User Manual

Logical I/O blocks
Discipline I/Os
19
270 | 353 CM110664en_07
L= DeviceType DeviceNo.GroupIndex(3RD[NVIndex.FieldIndex])
● DeviceType: M (Master). There are no slaves (S) with third-party devices
There is only ever one device.
● DeviceNo: Field device identification number
● GroupIndex: Group identification: Up to 4 similar groups of an application
unit may exist in the field device (e.g., lighting or window-blind groups). The
group index number is optional.
● ObjectType: Constant for third-party devices: 3RD.
● NVIndex: Network variable referenced in the third-party device.
● FieldIndex: Element number, if the network variable is structured
KNX addressing
You can integrate data points from KNX devices as follows:
● See
PX KNX, RXB integration - S-Mode (CM1Y9775)
● See
PX KNX, RXB/RXL integration - Individual addressing (CM1Y9776)
● Address Info LED for PX KNX: D=1001
19.7 Discipline I/Os
Discipline I/Os are standardized combinations of inputs and outputs related to
a specific application. They have a predefined number of parameters.
Three different input variable types can be interconnected to Discipline I/Os:
● Simple value
● Trigger value
● Commandable value
The input value can be connected via the data flow. In the engineering tool, this
is preceded by a function block or compound, e.g., a Scheduler. However, if the
input value is not connected, it can also be modified via BACnet client. The
subsystem registers a change in the input value by comparing the value with
the process image and transferring it to the field devices.
This input value is the logical image, or memory map, of an analog positioning
command and describes its properties. Within the program, the Present Value
is made available to the block as a program value. The block transfers the
program value to the subsystem, from where it is transmitted to the field
device.
Writing to this value acts as a trigger. This makes it possible, e.g., to generate
the output of the same value (e.g., Lighting 100%, followed later by 100%
again). In this case the subsystem registers the trigger value and transmits the
value to the devices. This capability is required when the same variable can be
modified from several sources (e.g., when Desigo CC writes 100.0%, the local
operator unit writes 0.0% and the Desigo CC user wants to rewrite the value of
100.0%). The sources can be BACnet clients or system function blocks.
Only analog trigger values may be used.
The input value is the logical image, or memory map, of an analog positioning
command and describes its properties. Within the program, the Present Value
is made available to the block as a program value. The block transfers the
program value to the subsystem, from where it is transmitted to the field
device.
The commandable value is based on the BACnet priority-mechanism (which is
the same as for the output blocks – refer to Section 0). A commandable value
can be operated from various sources. Each source has its own priority. The
sources are mutually exclusive (interlock). The source with the highest priority
prevails, e.g., Emergency = Priority 1, Façade control = Priority 6, Operator =
Priority = 8). The sources can be BACnet operator units or system function
blocks (grouping function).
Addressing via standard
I/O
Simple value
Trigger value
Commandable value