A HMI connects four PLC with the same parameters (19200, N, 8, 2) through COM2 port RTU485. Because it is one-to-many, I use for loop to traverse four PLC to read variables. You only need to set the station number. by monitoring a second variable insi...
client initiates tcp connection con1:Aip: Aport- > Bip:Bport, does not have a problem, do not close the connection, initiate tcp connection con2:Aip:Aport- > Cip:Bport, will address already in use, according to the quad, the two connections are not the ...
problem description the iis7.5 80 port that the server is running is unmodifiable apache2.4 8080 port runs other services now it has done iis redirection to www.b.com--> www.b.com:8080 now access always has 8080 port number apache how to hide the ...
The default port of the page that pops up after 1, npm install-g create-react-app 2, create-react-app my-app 3, cd my-app 4, npm start is 3000. How to modify the default port? The server is not under the premise of this port number. Added: to packa...
give an example, the local client accesses the remote mysql server 3306 port. requires access to remote port 3306. my question is: does the network of the local client need to apply? Local access to remote port 3306, which port is used by the local...
questions you want to answer: Why can t the call method be called through apply ? Why is the second and third output -Infinity ? Why does the Reflect object provide only the apply method and not the call method? I don t know if my ...
error report: Access to Image at https: img.codeshelper.com upload img 2021 03 13 uef0t21ij4j7750 "http: xxx.yyyyyyyy.com app package 2ec8bab90c794f208b6c2137a50dd9db.png " rel= " nofollow noreferrer "> http: xxx.yyyyyyyy.com app p. from origin...
in MFC development, how to change the picture content of pictureBox by clicking a button? this property in pictureBOX: how to add code to the button to make pictureBOX load another picture when you click the button, thank you! ...
problem description I found two ways to write const on the Internet. why is one reporting an error while the other is successful? ...
for example, when I upload a picture, I can edit the picture and get a box where I can add text directly to the picture and upload it to the backend how do I do this? (big guys help) are there any cases? I ve been looking for it for a long time bu...