efka

The critical thing in your actual solution is, that the script acts on a change of the tag in your switch. I guess, that this tag changes very often. Am I right?

efka

You shouldn't do this, because I in my eyes this is very time critical and cause errors, when the system hangs one time for a second.

A bit of follow up.

efka

Maybe it is a little more neat solution, when you use cyclic scripts with a trigger cycle of five or maybe also two seconds.

#include "apdefap.h"

int gscAction( void )
{
// Define the 2 arrays we are going to loop
char *arsw[10] = {"010","020","030","040","050","060","070","080","090","100"};
char *arpr[10] = {"01","02","03","04","05","06","07","08","09","10"};
// define the local variables that we will use
char tekst[40];
//loop vars
char *switchnaam;
char *poort;
int loop1=0;
int loop2=0;
// temp
int currVal, prevVal, octetDiff;
double mul, loadBits;

for (loop1=0; loop1 < 10; loop1++)
{
switchnaam = arsw[loop1];
for (loop2=0; loop2 < 10; loop2++)
{
poort = arpr[loop2] ;
// START OF CALCULATIONS - START OF CALCULATIONS - START OF CALCULATIONS
// 1. PORT LOAD CALCULATION IN
// get currVal
sprintf(tekst,"PNIO_%s_ifInOctets_Port_%s", switchnaam, poort);
currVal = GetTagDWord(tekst);
// get prevVal
sprintf(tekst,"PNIO_%s_prev_ifInOctets_Port_%s", switchnaam, poort);
prevVal = GetTagDWord(tekst);
// set the prevVal TAG (we do this here, because we already have the correct tekst
SetTagDWord(tekst,currVal);
// calculate LOAD
octetDiff = currVal - prevVal; //( value in Bytes)
mul = 0.0016;
loadBits = octetDiff * mul;
// set the LOAD IN TAG
sprintf(tekst,"PNIO_%s_Load_in_Port_%s", switchnaam, poort);
SetTagDWord(tekst,loadBits);
// 2. PORT LOAD CALCULATION OUT
// get currVal
sprintf(tekst,"PNIO_%s_ifOutOctets_Port_%s", switchnaam, poort);
currVal = GetTagDWord(tekst);
// get prevVal
sprintf(tekst,"PNIO_%s_prev_ifOutOctets_Port_%s", switchnaam, poort);
prevVal = GetTagDWord(tekst);
// set the prevVal TAG (we do this here, because we already have the correct tekst
SetTagDWord(tekst,currVal);
// calculate LOAD
octetDiff = currVal - prevVal; //( value in Bytes)
mul = 0.0016;
loadBits = octetDiff * mul;
// set the LOAD IN TAG
sprintf(tekst,"PNIO_%s_Load_out_Port_%s", switchnaam, poort);
SetTagDWord(tekst,loadBits);
// END OF CALCULATIONS - END OF CALCULATIONS - END OF CALCULATIONS

}// end the ports for loop
} // end the switches for loop
return 0;
}

[/code]

I'm a beginner in C programming, so someEfficiency and Stability improvements for this script are very welcome.

e.g. I use sprintf to concatenate the names of the tags. Is this good practice?

I modified my original script in an attempt to improve the stability.

I created a project funtion
[code]void CalcLoad(char* bytesTag, char* prevBytesTag, char* loadTag, int divr)
{
int currVal, prevVal, octetDiff, loadBits;
currVal = GetTagDWord(bytesTag);
prevVal= GetTagDword(prevBytesTag);
setTagDWord(prevBytesTag, currVal);

octedDiff = currVal - prevVal;
loadBits = octetDiff/divr;

SetTagDWord(loadTag,loadBits);
}[/code]

And i a global action I just call this function 200 times with different tagnames.

Unfortunately WinCC needs alot of time when activating. The first 5-10 minutes screen changes are impossible. After those first minutes everything works ok.

This topic (from 2008)talks about something similar and also suggests a few workarounds.
https://www.automation.siemens.com/tf/WW/en/Posts/18158

RonaldNijssen

The trick is to make something notify the Data Manager that these tags should be available and being read "before" your script runs. This can be accomplished in various ways:
1. declare them in the script and use them as a trigger
2. Put them by means of a "direct connection" in a graphic that is present before the script runs
3. Use them in tag or alarm logging