My application saves data in a .txt file. I have created a progress bar to indicate the progress of the file writing up to 100%. However, when the program runs, the screen no longer refreshes until the writing in the file is completed.
I was wondering if there is a way to give an update on the screen through a program line.
The program writes the entire file in a loop. So I made a second program option without the loop, where it writes one part at each scan, but even then the progress bar does not update. Why does this happen?

PROGRAM SALVA_LEIT_WTXT
VAR
IP: STRING := '192.168.0.1';
// TRANSITION OF START OF WRITING
TR_SSALV: R_TRIG;
Date_Time: RTCLK.GetDateAndTime;
// YEAR
ANO: UINT;
// MONTH
MES: UINT;
// DAY
DIA: UINT;
// HOUR
HORA: UINT;
// MINUTE
MINUTO: UINT;
// SECONDS
SEGUNDO: UINT;
// STRING YEAR
STR_ANO: STRING;
// STRING MONTH
STR_MES: STRING;
// STRING DAY
STR_DIA: STRING;
// STRING HOUR
STR_HORA: STRING;
// STRING MINUTE
STR_MINUTO: STRING;
sFileName: CAA.FILENAME;
// SIZE OF STRING
TAM_STR: INT;
// DATA VALUE CONVERTED TO STRING
VAL_STRING2: STRING;
// STRING OF TIME
TEMPO_STRING: STRING;
LOOP: INT;
txt_Virg: STRING := ',';
txt_Fim_Cab: STRING := '}';
txt_Tempo: STRING := 'TIME:';
txt_IP: STRING := '{IP:';
udiWriteError1 : RTS_IEC_RESULT;
udiCloseError1 : RTS_IEC_RESULT;
xText_Write: STRING(10000);
udiWrite : UDINT;
udiOpenError1 : RTS_IEC_RESULT;

hFile : RTS_IEC_HANDLE := RTS_INVALID_HANDLE;
// WRITE FILE
MESCR: BOOL;
MDATA: BOOL;
// TRANSITION OF END OF WRITING
TR2_NSSALV: F_TRIG;
LOOP2: UINT;
// PERCENTAGE OF WRITING TO PROGRESS BAR
RPERC: REAL;
// TRANSITION OF START
TR_INIC: R_TRIG;
// SAVE
SSALV: BOOL;
// TABLE OF TIMES OF DATA STORED TO WRITE TO TXT
TEMPO: ARRAY[1..10000] OF UDINT;
// STORED DATA TO WRITE TO TXT
MSG_COM: ARRAY[1..10000, 1..5008] OF BYTE;
END_VAR

// THIS PROGRAM WRITES THE FULL TXT FILE IN A LOOP, AND THE PROGRESS BAR IN THE SCREEN DOESN`T UPDATE.
// (IF I PUT THE PROGRAM IN STEP-BY-STEP, THE PROGRESS BAR UPDATES)

TR_SSALV(CLK:=SSALV); IF TR_SSALV.Q THEN MESCR:=TRUE; END_IF; // SET BIT OF STARTING OF FILE WRITING
TR2_NSSALV(CLK:=MESCR);
IF TR2_NSSALV.Q THEN udiCloseError1:= SysFileClose(hFile:= hFile); END_IF; //Close the file at the end

//DEFINE THE FILE NAME AND DIRECTORY
IF MESCR AND NOT Date_Time.xDone THEN
GVL.ESCO := FALSE;
Date_Time(xExecute:= TRUE);
DTU.DTSplit(dtDateAndTime:= Date_Time.dtDateAndTime, puiYear:=ADR(ANO), puiMonth:= ADR(MES), puiDay:= ADR(DIA), puiHour:= ADR(HORA), puiMinute:= ADR(MINUTO), puiSecond:= ADR(SEGUNDO));//PEGA DADOS DE DATA E HORA
STR_ANO := CONCAT(UINT_TO_STRING(ANO),''); STR_MES := CONCAT(UINT_TO_STRING(MES),''); STR_DIA := CONCAT(UINT_TO_STRING(DIA),''); STR_HORA := CONCAT(UINT_TO_STRING(HORA),''); STR_MINUTO := CONCAT(UINT_TO_STRING(MINUTO),'_');
sFileName := CONCAT(STR_ANO,STR_MES); sFileName := CONCAT(sFileName,STR_DIA); sFileName := CONCAT(sFileName,STR_HORA); sFileName := CONCAT(sFileName,STR_MINUTO); sFileName := CONCAT(sFileName,UINT_TO_STRING(SEGUNDO)); sFileName := CONCAT(sFileName,'.txt');
sFileName := CONCAT('C:\Laser\Gravados\', sFileName);
hFile:= SysFileOpen(szFile:= sFileName, am:= ACCESS_MODE.AM_WRITE_PLUS, pResult:= ADR(udiOpenError1));
MDATA := FALSE;
IF Date_Time.xError THEN
//erro
END_IF
END_IF

