Hi Team, We have the controller AXC F 1152 with a little program. Now we want to write a little error log into a text file. I need some help how I can write the code therefore. Maybe someone was creating something like this before and can give some tipps. Thanks & BR Bodo
Hi Bodo, Here is an example of how to write text to a file in in PLCnext Engineer. https://www.plcnext-community.net/en/discussions-2-offcanvas/example-for-saving-data-in-a-file.html The example uses Structured Text, but you can use the same FBs in other IEC 61131 languages, if you want. Hope this helps. ~ Martin.
Hi Martin, what a great and very fast solution. I’ve tried the code and it works fine. 
I have an other question. It is possible to write the file on a local PC System or maybe on file server? BR Bodo
Hi Bodo, I don’t think there is a standard solution to this problem from PLCnext Engineer on its own, but this could probably be achieved using standard Linux utilities. Possibilites include:
* Using rsync to copy the contents of local file(s) to a remote machine. * Using syslog-ng for decentralised system logging. * Using a cloud service to log messages (via MQTT, for example). * Looking for solutions from vendors in the PLCnext Store.You should be able to try most options on a standard Linux system, and once you have a solution working the way you want, you can try porting that solution to the PLCnext Control. Hope this helps. ~ Martin.
Hi Martin, Thanks again for your support. I have a last question fot this topic. How can collect a String (‘hello World’) with the actual date? Do you have an idea. BR Andy
Hi Andy, There is a function block called “RTC_S” that retrieves the current date and time as a string. ~ Martin.
Hi Martin, I have a last question (hope so). In your example : https://www.plcnext-community.net/en/discussions-2-offcanvas/example-for-saving-data-in-a-file.html I work with a ByteArray35 and if I understand right, that means no more characters like 34. Now I need the oppertunity for more characters - is this possible? Thanks Andy
Hi Andy, I only used ByteArray35 in that example because that was already a defined data type in PLCnext Engineer. But you can use a byte array of any length. To do that:
* In a DataType worksheet, create a new data type as a byte array of any fixed length (the declaration templates - accessible using right-click - are handy for this). * In your program, declare a variable of that type, instead of type ByteArray35.Hope this helps. ~ Martin.
Hi Martin, sounds good, but I need more help. Did you have a short example for me? Thanks a lot for your support. BR
Andy
Hi Andy, Hope this helps. (video has no sound) Note that the array actually contains 421 elements (0 to 420), so I could have called it ByteArray421, or else declared the array bounds as either [0 .. 419] or [1 .. 420]. ~ Martin.
Hi Martin, That’s great - it works fine. ? Thank you so much for your help. BR
Andy
Hi Martin, Can I get that sample code? I want to do test with PLCnext 2152. Thank you, Jacob
Hi Jacob, unfortunately this new forum has broken all the links to old threads, and deleted all the attachments on those old threads. For the record, here is the new link to the old thread mentioned above: https://www.plcnext-community.net/forum/#/discussion/1446/example-for-saving-data-in-a-file … but of course since the attachments are gone, that doesn’t help. On Monday I will see if the site admins can restore the old attachments, otherwise I will try to recreate the example.
OK, the admins are looking at the option of restoring images in old forum posts. Here are the details of the earlier example, which writes a string to a text file on the PLC’s file system: Program variables: // Name Type FILE_OPEN1 FILE_OPEN STRING_TO_BUF1 STRING_TO_BUF FILE_WRITE1 FILE_WRITE FILE_CLOSE1 FILE_CLOSE OpenCommand BOOL CreateByteArray BOOL WriteCommand BOOL CloseCommand BOOL FileHandle UINT StringToWrite STRING NumChars INT CharsToWrite ByteArray35 Program code: // Here is the string we will write to file. StringToWrite := 'hello world'; NumChars := LEN(StringToWrite); // Go online, open this program instance and // set OpenCommand to TRUE. // This will open the file. FILE_OPEN1( Execute := OpenCommand, Name := '/opt/plcnext/my-file.txt', Done => CreateByteArray, // Immediately create the byte array when the OPEN command is finished. Handle => FileHandle // We need the file handle for other operations on this file. ); // Convert the string to an array of bytes STRING_TO_BUF1( REQ := CreateByteArray, BUF_CNT := NumChars, DONE => WriteCommand, // Immediately set WriteCommand when the buffer is ready. SRC := StringToWrite, BUFFER := CharsToWrite ); // Add CR LF to the end of the string, just for the craic. CharsToWrite[NumChars] := BYTE#16#D; // CR = 0x0D CharsToWrite[NumChars+1] := BYTE#16#A; // LF = 0x0A // Write the array of bytes to file FILE_WRITE1( Execute := WriteCommand, Handle := FileHandle, Done => CloseCommand, // Immediately set CloseCommand when the file write is finished. Buffer := CharsToWrite, Length := NumChars + 2 // Remember CR LF ! ); // Close the file FILE_CLOSE1( Execute := CloseCommand, Handle := FileHandle ); // Now use ssh (or PuTTY) to check that the file has been created, and that it contains the expected text.
