9300 Servo PLC
Preface and general information
1-3
9300ServoPLC EN 1.4
1.2 Lenze software guidelines for variable names
The previous concepts for Lenze drive controllers were based on codes that represented the input
and output signals, and the parameters of function blocks.
• For the sake of clarity, names were defined for the codes in the documentation.
• In addition, the signal types were defined by graphical symbols.
The user could see at a glance which kind of signal (analog, phase-angle etc.) had to be present at
the particular interface.
The concept for the new automation system does not use direct codes in the
programming. The IEC1131-3 standard is used instead.
• This standard is based on a structure of variable names.
• If the user applies variables in his project, then he can name the variables as he chooses.
In order to avoid the growth of a multitude of different conventions for naming variables in existing
and future projects and function libraries that are programmed by Lenze personnel, we have set up
software guidelines that must be followed by all Lenze staff.
In this convention for creating variable names, Lenze keeps to theHungarian Notation, that has been
specifically expanded by Lenze.
If you make use of Lenze-specific functions or function blocks, you will immediately be able to see,
for instance, which data type you must transfer to a function block, and which type of data you will
receive as an output value.
1.2.1 Hungarian Notation
These conventions are used so that the most significant characteristics of a program variable can
instantly be recognized from its name.
Variable names
consist of
• a prefix (optional)
• a data-type entry
• and an identifier
The prefix and data-type entry are usually formed by one or two characters. The identifier (the
“proper” name)should indicate the application, and is therefore usually somewhat longer.
Prefix examples
Prefix Meaning
a array (combined type), field
p pointer
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