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What is the best way for me to learn about variables? I have no programming experience and when I read the threads about variables I get very confused.

Thanks!

variables are just numbers that are assigned names. [EDIT: It would have been better to say "variables are names that are assigned numbers" ] The numbers can change. . .thus they are "variable". There are 2 types in ISY.

Integer: These variables will not trigger a program.
State: These will trigger a program.

In other words, if the value of a variable changes, a state variable will cause a program to run if there is a reference to it in the "if" clause. An integer variable will not cause the program to run, but it will be checked if something else triggers it to run.

Example:
If state variable y = 1
and the time is 1pm
Then do this
Else do that

The above program will run every time y changes. So if some other program changes y at any time of day or night, the program runs and either "else" or "then" executes depending on if it is true or false. It will also run at 1pm and depending on if y is 1 or something else, either "then" or "else" executes.

If integer variable y = 2
and time is 1pm
The do this
Else do that

The above program will run at 1pm. . . and that is it. If at 1 pm the program runs and y happens to be 2, then the "then" clause executes. Otherwise, the "else" does. Besides 1pm, this program could be forced to run by a manual "run" command or another program that contains a "run" command which points to this program. But on it's own, it only runs at 1pm.

That is a great explanation!

Now let me ask about this program...



I know what $Home.Sick is 0 does/is but

-What does $Home.Sick Init To 0 do?

-What does $Home.Sick Init To $Home.Sick do?

Thanks!

Nice explanation..


Thanks!

Brian

Init is the initializing value of the variable. When ISY reboots, the value is set to the init value. So if you want it to hold steady through a power failure or reboot of any kind, you need to set the init value coincident with the working value.