Siemens Portal (TIA Portal) Will you use variable-length arrays?

Preamble

Do you encounter the following problems every time, for example, create FB/FC function blocks of different lengths to set different lengths for array operations of different lengths, so as to ensure that the input array is consistent with the pin parameters of the function block, and the size and length of the array are the same. By changing the length of the array, the workload can be greatly reduced.

1. Comparison between mutable arrays and immutable arrays

1. Traditional array_function block variables

The input/output variables of the function block must be the same as the DB block variables.

Function block 1 variables:

Function block 2 variables:

DB block variables:

For traditional immutable array operations and arrays of different lengths, independent FB/FC function blocks must be created.

2. Variable-length array_ function block variable

The input/output variables of the function block do not need to be the same as those of the DB data block, and the length of the DB data block can be specified

Function block 1/2 variables:

DB block variables:

Variable array operation, arrays of different lengths, no need to create a new independent FB/FC function block.

2. Explanation of variable arrays

1. Create a new FC block

2. The FC function block inserts the following variables

3.FC function block inserts the following programs

//获取数组下限
#数组下限 := LOWER_BOUND(ARR := #输入数组, DIM := 1);
//获取数组上限
#数组上限 := UPPER_BOUND(ARR := #输入数组, DIM := 1);
//赋值前清零
#输出和_Temp := 0;
//数组求和
FOR #Temp_1 := #数组下限 TO #数组上限 BY 1 DO
    // Statement section FOR
    #输出和_Temp += #输入数组[#Temp_1];
END_FOR;
//数组求和值中转
#输出和 := #输出和_Temp;           

4. Create a new DB block

Insert the following variables 5.DB the data block

6. Insert the variable array FC function block twice into the OB1 function block

3. Program demonstration

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