Global Variable Writing

## Global Variable Writing

![](/media/202601/087ee859-1e09-4f88-8188-efb93a91a72d_1768993782.png)

## Module Principle
When subscribing, the data of the output port associated with the input port of the module is set to the corresponding global variable; when not subscribing, the value of the input port of the module is set to the corresponding global variable. At the same time, set the global variable to valid.

## Usage Scenarios
Used to modify the value of a global variable while setting the global variable to valid.

## Usage Method
1. Function Addition Tree &rArr; Auxiliary Tools &rArr; Variable Processing &rArr; Global Variable Writing Module, drag or double-click to add to the specified position in the flow.
2. Add the global variable to be modified.
3. If ==Subscribe== is checked, click ==Data Source== to select the data to be modified; if ==Subscribe== is not checked, double-click ==Modify Value== to set the value to be set.

## Parameter Configuration Description
![](/media/202601/ea7e1f92-08b7-4f97-8ac8-d27cfadc3afa_1768993820.png)
Global Variable in Table: Click to pop up the global variable menu, select the global variable to be written.
Data Type in Table: Display the data type of the global variable.
Subscribe in Table: If checked, the modification value is the output port connected to the data source; if not checked, the modification value is the value of the input port.
Data Source in Table: Click to pop up the output port corresponding to the global variable data type, select the output port to be set.
Modify Value in Table: When ==Subscribe== is checked, the value of the data source is displayed; when ==Subscribe== is not checked, double-click to modify the value to be set.
Table operations include the following:
1. Plus sign: Click to add a group of read global variables and corresponding input ports.
2. Minus sign: Click to delete the selected group of read global variables and corresponding input ports.
3. Clear: Click to clear all read global variables and corresponding input ports.

## Output Description
![](/media/202601/8c3375f4-1871-436f-b094-dcf7029c18a1_1768993828.png)
1. Run Result: Whether the global variable was modified successfully.

## Precautions
1. Be sure to set the global variable to be written first, then select the output port or set the value.

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Click here to jump to the corresponding Chinese manual page: [Global Variable Writing
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