Lenze PLC Designer ApplicationTemplate (PLC Designer R3-x) - Manual (Page 99)

Lenze · ApplicationTemplate · 1.3 EN - 04/2013
99
Architecture: The ApplicationTemplate in detail
Consistent data transfer
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9.16 Consistent data transfer
A defined data area is exchanged between two tasks so that it is transferred consistently to the
other task.
Data consistency...
• ...is ensured depending on the data, or
• ...to be ensured for specific application cases. Depending on the application case, proceed as
follows:
In order to be able to use the multitasking
functionality in a machine module, the
machine module must be provided with more
than one module application.
Application case Data element/data type Description
Data consistency within individual
data elements
Integer
INT
DINT
Direct access is permissible.
Bit fields
WORD
DWORD
Data consistency within one data
element
Floating point
LREAL
When the controller is used, data
consistency of an LREAL variable is
ensured.
Data consistency for more than one
data element
The data areas have to be...
• ...inhibited for others tasks before
the first access, using the Lock()
method.
• ...re-enabled after the last access,
using the Unlock() method.