You can use the internal interface Manufacturing Data Access to carry out the following from within the PI sheet or manufacturing cockpit:
Read manufacturing data points from another application
Write manufacturing data points to another application
Subscribe to manufacturing events from another application
These events are then automatically reported to the PI sheet or cockpit when they occur. In this way, you can, for example, subscribe to value changes.
In addition, events can contain parameters that you can read while processing an event.
All applications that are registered at the interface as a service can provide data points and events and receive them from other services. In this way, values from one or more data points can be:
Read or written synchronously,
this means on request (for example, by pressing a button)
Read or written on an event-driven basis,
this means that in running applications, data is automatically read or written – triggered by an event – without any user interaction
Events can also be processed in different system logons running in parallel.
Example:User A maintains PI sheet 001. User B maintains PI sheet 002. Value changes in PI sheet 002 can be transferred automatically to PI sheet 001 although the two users are logged on at different terminals.
For more information, see Manufacturing Data Access .
OPC Items and OPC Events
To use items (data points) of the services ODA (OPC Data Access) and OAE (OPC Alarms/Events), you must first have created a subscription in Customizing.
To do so, go to Customizing for Process Management and choose SAP ODA (OPC Data Access) .
For more information about SAP ODA, see SAP OPC Data Access .
When defining Manufacturing Data Access, you define the characteristics below in a process instruction of Type 0: Universal process instruction category in the sequence specified. You can read (PPPI_IMPORT_DATA) and write (PPPI_EXPORT_DATA) any number of data points in a Manufacturing Data Access definition. However, there may be no other characteristics within the Manufacturing Data Access definition.
You must assign an address to PPPI_IMPORT_DATA and PPPI_EXPORT_DATA that contains the name of a global variable or data point.
For more information on the structure of data point addresses, see Manufacturing Data Points .
You must assign an address to PPPI_EVENT that contains the name of the event to which the PI sheet or cockpit wants to subscribe.
For more information on the structure of event addresses, see Manufacturing Events .
Read Data Point
Characteristic |
Meaning |
Value |
PPPI_DATA_ACCESS |
Manufacturing Data Access |
Manufacturing Data Access |
PPPI_BUTTON_TEXT |
Text of the pushbutton (optional) |
Any short text |
PPPI_FUNCTION_DURING_DISPLAY |
Setting to specify whether the function is permitted in display mode (optional) |
< Permitted < Not permitted |
PPPI_IMPORT_DATA |
Data point or global variable of the application from which the value is to be transferred to the subsequent variable |
Address with the name of the global variable or data point |
One of the following characteristics: < PPPI_STRING_VARIABLE < PPPI_FLOAT_VARIABLE < PPPI_DATE_VARIABLE < PPPI_TIME_VARIABLE |
Value transfer in variable: < Alphanumeric value < Floating point number < Date < Time |
Variable of data type: < Alphanumeric value < Floating point number < Date < Time |
Example
Example for "Read Data Point"
You want to read the current value of data point MYODA in plant 0001 of service ODA and transfer it to the local variable MYVAR.
PPPI_DATA_ACCESS |
Manufacturing Data Access |
|
PPPI_BUTTON_TEXT |
Read data point |
|
PPPI_FUNCTION_DURING_DISPLAY |
Permitted |
|
PPPI_IMPORT_DATA |
ODA:0001.MYODA.PV |
|
PPPI_STRING_VARIABLE |
MYVAR |
Write Data Point
Characteristic |
Meaning |
Value |
PPPI_DATA_ACCESS |
Manufacturing Data Access |
Manufacturing Data Access |
PPPI_BUTTON_TEXT |
Text of the pushbutton (optional) |
Any short text |
PPPI_FUNCTION_DURING_DISPLAY |
Setting to specify whether the function is permitted in display mode (optional) |
< Permitted < Not permitted |
PPPI_EXPORT_DATA |
Data point or global variable of the application into which the value of the subsequent variable is to be transferred |
Address with the name of the global variable or data point |
One of the following characteristics: < PPPI_STRING_VARIABLE < PPPI_FLOAT_VARIABLE < PPPI_DATE_VARIABLE < PPPI_TIME_VARIABLE |
Value transfer in variable: < Alphanumeric value < Floating point number < Date < Time |
Variable of data type: < Alphanumeric value < Floating point number < Date < Time |
Example
Example for "Write Data Point"
You want to write the value of the local variable MYVAR to the global variable GINVAR and export it as a data point to service PMC. There, the value of GINVAR is to be written to cockpit MYCOCKPIT in plant 1100.
