Definition of Variables

Use

You define variables if you want to transfer the value of a message characteristic to another process instruction.

You can define variables in the following cases, for example:

Variables in entries to refer to the values to be entered
See also: Type 0: Definition of Entries
Variables in calculations to refer to the values to be calculated
See also: Type 0: Definition of Calculations
Variables that refer to characteristics whose values are assigned automatically
See also: Type 0: Definition of Automatic Value Assignment
Variables in dynamic function calls to refer to the import parameters that are transferred to the PI sheet;
See also: Type 0: Definition of Import Parameters
Variables in dynamic function calls to refer to the table parameters that are transferred to the PI sheet;
See also: Type 0: Definition of Table Parameters

You can define a variable for every message characteristic of a process instruction. The data type of the variable is identical to that of the message characteristic (for example, CHAR or NUM).

The following types of variables are distinguished:

Simple variables

Can only be used in the same PI sheet or cockpit in which they were defined
You use characteristic PPPI_VARIABLE.
Global variables
can be exchanged as follows:
- Between different PI sheets of the same process order
- As data points using the internal interface Manufacturing Data Access:
  - Between PI sheets of different process orders
  - Between PI sheets and cockpits (in the same frameset)
  - Between different cockpits (in the same frameset)
    
    You use characteristic PPPI_GLOBAL_VARIABLE.
    
    For more information on Manufacturing Data Access , see:
- Manufacturing Data Access
- Manufacturing Data Points
- Type 0: Definition of Manufacturing Data Access

Activity

Simple Variables

You define a simple variable by assigning the following characteristic to the process instruction immediately before the message characteristic whose value you want to transfer to the variable:

Characteristic	Meaning	Value
PPPI_VARIABLE	Simple variable that can only be used within one PI sheet or cockpit	New variable name

Example Example

Example of simple variables

The simple variable VAR is defined for the input value “material quantity”. The value of variable VAR is to be displayed somewhere else in the PI sheet.

Process instruction 0010:

End of the example.

	PPPI_INPUT_REQUEST	Material quantity
	PPPI_VARIABLE	VAR
	PPPI_REQUESTED_VALUE	PPPI_MATERIAL_QUANTITY

Process instruction 0020:

	PPPI_OUTPUT_TEXT	Material quantity
	PPPI_OUTPUT_VARIABLE	VAR

Global Variables

You define a global variable by assigning the following characteristic to the process instruction immediately before the message characteristic whose value you want to transfer to the variable:

Characteristic	Meaning	Value
PPPI_GLOBAL_VARIABLE	Global variable that can be exchanged between different PI sheets and cockpits	New variable name

Example Example

Example of global variables

A totals calculation is to be executed in cockpit PMC1. The global variable VARSUM was defined for the value calculated.

The value of variable VARSUM is to be read in cockpit PMC2 as a data point using Manufacturing Data Access and transferred to the simple variable VARLC. The value calculated is to be displayed in cockpit PMC2.

End of the example.

Caution Caution

This functionality is available for two cockpits or for one cockpit with a PI sheet in the same frameset only.

Cockpit PMC1:

End of the caution.

	PPPI_INPUT_REQUEST	Calculate value
	PPPI_GLOBAL_VARIABLE	VARSUM
	PPPI_CALCULATED_VALUE	PPPI_MATERIAL_CONSUMED
	PPPI_CALCULATION_FORMULA	VAR1 + VAR2

Cockpit PMC2:

	PPPI_DATA_ACCESS	Manufacturing Data Access
	PPPI_BUTTON_TEXT	Read value from PCM1
	PPPI_FUNCTION_DURING_DISPLAY	Permitted
	PPPI_IMPORT_DATA	PMC:0001.PMC1.VARSUM
	PPPI_STRING_VARIABLE	VARLC
	PPPI_OUTPUT_TEXT	Value calculated
	PPPI_OUTPUT_VARIABLE	VARLC

Note the following:

In general, you can choose any name for a variable. To avoid conflicts with other functions, do not use:

Variable name X
Variable names that start with SY_ since these are system variables predefined by SAP
Blanks and arithmetic operators as part of the variable name
The following character strings at the end of the variable name:

_< number >, for example, _1, _2

_ COUNT

_ SUM

For more information, see Using Variables in Browser-Based PI Sheets and Cockpits .