Siemens CPU 948, Programming Manual

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Stage 3 Creating, testing and starting up the program:
Stage Activity
1 Decide on the type of representation for the logic
blocks (LAD, CSF or STL, refer to Chapter 2).
Remember that function blocks can only be created in
the STL method of representation.
2 Program all logic and data blocks (please refer to your
STEP 5 manual).
3 Start up the blocks one after the other (you may have
to program a different OB for each individual step, to
call the logic blocks):
1a: load the block(s)
1b: test the block(s)
(For more detailed information please refer to your
STEP 5 manual and Chapter 11).
4 When you are certain that all the logic blocks run
correctly and all the data can be correctly calculated
and stored, you can start up your whole program.
Note on test strategies
When you actually start up your program for the first time in genuine
process operation, i.e. with real input and more importantly output
signals, is a decision that must be left up to yourself or to a team of
experts.
The more complex the process, the greater the risk and therefore the
greater the care required when starting up.
How to Tackle Programming
CPU 948 Programming Guide
C79000-G8576-C848-04
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