The relay programming controls why the software system is reset

You can return the PC pointer to the original position of the program. At the same time, the RAM area and registers are cleared, and the reset is realized.

Some systems allow reset, but there are special requirements for peripherals: a certain IO state cannot be changed due to reset, a certain timer counter cannot be changed, etc.

Example: System A controls the power supply of system B through an IO, and the power of system B is turned on when the IO is set high.

In the normal working process, system B will only shut down when it receives the shutdown command task of system A (that is to say, it cannot be powered off and shut down), and system A needs to reset during the working process.

In this case, if the conventional reset method is used, the IO will be reset, which does not meet the requirements. It would be nice if there was a way to just reset the kernel and not the peripherals.

Next, we will introduce two ways to implement reset.

2 About reset.

When it comes to reset, we are all familiar with it, and the system basically has a reset button.

There are many types of resets: power-on reset, power-down reset, reset pin reset, watchdog reset, software reset, etc.

The reset button mentioned above is the corresponding reset pin reset; The kernel reset and system reset mentioned in this article belong to software reset.

3 Difference Between Kernel Reset and System Reset.

The cores mentioned in this article refer to the processor cores, that is, the microprocessor unit (MPU). For example, the core of STM32F103 is the Cortex-M3 core.

The system here contains the kernel and peripherals, that is, the MCU (Microcontroller Unit), for STM32F103, it is the Cortex-M3 core + various peripheral interfaces.

Core Reset: Only resets the Cortex-M3 processor, not the registers of peripherals such as GPIO, TIM, USART, SPI, etc.

System Reset: Resets the Cortex-M3 processor and resets the peripheral registers.

Therefore, when we talk about reset, we generally refer to system reset.

4 Function sources for kernel reset and system reset**.

In this article, Cortex-M3 (STM32F103) is used as an example to illustrate that other chips are similar.

Purpose:1 Causes the CPU to run from the initial instruction.

2 Make all parts of the system run in sync.

In the operation of programmable chips (such as single-chip microcomputers), programmable controllers (PLCs), microcomputers and other electronic equipment, there will be a situation where the program flies or the program jumps, and the specific interface of the hardware can be sent to the hardware by manual or automatic methods to restore the operation of the software to a specific program segment, which is the reset process; In this process, the signal sent to a specific interface of the hardware by manual or automatic methods is the reset signal.

Reset is reset. It serves two purposes:

One is to make the CPU run from the initial instruction.

The other is to make the parts of the system run in sync.

During power-on or reset, control the reset state of the CPU: keep the CPU in the reset state during this time, instead of being on it once.

It can also improve electromagnetic compatibility performance by preventing the CPU from issuing wrong instructions and performing wrong manipulation.

The so-called reset circuit is to use it to restore the circuit to the starting state. Just like the function of the calculator's reset button, when you finish the calculation of a problem, you must clear it! Or if you make a mistake or make a miscalculation, you have to clear the operation.

In order to go back to the original state and recalculate. Unlike the calculator reset button, the means of starting the reset circuit are different. First, the reset operation is carried out immediately when the circuit is energized; Second, it can be operated manually when necessary; The third is to carry out automatically according to the needs of the program or circuit operation.

Usurper circuits are relatively simple, and most of them can be done with only a combination of resistors and capacitors. No matter how complicated it is, there are triodes and so on.

Hardware reset: As the name suggests, the system is reset through hardware, such as designing a reset circuit on the circuit board, and the system can be reset by pressing the button, regardless of what kind of program the system is executing.

Soft reset: The reset operation is achieved by giving the system a reset signal through software, such as a low level or a high level (depending on the system settings).

Power-on reset: The system performs a reset operation at the moment of power-on.

What kind of reset to perform depends on the need.

This is very simple, the switch is connected to an input port, and the counter is used on the port, when the count value is 1, there is an output, and when the count value is 2, the counter is reset.

Your output port should be the output port of the relay, just program the relay port and you can do it.

After a closer look at your problem, it should be to control the opening and closing of a port with two inputs.

It should be enough to talk about two control points and get up together.

The switch has a rising edge pulse, and it would be nice to add a time relay interlock... Internet speed card,The programmed program can't be uploaded.。。。 Or I'll send it to you.

Input point differential pulse rising edge, using a holding type relay

Relay (English name: relay) is an electrical control device, which is an electrical appliance that makes a predetermined step change of the controlled quantity in the electrical output circuit when the change of the input quantity (excitation quantity) reaches the specified requirements. It has an interactive relationship between the control system (also known as the input loop) and the controlled system (also known as the output loop).

Usually used in the control circuit of automation, it is actually a kind of "automatic switch" that uses a small current to control the operation of a large current. Therefore, it plays the role of automatic adjustment, safety protection, and conversion circuit in the circuit.

The relay is an automatic switching element with isolation function, which is widely used in remote control, telemetry, communication, automatic control, mechatronics and power electronic equipment, and is one of the most important control components.

Relays generally have an induction mechanism (input part) that can reflect certain input variables (such as current, voltage, power, impedance, frequency, temperature, pressure, speed, light, etc.); There is an actuator (output part) that can realize "on" and "off" control of the controlled circuit; Between the input and output parts of the relay, there is also an intermediate mechanism (drive part) that couples and isolates the input quantity, processes the function, and drives the output part. - Wuhan H.V. Hipot

gdjb-1200 relay protection test set / secondary current injection test set

As far as I know, there are at least two types of relay cards, 1, relay module, that is, the relay socket that can be fixed on the rail or electric control panel, and 1-16 (or maybe more) relays can be inserted on it, and the pins are unified with binding posts or cables.

2. Relay interface card or control card, that is, a circuit board that can be inserted into the slots such as PC, industrial computer, PLC or special controller, which integrates multiple relays and has output interfaces.

There may be some unknown types, but these two types are common. Hope it helps.