L-DALI User Manual
115
LOYTEC
Version 5.2
LOYTEC electronics GmbH
o
ICMP
: Allows incoming ICMP packets (recommended).
6.1.10
User Registers
The device can be configured to contain user registers. In contrast to system registers, these
are only available as a part of the data point configuration. User registers are data points on
the device that do not have a specific technological representation on the control network.
Thus, they are not accessible over a specific control network technology.
A register merely serves as a container for intermediate data (e.g., results of math objects,
calculation parameters). The register can have the following, basic data types:
Double
: A register of base type
double
is represented by an
analog
data point. It can
hold any scalar value. No specific scaling factors apply.
Signed Integer
: A register of base type
signed integer
is represented by a
multi-state
data point. This register can hold a set of discrete states, each identified by a signed
stats ID.
Boolean
: A register of base type
Boolean
is represented by a
binary
data point. This
register can hold a Boolean value.
String
: A register of base type
string
is represented by a
string
data point. This register
can hold a variable-length character string in UTF-8 format.
Variant
: A register of base type
variant
is represented by a
user
data point. This
register can hold any user-defined data of up to a specified length of Bytes. This length
is defined when creating the register and cannot be changed at run time.
Since a register has no network direction, it can be written and read. Therefore, it is created
as a value data point by default. It is also possible to create two data points for each register,
one for writing the register (output) and one for reading the register (input). In this case a
suffix is added to the register name to identify the respective data point. For example, the
register
MyValue
will have two data points generated for:
MyValue_Read
and
MyValue_Write
.
6.1.11
Structures
Complex data belonging semantically together may be structured. The data point model
allows mapping structure types onto user-defined data points of
variant
type. This can be
necessary, if a network technology carries such structured data or if a user-defined register
shall provide structured data for access through a single data point. In any case, the structure
is modeled as a top-level data point and a hierarchy of sub-data points representing the
structure members.
The top-level data point is a user data point of variant data type. It contains the image of the
entire structure as a Byte array. Each structure field is then modeled as a sub-data point of
the appropriate class (e.g. analog, binary, or multi-state). A structure field may itself be a
structure going down one level in the hierarchy of sub-data points.
An example is shown in Figure 113. In this case a user register of two Bytes is bound to a
structure type mapping the two bytes on analog data points. The two sub-data points
byte_0
and
byte_1
.
Figure 113: Example of a structured data point.
