 1 multiple times. On the one hand, the debugging process is too inefficient; on the other hand, constantly removing and welding resistor 1 will cause the circuit to have poor reliability.

[0040] In view of this, the embodiments of the present application provide a burning interface circuit and an electronic device, which can realize the disabling and enabling of the watchdog function without changing the hardware structure of the watchdog circuit, and can realize the smooth progress of the burning process.

[0041] For example, Figure 2 1 is a schematic diagram of a programming interface circuit provided in an embodiment of the present application. The programming interface circuit 10 may include a watchdog chip U1, an MCU, a programming interface J1 and a MOS tube Q1.

[0042] The watchdog chip U1 may include a WDI pin and a RESET pin. The MCU may include pin 1 and pin 2. For the functions of the WDI pin and the RESET pin of U1, and the functions of the pin 1 and the pin 2 of the MCU, please refer to Figure 1 The relevant records will not be repeated here.

[0043] The programming interface J1 may include pin 1 and pin 2. Among them, pin 1 may also be called a watchdog enable pin; pin 2 may be used for grounding. The watchdog enable pin may also be recorded as a WD_EN pin; the signal transmitted through the pin may be recorded as a WD_EN signal; the WD_EN signal may include a high level state and a low level state.

[0044] The MOS tube Q1 may include pin 1, pin 2 and pin 3. Among them, the pin 1 of the MOS tube Q1 can be connected to the WDI pin of the watchdog chip U1 through a circuit. The pin 2 of the MOS tube Q1 can be connected to the watchdog enable pin of the burning interface J1 through a circuit. The pin 3 of the MOS tube Q1 can be grounded.

[0045] Exemplarily, the burning interface circuit 10 may further include a first circuit, a second circuit and a third circuit.

[0046] The first circuit can be used to connect the RESET pin of the watchdog chip U1 and the pin 2 of the MCU; through the first circuit, the MCU can receive the reset signal output by the watchdog chip U1. For example, the first circuit can correspond to Figure 1 Circuit #2 in .

[0047] The second circuit may include a first branch and a second branch. The first branch and the second branch are provided with a connection point at one end of the WDI pin of the watchdog chip U1. The first branch may be used to connect the WDI pin of the watchdog chip U1 and the pin 1 of the MCU. The second branch may be used to connect the WDI pin of the watchdog chip U1 and the pin 1 of the MOS tube Q1. A first resistor may be provided on the first branch, and a second resistor may be provided on the second branch. For example, the first branch may correspond to Figure 1 Circuit #1 in Figure 1 The resistor 1 in can correspond to the first resistor.

[0048] The third circuit can be used to connect the watchdog enable pin of the programming interface J1 and the pin 2 of the MOS tube Q1.

[0049] The programming interface circuit 10 can be used to enable the watchdog chip U1 to output a reset signal according to the connection state between pin 1 and pin 2 of the programming interface J1. In other words, the programming interface circuit 10 can enable / disable the watchdog function by adjusting the connection state between pin 1 and pin 2 of the programming interface J1.

[0050] Exemplarily, when pin 1 and pin 2 of the burning interface J1 are disconnected, the burning interface circuit 10 can allow the watchdog chip to output a reset signal; and when pin 1 and pin 2 of the burning interface J1 are short-circuited, the watchdog chip no longer outputs a reset signal.

[0051] That is to say, when pin 1 and pin 2 of the burning interface J1 are disconnected, the watchdog function can be enabled; the watchdog chip U1 can feed the dog according to the feeding signal and output a reset signal when the MCU fails. When pin 1 and pin 2 of the burning interface J1 are connected, the watchdog function will be disabled; the watchdog chip U1 will no longer output a reset signal.

[0052] In some embodiments, when the MCU needs to be burned, the external interface can be connected to the burning interface J1. Through the external interface, on the one hand, the MCU can be burned, and on the other hand, pin 1 and pin 2 of the burning interface J1 can be short-circuited; thereby, the watchdog function can be disabled. In normal use scenarios, there is no need to use the external interface; pin 1 and pin 2 of the burning interface J1 are in a disconnected state, so that the watchdog chip can output a reset signal to the MCU when it fails. In other words, the disabling and enabling of the watchdog function can be achieved only by connecting or disconnecting the external interface and the burning interface J1.

