Rockwell Automation 1788-CN2FF ControlNet-to-FOUNDATION Fieldbus H1 Linking Device User Manual - Manual (Page 34)

1788-6.5.1 - January 1999
4-8 Using the ControlNet-to-FOUNDATION Fieldbus H1 Linking Device
That is, you may use channels CN_OUT_A3 and CN_OUT_A5 and not use
any of the others.
As shown in the lower loop of Figure 4.6, you can connect the MAO block
to any parameter that is a float value and status combination. In other words,
you can bring values from a PLC processor to any function block. The
MAO block is not limited to interfacing with AO function blocks.
ControlNet Analog Output Objects
The linking device creates an instance of a ControlNet AO object for every
wired channel in the MAO block instances. Each instance of the ControlNet
AO object has the attributes and access rules shown in Table 4.B.
Note that BkCalStatus is created only when the controller is capable of
participating in the CAScade initialization handshake and when the
BKCAL_OUT of the AO block is wired to a BKCAL_IN
x parameter of the
MAO block.
Only Value, CNStatus, casInstatus, ReadBack, and TagDesc are created
when an MAO is connected to something other than an AO function block
CAS_IN parameter.
Discrete Inputs This section describes configuration of the linking device to access any
discrete value (and status) in a Fieldbus device. It also describes the
attributes of the created ControlNet discrete input object.
Table 4.B ControlNet Analog Output Object Attributes
Attribute
Number Name Type Access Initial Value Remarks
3 Value Float Set 0 This is written from the ControlNet side.
4 CNStatus Boolean Set Bad ControlNet status. 0-Good; 1-Bad.
11 FailStateValue Float Set 0 The linking device writes the value to the AO
block when this attribute is changed by the
controller.
151 TagDesc String Get As configured Tag of the Fieldbus function block that this
object instance represents.
152 FailstateTime Float Set 0 The linking device writes the value to the AO
block when this attribute is changed by the
controller.
153 ReadBack Float Get 0 This represents the BKCAL_OUT value from the
AO block.
154 BkCalStatus uint8 Get Bad:Not-
Connected This represents the status of the Readback
attribute.
155 casInstatus uint8 Set Bad:Not-
connected This represents the status of the CAS_IN to the
AO block.