Siemens SIMATIC S5 Manual page 133

Programming the IP 265 with COM 265
Quantity framework restrictions for COM 265
The COM 265 quantity framework restrictions relating to editing of the IP 265 user program are less
"limiting" than those for the IP 265, i.e. COM 265 allows you to edit and test a more complex IP 265
user program than the IP 265 can actually accommodate.
COM 265 must be able to make this possible in order to enable
• off-line testing of two upgraded IP 265s
• additional program structures required exclusively for program testing, i.e. structures which are
not to be compiled and loaded into the IP 265.
COM 265 is subject to the following editing restrictions:
Note
• An IP 265 user program may comprise no more than 32 segments.
• A maximum of 31 COM 265 language elements may be interconnected per segment.
• A segment may contain no more than one language element with more than one
output (applies to counters). There may be no objects at the right of this language
element (remedy: connector).
• In a segment, the outputs of only one language element (outer right) can be run to
the output bar.
• Identifiers for operands (direct or symbolic addresses) may comprise no more than
24 characters. However, only the first 15 characters are shown in the operand
fields of the control system flowchart's margin bars.
Tips for optimum utilization of the IP 265
Always try to solve complex tasks using as little IP 265 program capacity as possible.
Note
• Select practical direct addresses for binary parameters; combine several bit
parameters into a byte.
• Initialize timers, counters and comparison functions with constants wherever
possible.
Avoid initializing these language elements via parameters.
• If you want to debounce fewer than five 24 V inputs, program in the following
address groups:
- (I 0.y where y=0, 1, 3, 7) or
- (I 0.y where y=2, 4, 5, 6)
9-28
IP 265
EWA 4NEB 812 6130-02a