Allen-Bradley 2080-LC20-20AWB, User Manual

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8
Rockwell Automation Publication 2080-UM005E-EN-E - March 2018
Chapter 2 About Your Controller
Using Run Mode Change
(RMC)
Run Mode Change (RMC) is a productivity enhancement feature introduced in
Release 8 for Micro820/Mico830/Micro850 controllers. It saves the user time by
allowing logic modifications to a running project without going to remote
program mode and without disconnecting from the controller. It requires the
Connected Components Workbench Developer Edition release 8 software to use
this feature.
RMC is useful when the user is developing a project by incrementally adding
small changes to the logic and immediately wants to see the effects of the changes
on the machine. With RMC, since the controller stays in remote run mode, the
controller logic and machine actuators will not have to constantly reinitialize,
which can occur if the controller is switched to remote program mode (for
example, first scan bit is checked in program logic to clear outputs).
When user is editing, building, and downloading a project without using RMC, a
full build of the entire controller project is performed and also a full download of
the project is performed. During RMC an incremental build is performed and
only incremental changes are downloaded to the controller.
RMC is performed incrementally at the end of every program scan in order to
prevent a large delay in the program scan. This adds up to an additional 12 ms to
the scan time. For example, if the program scan is normally 10 ms, it may increase
to 22 ms during RMC until the update is finished. Similarly user interrupts may
be delayed.
IMPORTANT
Micro820/Micro830/Micro850 controller firmware revision 8.xxx or
higher is also required to use Run Mode Change.
IMPORTANT
Do not disconnect from the controller after performing Run Mode
Change, do a full build, and try to reconnect. Connected Components
Workbench will treat the project in the controller as different from the
project in Connected Components Workbench, and ask to either upload
or download even though the logic is identical.
Example of the Benefits of Using RMC – 20% Reduction in Download Time
Number of
Changes
Time to Perform Conventional
Download (seconds)
Time to Test Logic and
Accept Changes (seconds)
1 36 29
5 180 130
10 360 255
Memory size of project used for comparison:
Data = 14784 bytes; Program = 2352 bytes
Note: The duration starts when the RMC button is clicked while connected to the controller and ends
when the accept is finished. For example:
1. When connected to the controller, click RMC
2. Modify program
3. Click Test Logic
4. Click Accept to finish, or click Test Logic to make another change