Omron CX-Supervisor, Руководство пользователя

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Drawing SECTION 20 Best Practices
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CX-Supervisor only allows update rates in standard groups, which allows
a greater chance for CX-Server to optimise reads together. Old projects
may still be using non-standard update rate and are best changed to the
standard rates.
• Use few update rates
Even when using the standard update rates, use as few different update
rates as possible, ideally 5 or less different rates. Try to use the same
update rates for the same areas of PLC memory so optimisations can
occur.
• Use sensible update rates
Aim to keep update rates low. 5 seconds or 1 second updates should
suffice. If faster than 1 second updates are needed always question
"Why?". If fast update rates are required pay special attention to consider
if they can be disabled when not required.
• Use Copy/Paste to Excel for bulk editing
During development, the point editor supports Copying and Pasting in
textual format so Excel's powerful editing / formulas can be used to create
definitions for points. This can allow thousands of consecutive points to be
created in seconds.
• Use <Shift> and <Ctrl> to select multiple points for editing
During development, using <Shift> and <Ctrl> while selecting can be
useful to apply the same changes to many points.
• Use Hungarian notation
Improve readability and maintenance by defining and using a standard
naming convention. For example Hungarian notation where variable
names are prefixed by a type character e.g. bMyBooleanPoint,
nMyIntegerNumber, txtMyTextPoint or rMyReal.
• Use default optimisations
Leave the default communications optimisations turned on. In nearly all
cases they really do provide the best solution. Seek advice if you are
considering turning them off.
• Delete unused points
After a development phase and prior to deployment, delete any unused
points. These are listed in the Point Editor under the group "<Unused
Points>".
20-4 Drawing
This section covers some good practices when drawing the screens. These
can greatly speed up application development and help produce a
professional looking system.
• Start new pages with ‘Snap to Grid’
During the creative phase of any page this helps ensure objects are
automatically aligned and sized, saving time tidying up later.
• Use cursor keys for fine adjustments
The cursor keys move selected objects by 1 pixel, or snaps to grid if <Ctrl>
held, and vice-versa when 'Snap to grid' is active. This is a lot easier than
using the mouse.
• Group objects