[0053] In the embodiment of the present application, it is possible to meet different requirements for the watchdog function in different scenarios such as normal use and burning without changing the hardware structure of the circuit used to transmit the dog feeding signal, thereby improving debugging efficiency and ensuring circuit reliability.

[0054] Exemplarily, the watchdog chip U1, MCU and / or burning interface J1 may also include other pins. For example, the MCU may also include pins 3 and 4; pin 3 of the MCU may be used for the input and output of serial data, and the pin 3 may also be referred to as a serial data input and output (SWDIO) pin, and the signal transmitted through the pin may be referred to as a SWDIO signal; pin 4 of the MCU may be used for the transmission of the clock signal of the serial line, and the pin 4 may also be referred to as a serial wire clock (SWCLK) pin, and the signal transmitted through the pin may be referred to as a SWCLK signal. For another example, the burning interface J1 may also include one or more of pins 3, 4, 5 and 6. Among them, pin 3 may be used to connect to VCC, pin 4 may be used for the input and output of serial data (i.e., for the transmission of SWDIO signals), pin 5 may be used for the transmission of the clock signal of the serial line (i.e., SWCLK signals), and pin 6 may be used for the transmission of other signals (such as an indication signal indicating the reset of the watchdog chip in a test scenario). For another example, pin 4 of the burning interface J1 can be electrically connected to pin 3 of the MCU to achieve transmission of serial data between the two; pin 5 of the burning interface J1 can be electrically connected to pin 4 of the MCU to achieve transmission of the clock signal of the serial line.

[0055] Exemplarily, for the MOS tube Q1, its pin 2 can be located at the gate of the MOS tube. Assume that the MOS tube Q1 is an N-channel MOS tube. For example, when pins 1 and 2 of the burning interface J1 are short-circuited, the third circuit can be at a low level, that is, the WD_EN signal can be in a low level state; since pin 3 of the MOS tube is grounded, pins 1 and 3 of the MOS tube Q1 will be disconnected. For another example, when pins 1 and 2 of the burning interface J1 are disconnected, the third circuit can be at a high level, that is, the WD_EN signal can be in a high level state; since pin 3 of the MOS tube is grounded, pins 1 and 3 of the MOS tube Q1 will be turned on.

[0056] In some possible implementations, the programming interface circuit 10 may further include a TVS tube, one end of which may be grounded, and the other end of which may be connected to the third circuit.

[0057] In the embodiment of the present application, by providing the TVS tube, the instantaneous overvoltage of the third circuit can be suppressed, which is beneficial to ensure that the MOS tube works in an expected manner.

[0058] In some possible implementations, the programming interface circuit 10 may further include a first pull-up resistor, one end of which may be connected to the third circuit. For example, the resistance of the first pull-up resistor may be greater than or equal to 100,000 ohms.

[0059] In the embodiment of the present application, by setting the first pull-up resistor, it is helpful to ensure the stability of the watchdog enable signal, reduce the noise in the third circuit, and improve the reliability of the burning interface circuit.

[0060] In some possible implementations, the resistance of the second resistor may be greater than or equal to 10,000 ohms.

[0061] When pins 1 and 3 of the MOS tube Q1 are turned on, if the resistance of the second resistor is small, the current in the second branch may be relatively large. In the embodiment of the present application, the resistance of the second resistor is reasonably set to avoid damage to the MOS tube Q1 due to excessive current in the second branch, thereby improving the reliability of the programming interface circuit.

[0062] In some possible implementations, the resistance of the first resistor may be greater than or equal to 1 kiloohm.

[0063] In some possible implementations, the watchdog chip U1 can be used to set the WDI pin to a high impedance state when the pin 1 and the pin 3 of the MOS tube Q1 are disconnected. For example, when the pin 1 and the pin 3 of the MOS tube Q1 are connected and disconnected, the external circuit of the WDI pin can have different electrical characteristics; according to the electrical characteristics, it can be known whether the pin 1 and the pin 3 of the MOS tube Q1 are disconnected.