//STARTING STRING VARIABLE
TR_INIC(CLK := Date_Time.xDone);
IF TR_INIC.Q THEN xText_Write := ''; END_IF;

//MOUNTING THE PACKAGE STRING AND WRITING TO TXT
IF MESCR AND Date_Time.xDone THEN
FOR LOOP2 := 1 TO 3000 BY 1 DO
RPERC := 100.0 * (UINT_TO_REAL(LOOP2) / 3000.0); //PERCENT OF PROGRESS BAR
//IS THERE A WAY TO CALL HERE A SCREEN UPDATE BY PROGRAM LINE?????????????????????????????
StrConcatA(pstFrom:= ADR(txt_IP), pstTo:= ADR(xText_Write), iBufferSize:= 10000);
StrConcatA(pstFrom:= ADR(IP), pstTo:= ADR(xText_Write), iBufferSize:= 10000);
StrConcatA(pstFrom:= ADR(txt_Virg), pstTo:= ADR(xText_Write), iBufferSize:= 10000);
StrConcatA(pstFrom:= ADR(txt_Tempo), pstTo:= ADR(xText_Write), iBufferSize:= 10000);
TEMPO_STRING := UDINT_TO_STRING(TEMPO[LOOP2]);
StrConcatA(pstFrom:= ADR(TEMPO_STRING), pstTo:= ADR(xText_Write), iBufferSize:= 10000);
StrConcatA(pstFrom:= ADR(txt_Fim_Cab), pstTo:= ADR(xText_Write), iBufferSize:= 10000);
FOR LOOP:= 1 TO 5008 BY 1 DO
VAL_STRING2 := INT_TO_STRING(MSG_COM[LOOP2,LOOP]);
StrConcatA(pstFrom:= ADR(VAL_STRING2), pstTo:= ADR(xText_Write), iBufferSize:= 10000);
IF LOOP < 5008 THEN StrConcatA(pstFrom:= ADR(txt_Virg), pstTo:= ADR(xText_Write), iBufferSize:= 10000); END_IF;
TAM_STR := LEN(xText_Write);
IF TAM_STR >= 200 THEN
IF hFile <> RTS_INVALID_HANDLE THEN
udiWrite:= SysFileWrite(hFile:= hFile, pbyBuffer:= ADR(xText_Write), ulSize:= INT_TO_UDINT(LEN(xText_Write)), pResult:= ADR(udiWriteError1));
xText_Write := '';
END_IF
END_IF
END_FOR;
END_FOR;

MESCR := FALSE; GVL.ESCO := TRUE; SSALV:=FALSE;
Date_Time(xExecute:= FALSE);

END_IF

Hello sir,

could it be that in your project the visu_task has a lower priority than the task you use to write to the file?

Best regards,
Marcel

Yes. This is true. But in fact I would like my program with priority over screen. I understood that with 1 ms of ciclic interval, my program takes all processment and the screen doesn`t update even when the program is not in a loop. Then, my question is:
Is there a way to call a screen update by program?

Thank you by your reply!

Hello sir,

no there is no public way to force a screen update.
Even if there would be a way, if the VISU_TASK gets no CPU-time, it cannot paint.

Best regards,
Marcel

Do you need to use FOR loops? I would highly consider changing it to a CASE statement so that your program can continue to cycle properly. A good example can be found in the help: https://help.codesys.com/webapp/Examples;product=CAA_FILE;version=3.5.13.0

A FOR loop might be the fastest way to save the file but as you've noticed it drastically increases cycle time for that 1 cycle you are saving a file. This means that other lower priority tasks get put on hold. You can get creative with creating a separate task for saving the files that will help speed up the saving process if you don't want to lock up the system.

Even when not in a loop, I have the same problem unless I rise up the interval of ciclic time to over 20ms. But this is not desired....
However, my final project would be with the multi-core codesys. Then, I think this wouldn't be a problem to me, once I can put the TXT file program in a separate core. I will wait to buy it and then I will reanalize this issue.
Thanks!!