TIA portal - choosing array number based on INT

[rQx]

Hi!

I'm working on a program with several arrays. I have one integer that I want to use to choose witch array will get assigned a value. For example:

I have a Dint value of 1234

I have a Int (my choosing tag) with the value of 5

I have a Array[1..10] of Dint

Now I want to move the Dint value to the Array number 5. Is there a easy way of doing this so that I don't have to use one comparator for each situation? I have several of these arrays and I don't want to make any unnecessary (no idea how to spell that) work.

/Tim

 

[lostcontrol]

You didn't say where in the array '5' you want to move the DINT to..
But I that is a mute point for now, sounds like you need a 2-dimensional array.

 

[rQx]

I want to use a move instructions to move the value of my Dint. To the fifth array (array[5]) without using alot of compare and stuff.

 

[WJhsson]

Hi,
Just to clearify what you want to achieve,
do you mean that you have only one array with 10 elements or do we speak of multiple array's?

Are you working in STL or SCL?

If it's STL, the easiest way would be to use indirect adressing.


Assuming STL, one array and that your array is declared locally it could look something like this:


L P##"name of your array variable"
LAR1
L "INT pointing to element"
SLD 5
+AR1
L "DINT with value to store in array"
T D[AR1, P#0.0]



/ W



EDIT: Oooops! missed that you are working in TIA. Above mentioned regards Step 7 Classic

 

[rQx]

I'm using ladder and I have

>Array Array[1..10] of Dint

This is a Array that consist of 10 Dint values.

I have an Integer witch we can name: "Choose Int"
I have an DInteger with a value I want to assign to diffrent positions in my array.

If my "Choose Int" is set to 5, I want to move the Dinteger to the fifth element in my array.

>Array Array[1..10] of Dint
array[1]
array[2]
array[3]
array[4]
array[5] <----- this element

I know I can use a compare instruction for each element of the array to move the Dinteger to the correct position. What I wan't to know is if there is any other, better (smaller) way to do it. Since this is a scenario that will occur often in my program.

 

[Sioan]

L    L#5 ; //or     L    #ChooseInt ;
T    [B][COLOR="blue"]#arr[/COLOR][/B][5] ;

?

You should not use the name "array[x]" ( it is used from system )


arr is the array !
arr[5] is the element 5 of the array arr

 

[Sioan]

In practical use , use an adequate kind of symbol for example:
valve[5],
motor[5],
conveyor[5]

 

[Mike_RH]

You don't mention which CPU family you are using.
Is it a S7-1200 or a S7-300/400.
This makes a difference as the 1200 does not have STL capability.

 

[JRW]

What CPU?

 

[Sioan]

I think you can also use array indexes dynamically in TIA !

(I do not have TIA!)

 

[DamianInRochester]

L    L#5 ; //or     L    #ChooseInt ;
T    [B][COLOR="blue"]#arr[/COLOR][/B][5] ;

?

You should not use the name "array[x]" ( it is used from system )


arr is the array !
arr[5] is the element 5 of the array arr

He likely did in this case so that it was obvious to those in the forum that it is an array. If I am positing an example of an array I usally name it "SomeArray" or similar to make that point clear.

 

[Sioan]

Mea culpa !
If I was wrong !

 

[rQx]

s7-1200 is the CPU.

Thanks for all the effort into helping me.

I just stumbled upon the block "field_write" this is exactly what I need.

You have a "somearray[1]" output
A index tag witch will choose witch component of the "somearray[1]" input to write to
And you have a Value input with the vale to write. This is exactly what I needed!

Thanks for all the help, I'll be sure to tell the CPU next time I post a thread. I've never used other CPU then s7-1200 with TIA portal so TIA portal is s7-1200 for me

 

[Venkata Suresh]

I'm using ladder and I have

>Array Array[1..10] of Dint

This is a Array that consist of 10 Dint values.

I have an Integer witch we can name: "Choose Int"
I have an DInteger with a value I want to assign to diffrent positions in my array.

If my "Choose Int" is set to 5, I want to move the Dinteger to the fifth element in my array.

>Array Array[1..10] of Dint
array[1]
array[2]
array[3]
array[4]
array[5] <----- this element

I know I can use a compare instruction for each element of the array to move the Dinteger to the correct position. What I wan't to know is if there is any other, better (smaller) way to do it. Since this is a scenario that will occur often in my program.

Indirect addressing is possible,in this case
Move Dinteger to Array["choose_Int"]

 

[Mike_RH]

RQx,

The Field read and write instructions are the best choice for what you wish to do.