OPTO 22 SNAP-PAC-R1, Руководство пользователя

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CHAPTER 3: SYSTEM INFORMATION
SNAP PAC R-Series Controller User’s Guide
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The I/O Side of the Controller
The controller reads and writes to the I/O points using its I/O side memory map. This side of
the SNAP PAC R-series controller is like SNAP EB-series brains.
You can think of the controller’s memory map as a grid of mailboxes, with each mailbox
having its own memory address. Each mailbox address has a specific purpose. For example,
one address holds the state of a single digital point; another address holds counter data for
the same point. There’s an address that stores the controller’s firmware version, one that
contains the minimum value of a specific analog point, and many more. If you are familiar
with programmable logic controllers (PLCs), you’ll see that the memory map is similar to a
register.
Most SNAP PAC R-series controllers run PAC Control flowcharts that automatically
manipulate the memory map, so you probably won’t need to understand it in detail. If you
do need to refer to it, however, the complete list of memory map addresses is in Opto 22
form 1465, the
OptoMMP Protocol Guide .
The Control Side of the Controller
The control side of the controller is like a traditional Opto 22 industrial controller. In the
control side, the controller runs PAC Control flowcharts. These flowcharts provide the logic
that controls processes through the system. Commands within the flowchart read from and
write to the memory map in the I/O side of the controller in order to monitor and control
the I/O points.
Controlling the System
The flowcharts that run in the control side of the controller are created in PAC Control, a
software application included with the SNAP PAC R-series controller. You create these
flowcharts as part of a
control strategy and download the strategy to the controller, and the
The rack is shown with the SNAP
PAC R-series controller on the left
and the input/output modules on
the right.
The modules on the rack connect
to devices in the real world, such as
the light bulb, to monitor or control
them.