Hi Martin, I found “Data Logger” library on PLCnext store and it’s working well. Also I tested the example code. Thank you, Jacob
Great, thanks for the feedback. If you’re interested in the Datalogger library, you might also want to look at: - Simple Logger, which (as the name suggests) is a simpler version of the DataLogger library. - The built-in DataLogger, which stores data in a SQLite database rather than a text file. These are each useful for different scenarios, so hopefully one suits your project. -
OK, the admins are looking at the option of restoring images in old forum posts.
\nHere are the details of the earlier example, which writes a string to a text file on the PLC’s file system:
\nProgram variables:
\/\/ Name Type
\nFILE_OPEN1 FILE_OPEN
\nSTRING_TO_BUF1 STRING_TO_BUF
\nFILE_WRITE1 FILE_WRITE
\nFILE_CLOSE1 FILE_CLOSE
\nOpenCommand BOOL
\nCreateByteArray BOOL
\nWriteCommand BOOL
\nCloseCommand BOOL
\nFileHandle UINT
\nStringToWrite STRING
\nNumChars INT
\nCharsToWrite ByteArray35\n</pre>\n
> \nProgram code: > \/\/ Here is the string we will write to file.
\nStringToWrite := ‘hello world’;
\nNumChars := LEN(StringToWrite);
\n
\n// Go online, open this program instance and
\n// set OpenCommand to TRUE.
\n// This will open the file.
\nFILE_OPEN1(
\n Execute := OpenCommand,
\n Name := ‘/opt/plcnext/my-file.txt’,
\n Done => CreateByteArray, // Immediately create the byte array when the OPEN command is finished.
\n Handle => FileHandle // We need the file handle for other operations on this file.
\n);
\n
\n// Convert the string to an array of bytes
\nSTRING_TO_BUF1(
\n REQ := CreateByteArray,
\n BUF_CNT := NumChars,
\n DONE => WriteCommand, // Immediately set WriteCommand when the buffer is ready.
\n SRC := StringToWrite,
\n BUFFER := CharsToWrite
\n);
\n
\n// Add CR LF to the end of the string, just for the craic.
\nCharsToWrite[NumChars] := BYTE#16#D; // CR = 0x0D
\nCharsToWrite[NumChars+1] := BYTE#16#A; // LF = 0x0A
\n
\n// Write the array of bytes to file
\nFILE_WRITE1(
\n Execute := WriteCommand,
\n Handle := FileHandle,
\n Done => CloseCommand, // Immediately set CloseCommand when the file write is finished.
\n Buffer := CharsToWrite,
\n Length := NumChars + 2 // Remember CR LF !
\n);
\n
\n// Close the file
\nFILE_CLOSE1(
\n Execute := CloseCommand,
\n Handle := FileHandle
\n);
\n
\n// Now use ssh (or PuTTY) to check that the file has been created, and that it contains the expected text.\n</pre>\n
How can i test the programm with putty? what is the needed configuration? > [putty.PNG](https:\\/\\/forum.plcnext-community.net\\/uploads\\/VUHLE8HHJ0XA\\/putty-png.png)Thank you. >
Hi Martin,<\/p>\nI have a last question (hope so).<\/p>\nIn your example : [https:\/\/www.plcnext-community.net\/en\/discussions-2-offcanvas\/example-for-saving-data-in-a-file.html<\/a><\/p>\nI work with a ByteArray35 and if I understand right, that means no more characters like 34.<\/p>\nNow I need the oppertunity for more characters - is this possible?<\/p>\nThanks<\/p>\nAndy<\/p>file path '/opt/plcnext/my-file.txt' can be changed or not?
[https://forum.plcnext-community.net/discussion/comment/6379#Comment_6379</a></p>
file path '\/opt\/plcnext\/my-file.txt' can be changed or not? \n<\/pre>Yes, the NAME parameter on the FILE_OPEN function block takes a STRING as a parameter, and this can be a literal or a variable. >
[https:\/\/forum.plcnext-community.net\/discussion\/comment\/9795#Comment_9795<\/a><\/p>How can i test the programm with putty? what is the needed configuration?<\/p>[https:\/\/forum.plcnext-community.net\/uploads\/VUHLE8HHJ0XA\/putty-png.png<\/a><\/p>Thank you.<\/p>(better late than never?) > In the window shown in the screen shot, just enter the IP address of the PLC, and press the "Open" button. It should ask for the username and password, which are the same as the ones you used to send the PLCnext Engineer project to the PLC. >