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Some problems about stm32 driving matrix keyboard and alternative methods of matrix keyboard About matrix keyboard For general buttons, I generally prefer interrupt mode to trigger. One is to save the resources of single chip microcomputer without having to scan it back and forth. Second, the interrupt is very efficient and easy to handle. Bu ...

1. Problem description Independent variables: the influencing factors of the optimal distillation structure are the feed composition A, B, C, the ratio of relative volatility ESI, and the separation requirements GESI, where A+B+C=1, so the degrees of freedom of the five independent variables are 4. Dependent variable: there are 7 kinds of thr ...

Aggregate query Aggregate query refers to the statistical query of part or all of the data of a field in a data table. Aggregate query is required to query the average price of all books in the book data table and the total number of all books. Whole table aggregation Import method: from django.db.models import* Aggregate function: Sum, Avg, ...

Future (asynchronous operation)   Future has three statuses: unfinished, completed with value and completed with exception. Using future can simplify event tasks. In Dart, future objects can be used to represent the results of asynchronous operations. The return type of future is future < T > There are three ways to deal with the ...

Note: This is a machine learning practical project (with data + code). If you need data + complete code, you can get it directly at the end of the article. 1. Project background         For the fault diagnosis of semiconductor etcher, it is necessary to collect and obtain the data of the etching process o ...

import hue.edu.xiong.volunteer_travel.core.Result; import hue.edu.xiong.volunteer_travel.core.ResultGenerator; import hue.edu.xiong.volunteer_travel.model.*; import hue.edu.xiong.volunteer_travel.service.SystemService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.domain.Page; import org.sp ...

preparation Intranet environment deployment project, the configuration environment is cumbersome. Use the docker import / export image and container function to create and export the project environment on the networked server, and then import it directly on the intranet server. Offline installation 1. Download docker installation package Do ...

1, Introduction to c language helloworld 1. Open the terminal under ubuntu system 2. Find the appropriate location and create a new folder helloworld. mkdir helloworld 3. Open the helloworld folder cd helloworld As shown in the figure 4. Create and open a c language file named hello.c with vim vi hello.c 5. Enter the following ...

PS: I have a list to answer, Click here to add me preface 1. As early as mid August, I received a fan who said that there was a development demand. Come to me to talk about whether it could be realized 2. It's really done, but because the money came from a little dark, they didn't take it in the end, and the other party didn't take it ...

1. Simple factory mode   1.1 meaning The simple factory pattern is also called the static method pattern (because the factory class defines a static method)In real life, factories are responsible for producing products; Similarly, in the design pattern, the simple factory pattern can be understood as a class responsible for production obj ...