System INPUT signal

Robot Controller
1

I am using system input signal " startmain" to start the main program from PLC. When we start main from PLC would it erase all my variables to their default value or their values will be retained?

2

Dear Natalia

By my experience, “StartAtMain” would not erase/reset the variables as long as we don’t declare something which can reset them on the “main” procedure.
For example:

PROC main()
VAR num Stack:=0;
…
Stack:=0;
…
MoveL…

But be careful for using VAR type, because some variables can be erased to their default value after controller is shutdown.

BR

3

Hey, Thanks Dhyan. I am using it to start Home move from PLC, I will let you know how it works.

4

The part of my code is like this,
var num count =0; ! defined in user.sys

proc main()
LOOP:
…
…
myproc1;
Goto LOOP;
endproc

proc myproc1()
count=count+1;
endproc

When the program is stopped from the PLC and started again from main (StartMain) by the PLC, I still need the count variable to remember its value it has when the program was stopped.

5

Hi Natalia,

You need to define count variable as persistent.

PERS num count:=0;

BR.

6

Yea thank you very much , I did that and wanted to confirm it. Thank you very much