Does the C51 MCU have a software watchdog? How to use it? Switching power supply, please consult

What kind of single-chip microcomputer do you use?,Now the general single-chip microcomputer has an internal hardware watchdog.,Even 8051 has it (like),But it seems to be a fixed time.,But it can also be used.,Not to mention other high-performance。 If there really isn't, there's a whole bunch of software watchdog C programs on the web.

In addition, the power supply depends on which aspect you consider. The ripple after the rectification and filtering of the transformer power supply is smaller, but the disadvantage is that the efficiency is low (it will be slightly better to use LDO, but your voltage difference is too large, 12-5=7V if the single-chip microcomputer is 5V, it is recommended to replace the AC9V transformer).

On the contrary, the switching power supply has a large ripple, generally more than 50mv, while the 78xx series is easy to achieve 10mv, but the efficiency will be relatively high, generally it should be at 80%. At the same time, if you make the circuit of the switching power supply and the weak current circuit such as the single-chip microcomputer on the same board, it will produce relatively large interference, and if you use it, you should pay attention to anti-interference measures.

It is advisable to use a transformer to generate power without emphasizing efficiency.

The above is my understanding, please forgive me if there is any inappropriateness).

It is better to change the switching power supply, the software watchdog can, make an interrupt program yourself, and you can make a soft dog by comparing the time.

Hello: The application of watchdog is mainly for special environments, and the strong magnetic field environment may make the microcontroller program run away, resulting in dysfunction, which is not expected when using the microcontroller.

With the use of the watchdog, even if the program flies away and the dog is not fed within the specified time, then the watchdog forcibly resets the single-chip microcomputer and returns to its normal working state.

What you said about the watchdog is right, if you don't feed the dog, it will overflow, and the overflow will reset the single-chip microcomputer, but you don't understand the application concept of the watchdog.

If you don't understand, you can reply to me at any time.

I hope mine can help you.

First of all, the purpose of the watchdog is to reset the system to work normally after the single-chip microcomputer program flies, and the purpose of setting the watchdog is not to ask you to trigger the watchdog, if so, then your single-chip microcomputer has been reset? How does that still work?

Secondly, if you want to check whether the watchdog can reset the system, it is recommended to use a time-delay plus LED light to observe. Judging by your question, it seems that the purpose of setting up a watchdog is to trigger the watchdog, which is not right

What logic, the watchdog should restore the initial value within a specified period of time, and this time period is determined by the microcontroller model. If the time exceeds and there is no assignment, it will overflow, that is, the system is stuck, and it will be automatically reset.