[0064] Exemplarily, the high impedance setting of the WDI pin can be implemented by software. For example, assuming that the watchdog chip U1 will disable the watchdog function when its WDI pin is in a high impedance state; when it is determined that pin 1 and pin 3 of the MOS tube Q1 are disconnected, the output of the reset signal can be stopped by software; in terms of external performance, when pin 1 and pin 3 of the MOS tube Q1 are disconnected, the WDI pin of the watchdog chip is in a high impedance state.

[0065] Combination of the above Figure 2 The programming interface circuit of the embodiment of the present application is exemplarily described. Figure 3 Another programming interface circuit 20 provided in an embodiment of the present application is exemplarily described. The programming interface circuit 20 can be understood as an extension or deformation of the programming interface circuit 10 .

[0066] For example, Figure 3 Schematic diagram of the programming interface circuit 20 provided in an embodiment of the present application.

[0067] like Figure 3 As shown, in the programming interface circuit 20, the watchdog chip U28 can correspond to Figure 2 The watchdog chip U1 in the MCU. The WDI pin of the watchdog chip U28 can be used to receive the dog feeding signal; the RESET pin of the watchdog chip U28 can be used to output a reset signal to reset the corresponding MCU.

[0068] In the programming interface circuit 20, the programming interface J5 may correspond to Figure 2 The burning interface J1 in the programming interface. Pin 5 of the burning interface J5 is grounded; Pin 6 of the burning interface J5 is the watchdog enable pin.

[0069] like Figure 3 As shown, the MOS transistor Q35 in the burning interface circuit 20 can correspond to the MOS transistor Q1 in the burning interface circuit 10; the resistor R174 in the burning interface circuit 20 can correspond to the first resistor in the burning interface circuit 10; the resistor R175 in the burning interface circuit 20 can correspond to the second resistor in the burning interface circuit 10; the resistor R176 in the burning interface circuit 20 can correspond to the first pull-up resistor in the burning interface circuit 10; the TVS tube D16 in the burning interface circuit 20 can correspond to the TVS tube in the burning interface circuit 10 connected to the third circuit.

[0070] In the programming interface circuit 20, the programming interface J5 may correspond to Figure 2 The burning interface J1 in the circuit 11 can correspond to Figure 2 The first circuit in; Circuit 12 may correspond to Figure 2 The first branch of the second circuit in; Circuit 13 may correspond to Figure 2 The second branch of the second circuit in the circuit 14 may correspond to Figure 2 The third circuit in.

[0071] Different from the programming interface circuit 10, in the programming interface circuit 20, the circuit 11 may include a plurality of MOS transistors (such as MOS transistors Q33 and Q34) and a plurality of pull-up resistors (such as resistors R170, R171 and R173). Figure 3 The dotted line frame portion of the circuit 11 in the middle. The circuit connected to pins 2 to 4 of the programming interface J5 may be provided with multiple pull-up resistors (such as resistors R177, R178 and R179), refer to Figure 3 The dotted line frame portion of the programming interface J5. A resistor R172 is provided in the circuit connected to the VCC pin of the watchdog chip U28.

[0072] The resistance values ​​of each resistor and the capacitance values ​​of each capacitor in the programming interface circuit 20 can be referred to Figure 3 As shown. It is understandable that Figure 3 The resistance values ​​of the resistors and the capacitance values ​​of the capacitors shown are only examples and can be adjusted and adapted according to actual needs, and the embodiments of the present application are not limited to this.

[0073] The following is an exemplary description of the working mode of the programming interface circuit 20 in different scenarios.

[0074] In the early debugging stage, even if the watchdog signal has not been developed, by shorting pins 5 and 6 of the burning interface J5, pins 1 and 3 of the MOS tube Q35 can be turned on. In this case, pin 4 of the watchdog chip U28 is electrically suspended, and the watchdog function is disabled, which enables free opening and debugging of the software.

[0075] In the working scenario, the MCU can output a dog feeding signal. When the MCU works abnormally and cannot perform the dog feeding operation, the watchdog function of the watchdog chip U28 will trigger a reset signal to reset the MCU.

