Siemens S7-200 - Hardware and Software Components

Siemens S7-200 Driver
l Network Mode:This property is used to control how channel communication is delegated. In Load
Balanced mode, each channel is given the opportunity to communicate in turn, one at a time. In
Priority mode, channels are given the opportunity to communicate according to the following rules
(highest to lowest priority):
l Channels with pending writes have the highest priority.
l Channels with pending explicit reads (through internal plug-ins or external client interfaces)
are prioritized based on the read's priority.
l Scanned reads and other periodic events (driver specific).
The default is Load Balanced and affects all virtual networks and channels.
Devices that rely on unsolicited responses should not be placed in a virtual network. In situations where
communications must be serialized, it is recommended that Auto-Demotion be enabled.
Due to differences in the way that drivers read and write data (such as in single, blocked, or non-blocked
transactions); the application's Transactions per cycle property may need to be adjusted. When doing so,
consider the following factors:
l How many tags must be read from each channel?
l How often is data written to each channel?
l Is the channel using a serial or Ethernet driver?
l Does the driver read tags in separate requests, or are multiple tags read in a block?
l Have the device's Timing properties (such as Request timeout and Fail after x successive timeouts)
been optimized for the virtual network's communication medium?
Channel Properties - Master ID
Master ID: Specify the node number used by the Siemens S7-200 Driver on the network. Each channel must
have a unique Master ID. The valid range is 0 to 126.
Device Properties
Device properties are organized into the following groups. Click on a link below for details about the settings
in that group.
General
Scan Mode
Communication Timeouts
Auto-Demotion
Redundancy
Device Properties - General
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