ProSoft Technology ProSoft i-View - Manual (Page 35)

ProSoft i-View ♦ Mobile Process Monitoring and Control Application Data Source Files
Version 2.0.2 User Manual
ProSoft Technology, Inc. Page 35 of 106
September 29, 2011
Allen Bradley ControlLogix controllers can be plugged into any slot on the
backplane.Ethernet/IP messages can be sent "connected" or "unconnected". The
following attributes can be used to determine these characteristics. These are global
attributes.
EIP/NATIVE GLOBAL
ATTRIBUTES
TYPE DESCRIPTION
controller_slot number Identifies the slot where the Logix controller is located.
Default value is 0.
connected_mode number
(boolean) When true, ProSoft i-View will use "connected
messaging" instead of the default "unconnected
messaging" for retrieving data from Ethernet/IP enabled
PLCs. Look below for a discussion on what possible
effects you might expect. Default value is ‘false’.
ProSoft i-View currently supports two EIP mechanisms to send commands to AB PLCs:
(1) For a Micrologix or SLC it will send PCCC commands (DF1) embedded in EIP using a direct
path.
(2) For a ControlLogix/CompactLogix it will send native CIP commands using a Backpane, Slot-
Number path. The Backpane defaults to 1 and the Slot number is given in controller_slot.
ProSoft i-View uses CIP Explicit Messages to retrieve and send data from/to Ethernet/IP enabled
PLCs. Explicit messages can be sent "unconnected" or "connected". "Connected" messages
require a Connection ID which is first asked to the PLC before sending other messages, while
"unconnected" messages identify the specific path to the destination in the same message.
Connected messaging is generally considered to be more reliable than unconnected because it
reserves buffer space for the message, and is therefore less likely to be blocked by other
message traffic. However, if the TCP link between the message originator and the receiver is
weak or prone to fail, unconnected messaging may be a better choice. Wireless spots or carrier
networks can easily drop due to lack of coverage or weak signal, in these cases connected
messaging communications may take longer to reestablish after a fault, resulting in less overall
reliability and more user perceived delays than unconnected messaging. ProSoft i-View uses
unconnected messaging by default, but you can set it to use connected messaging for a source
file by setting the connected_mode attribute to true.
Note that since the Controller_slot attribute is a global one, it applies to the whole source file. This
is in contrast to the Slave_id attribute for Modbus, which only applies to the tag next to it. Also,
note that since different protocols cannot be mixed in the same source file, the two attributes are
incompatible between them, and the non-relevant one will be ignored.