But in situations where the PC is either over burdened or underpowered, the speed at which screens are displayed can become a problem.
It's most often experienced as a several second delay from the press of a menu button to the loading of the selected screen.
And while many users believe they have to live with these delays, in most cases a simple work-around can be used to speed up display loading dramatically.
By default, when the “display” command is executed the graphic display called must be loaded from the hard drive, displayed and animated.
If the issue being experienced is the time it takes to load and display the graphic, the simplest solution is to “cache” the display in RAM.
However, this method only reduces the loading time after the screen has been displayed the first time.
Because of this, some users have taken to preloading all slow loading displays using a start-up macro.
This is done using the below command once for each screen you want to be preloaded into memory:
Display “My Screen Name” /Z
Always updating cached displays
When this is the case, you may wish to not just cache the display, but also set it to always update.
This will not only keep the display in RAM, but it will continue to poll the tags on the display as well.
The downside is the continued polling of the tags on a screen not being displayed.
On a slow network you may not have the bandwidth needed to poll tags on the currently displayed screen as well as several cached displays.
If you decide to use this option you can enable it in the display settings menu for each graphic display, or you can use the below command in a start-up macro:
Display “My Screen Name” /ZA
One final note on caching displays
One side effect of this is when you edit a display that is cached, you won't actually see your changes until cached is cleared or the project is restarted.
Thankfully, Rockwell included a “Flashcache” command in View to help in these situations.
This command issued by itself will flush all displays from the cache.
However, you can also use this command to flush a single display from the cache. To do so, you just issue the command along with the display you would like to flush (Flushcache “My Screen Name”.)
I hope you've found the above information about resolving slow loading graphic displays helpful.
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