PPPI_DATA_ACCESS |
Manufacturing Data Access |
|
PPPI_BUTTON_TEXT |
Write data point |
|
PPPI_FUNCTION_DURING_DISPLAY |
Permitted |
|
PPPI_EXPORT_DATA |
PMC:1100.MYCOCKPIT.GINVAR |
|
PPPI_STRING_VARIABLE |
MYVAR |
Read Value of Data Point on Event-Driven Basis
Characteristic |
Meaning |
Value |
PPPI_DATA_ACCESS |
Manufacturing Data Access |
Manufacturing Data Access |
PPPI_BUTTON_TEXT |
Text of the pushbutton (optional) |
Any short text |
PPPI_FUNCTION_DURING_DISPLAY |
Setting to specify whether the function is permitted in display mode (optional) |
< Permitted < Not permitted |
PPPI_EVENT |
Internal or external event |
Address with name of the event |
PPPI_IMPORT_DATA |
Data point or global variable of the application from which the value is to be transferred to the subsequent variable |
Address with the name of the global variable or data point |
One of the following characteristics: < PPPI_STRING_VARIABLE < PPPI_FLOAT_VARIABLE < PPPI_DATE_VARIABLE < PPPI_TIME_VARIABLE |
Value transfer in variable: < Alphanumeric value < Floating point number < Date < Time |
Variable of data type: < Alphanumeric value < Floating point number < Date < Time |
Example
Example for "Read Value of Data Point on Event-Driven Basis"
The value change of data point MYODA in plant 0001 of service ODA is defined as an event. When the value of this data point changes, it is to be read and written to the local variable MYVAR.
PPPI_DATA_ACCESS |
Manufacturing Data Access |
|
PPPI_BUTTON_TEXT |
Read data point |
|
PPPI_FUNCTION_DURING_DISPLAY |
Permitted |
|
PPPI_EVENT |
ODA:0001.MYODA.VCHD |
|
PPPI_IMPORT_DATA |
ODA:0001.MYODA.PV |
|
PPPI_STRING_VARIABLE |
MYVAR |
Write Value of Data Point on Event-Driven Basis
Characteristic |
Meaning |
Value |
PPPI_DATA_ACCESS |
Manufacturing Data Access |
Manufacturing Data Access |
PPPI_BUTTON_TEXT |
Text of the pushbutton (optional) |
Any short text |
PPPI_FUNCTION_DURING_DISPLAY |
Setting to specify whether the function is permitted in display mode (optional) |
< Permitted < Not permitted |
PPPI_EVENT |
Internal or external event |
Address with name of the event |
PPPI_EXPORT_DATA |
Data point or global variable of the application into which the value of the subsequent variable is to be transferred |
Address with the name of the global variable or data point |
One of the following characteristics: < PPPI_STRING_VARIABLE < PPPI_FLOAT_VARIABLE < PPPI_DATE_VARIABLE < PPPI_TIME_VARIABLE |
Value transfer in variable: < Alphanumeric value < Floating point number < Date < Time |
Variable of data type: < Alphanumeric value < Floating point number < Date < Time |
Example
Example for "Write Value of Data Point on Event-Driven Basis"
The value change of the local variable MYVAR is defined as an event. When the value of this variable changes, you want to write it to the global variable GINVAR and export it as a data point to service PMC. There, the value of GINVAR is to be written to cockpit MYCOCKPIT in plant 1100.
PPPI_DATA_ACCESS |
Manufacturing Data Access |
|
PPPI_BUTTON_TEXT |
Write data point |
|
PPPI_FUNCTION_DURING_DISPLAY |
Permitted |
|
PPPI_EVENT |
Parameter changed |
|
PPPI_EXPORT_DATA |
PMC:0001.MYCOCKPIT.GINVAR |
|
PPPI_STRING_VARIABLE |
MYVAR |