Implementation-dependent parameters
IEC compliance table for implementation-dependent parameters:
Parameters |
Limitations/Behavior |
---|---|
Maximum length of identifiers |
32 characters |
Maximum comment length |
Within the Control Expert: 1024 characters for each editor object. Import: limited by XML constraints or UDBString usage in the persistent layer. |
Syntax and semantics of pragmas |
Unity Pro V1.0 only implements 1 pragma, used for legacy convertor:
any other pragma construct is ignored (a warning message is given) NOTE:
Unity Pro is the former name of Control Expert for version 13.1 or earlier. |
Syntax and semantics for the use of the double-quote character when a particular implementation supports Feature #4 but not Feature #2 of Table 5. |
(#2 of table 5 is supported) |
Range of values and precision of
representation for variables of type |
for (=t for for |
Precision of representation of
seconds in types |
|
Maximum number of enumerated values |
Not applicable |
Maximum number of array subscripts |
6 |
Maximum array size |
64 kbytes |
Maximum number of structure elements |
no limit |
Maximum structure size |
no limit |
Maximum range of subscript values |
|
Maximum number of levels of nested structures |
10 |
Default maximum length of |
16 characters |
Maximum allowed length of |
64 kbytes |
Maximum number of hierarchical levels Logical or physical mapping |
Premium: physical mapping (5 levels) Quantum: logical mapping (1 level) |
Maximum number of inputs of extensible functions |
The number of all input parameters (including in-out parameters) is limited to 32. The number of all output parameters (including in-out parameters) is also limited to 32. Thus the limit for extensible input parameters is (32 - number of input parameters - number of in-out parameters). The limit for extensible output parameters is (32 - number of output parameters - number of in-out parameters). |
Effects of type conversions on accuracy |
See online help. |
Error conditions during type conversions |
Error conditions are described
in the online-help. Globally |
Accuracy of numerical functions |
INTEL floating point processing or emulation. |
Effects of type conversions between time data types and other data types not defined in Table 30 |
See online help. |
Maximum number of function block specifications and instantiations |
Only limited by the maximum size of a section. |
Function block input variable assignment
when |
No assignment |
|
|
Effect of a change in the value
of a |
The new |
Program size limitations |
Depends on controller type and memory |
Precision of step elapsed time |
10 ms |
Maximum number of steps per SFC |
1024 steps per SFC section |
Maximum number of transitions per SFC and per step |
Limited by the available area for entering steps/transitions and by the maximum number of steps per SFC section (1024 Steps). 32 transition per step. Limited by the available area for entering Alternative/Parallel branches, maximum is 32 rows. |
Maximum number of action blocks per step |
20 |
Access to the functional equivalent
of the |
not applicable |
Transition clearing time |
Target dependent; always < 100 micro-seconds |
Maximum width of diverge/converge constructs |
32 |
Contents of |
Not applicable |
Effect of using |
Not applicable |
Maximum number of tasks |
Depends on controller type. Maximum on most powerful controller: 9 tasks |
Task interval resolution |
10 ms |
Maximum length of expressions |
Practically no limit |
Maximum length of statements |
Practically no limit |
Maximum number of |
Practically no limit |
Value of control variable upon
termination of |
Undefined |
Restrictions on network topology |
No restrictions |
Evaluation order of feedback loops |
The block connected to the feedback variable is executed first |