[0076] When burning is required, the burning interface J5 can be connected to a burning device such as a burner, and pins 5 and 6 of the burning interface J5 can be short-circuited. In this scenario, the watchdog function is disabled, and the MCU can download normally; even if the MCU does not output a dog-feeding signal, the watchdog chip U28 will not output a reset signal to reset the MCU. For the burning interface circuit 20, the download will not be interrupted due to the MCU not outputting a dog-feeding signal.

[0077] Combination of the above Figures 2 to 3 The burning interface circuit provided in the embodiment of the present application is exemplarily described.

[0078] The present application also provides an electronic device, which may include the above Figure 2 or Figure 3 The burning interface circuit in.

[0079] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0080] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0081] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0082] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0083] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0084] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A programming interface circuit, characterized in that: The programming interface circuit includes: a watchdog chip, a microprocessor unit MCU, a programming interface and a MOS tube. The watchdog chip comprises: a watchdog input WDI pin and a reset RESET pin, wherein the WDI pin is used to receive a watchdog feeding signal, and the RESET pin is used to output a reset signal, wherein the watchdog feeding signal is used to indicate that the MCU is working normally, and the reset signal is used to indicate that the MCU is reset; The MCU comprises: a first pin and a second pin, the first pin is used to output the dog feeding signal, and the second pin is used to receive the reset signal; The programming interface includes: a watchdog enable pin and a third pin for grounding; The MOS tube comprises: a fourth pin, a fifth pin, and a sixth pin for grounding; The programming interface circuit also includes: a first circuit, a second circuit and a third circuit; The first circuit is used to connect the RESET pin and the second pin; The second circuit includes a first shunt and a second shunt, the first shunt is used to connect the WDI pin and the first pin; the second shunt is used to connect the WDI pin and the fourth pin, the first shunt and the second shunt are provided with a connection point at one end close to the WDI pin, the first shunt is provided with a first resistor, the second shunt is provided with a second resistor, and the first resistor is smaller than the second resistor; The third circuit is used to connect the watchdog enable pin and the fifth pin; The watchdog chip is used for: not outputting the reset signal when the watchdog enable pin and the third pin are short-circuited; and outputting the reset signal according to the watchdog feeding signal when the watchdog enable pin and the third pin are disconnected.

2. The programming interface circuit according to claim 1, characterized in that: When the watchdog enable pin and the third pin are short-circuited, the fourth pin and the sixth pin of the MOS tube are disconnected; or, When the watchdog enable pin and the third pin are disconnected, the fourth pin and the sixth pin of the MOS tube are turned on.

3. The programming interface circuit according to claim 1 or 2, characterized in that: The programming interface circuit further includes a transient voltage suppression TVS tube, one end of the TVS tube is grounded, and the other end of the TVS tube is connected to the third circuit.

4. The programming interface circuit according to claim 1 or 2, characterized in that: The programming interface circuit further includes a first pull-up resistor, one end of which is connected to the third circuit.

5. The programming interface circuit according to claim 4, characterized in that: The resistance of the first pull-up resistor is greater than or equal to 100,000 ohms.

6. The programming interface circuit according to claim 1 or 2, characterized in that: The MCU further includes a seventh pin, and the seventh pin is used for inputting and outputting serial data; The programming interface further includes an eighth pin, and the eighth pin is used for inputting and outputting serial data; The programming interface circuit further includes a fourth circuit, and the fourth circuit is used to connect the seventh pin and the eighth pin.

7. The programming interface circuit according to claim 1 or 2, characterized in that: The resistance value of the first resistor is greater than or equal to 1 kilo ohm, and / or the resistance value of the second resistor is greater than or equal to 10,000 ohms.

8. The programming interface circuit according to claim 1 or 2, characterized in that: The watchdog chip is used for: When the fourth pin and the sixth pin of the MOS tube are disconnected, the WDI pin is set to a high impedance state.

9. An electronic device, characterized in that: The electronic device comprises the burning interface circuit according to any one of claims 1 to 8.

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