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Objects |
Smart devices using DNP protocol's Application Layer can monitor, control, or produce a large amount of data. This data, called information elements, is processed and stored as an information object, which is standardized to produce ways to describe it and represent it in a unique way. The types of categories for data objects are the following:
•Static Objects: These are objects that reflect the current value of a field or internal variable
•Event Objects: These are objects generated as a result of a value change or other trigger. These are historical objects, that is, they reflect a data value at an instant in the past
•Frozen Static Objects: Reflect a current frozen value of a field or internal variable. Data is frozen as a result of a data-freezing request
•Frozen Event Objects: These objects are the result of a change in a frozen value or other trigger. These are historical objects, that is, they reflect a data value at an instant in the past
Every category is represented by a different object, as described on the next table.
Categories of objects
Object |
Description |
|---|---|
Digital Inputs |
A group of digital inputs contains all objects that represent binary inputs (status or Boolean attributes). Ranges from 1 (one) to 9 (nine) |
Digital Outputs |
A group of digital outputs contains all objects that represent binary outputs or control information on relays. Ranges from 10 to 19 |
Counters |
This group contains all counter objects. Ranges from 20 to 29 |
Analog Inputs |
Contains all analog inputs. Ranges from 30 to 39 |
Analog Outputs |
Contains all analog outputs. Ranges from 40 to 49 |
Time |
Contains all objects that represent time in an absolute or relative form. Ranges from 50 to 59 |
Classes |
This group contains all objects that represent data classes or data priorities. Ranges from 60 to 69 |
Files |
Files or file system. Ranges from 70 to 79 |
Devices |
Ranges from 80 to 89 |
Applications |
Objects that represent operating system applications or processes. Ranges from 90 to 99 |
Alternative numbers |
Custom number representations. Ranges from 100 to 109 |
It is important to notice that a static object, when suffering a variation, is capable of generating an event object indicating that change. However, both represent the same object.