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Address of KOM process. The address must be a 16-bit number from interval 0-65 519 (other addresses have special meanings).

Serialization of communication with individual stations on the line. Serialization means that individual stations are queried sequentially (which corresponds to the situation of the stations on the serial line) to avoid conflict when multiple stations try to send a response at the same time. If a D2000 KOM process actually communicates with a single device that contains multiple virtual stations, or a device that is forwarding messages to other stations (in a way that prevents a conflict), or the channel is duplex (TCP, UDP), it is possible to disable serialization. Thus D2000 KOM process will send queries to all stations on the line and then wait for answers. Turning off serialization can speed up communication, but this will cause packet collisions and packet losses on lines with multiple stations where collisions are possible (such as RS-485).

The parameter determines whether, in addition to Poll requests for individual classes (Class 0-3), requests for the explicit reading of all supported object Groups should also be sent. The reason for the explicit reading of Groups is that some objects may not be assigned to any of the classes, so Poll requests will not find them.

The parameter activates advanced debug information about messages in the time queue.

Interval for sending Poll requests. It is possible to configure 4 different intervals and for each interval to specify the class to which Poll is sent (Class 0-3).
Each time a station is queried periodically (according to the settings specified in the "Time Parameters" tab of the Station type object), it is checked whether the specified interval has passed since the last Poll request was sent.
Note: In addition, Poll requests are also sent when the station reports available data (using the Internal Indications field that is present in the read/write responses).

10 for PI1-3

600 for PI4

The class to be queried within the n-th Poll request. There are four classes according to the standard:

• Class 0 (static data) - the response to Poll returns static data of objects belonging to all Classes 0-3
• Class 1 (event data high) - the response to Poll returns events (changes of values) of objects belonging to Class 1
• Class 2 (event data normal) - the response to Poll returns events (changes of values) of objects belonging to Class 2
• Class 3 (event data low) - the response to Poll returns events (changes of values) of objects belonging to Class 3

The default order for each parameter (Pol Class 1-4) is Class 1, 2, 3, 0. First, data (events) from the highest priority (Class 1, 2, 3) are read, then Static Data (for all Classes 0-3).

Maximum The maximum length of the data packet sent by process D2000 KOM - Data Link Layer packet (also called transport segment). This is data in Header Block, i.e. fields Ctrl (1B), Destination (2B), Source (2B) plus data in Data Blocks (in each max. 16 bytes). The Start (2B) and Length (2B) fields in the header, and the CRC (2B) fields in the header and each data block are not included in the length. The parameter can be in the range 10-255.

Maximum The maximum length of the Application Layer fragment sent by process the D2000 KOM process. The Application Layer fragment is a block of octets containing request or response information that is transmitted as one or more consecutive transport segments. The parameter can be in the range 15-1024.

Message sent to the outstation when establishing a connection. According to the standard, the message RESET_LINK_STATES (0) must be sent if confirmed messages are used (see Confirmation Mode parameter). If the parameter is set to NO, a REQUEST_LINK_STATUS (9) message will be sent.
According to the standard, REQUEST_LINK_STATUS (9) messages are recommended when using the DNP3 protocol on IP networks, i.e. within TCP and UDP messages.

If the parameter is set to YES, the station is in the receive-only mode (no messages are sent to it).

The number of request retries (1-20), if the station is not responding, or its response is corrupted.

The number of errors (missing or corrupted response) after which the station goes into a communication error.

The parameter activates the sending of spontaneous changes by outstations - function Unsolicited Response (130). The options are:

• Disabled - activation is disabled
• Class 1/2/3 - activation is performed by sending a message with function Enable Unsolicited Responses (20) to Classes 1, 2, 3

Note: Sending of spontaneous changes by multiple stations e.g. on the RS-485 bus can cause collisions.

The parameter enables confirmation of messages sent by process D2000 KOM. If confirmation is enabled, the outstation must acknowledge each application fragment (by application function 0 - CONFIRM).
According to the standard, confirmed messages should not be used on IP networks, i.e. within TCP and UDP messages.
If confirmation is enabled, the Reset Link States parameter must be set to YES according to the standard.

Delay The delay between receiving a station response and sending another packet. Delays can be used to artificially slow down communication (reduce/distribute the station's load).

The parameter activates verification by reading a value after writing. Readings will only be performed for the I/O tags with Explicit Read configured and a Write Type that does not return a value, i.e. Write (2) and Direct Operate Non Return (6).

The parameter disables the default cumulation of multiple Read and Poll requests within a single message. By default, the requests are cumulated until the data size reaches Max Fragment Length bytes.

Mapping of status bits (if they are included in a received message) to the I/O tag value. Options are:

• WEAK Attribute: Status bits are mapped to the WEAK attribute
• Flags (FLA..FLH): Status bits are mapped to FLA to FLH user flags
• WEAK + Flags: status bits are mapped to both WEAK attribute and FLA to FLH user flags
• None: status bits are ignored

Different variations within different groups have different status bits. All except the ONLINE bit indicate a problem.

Individual groups and their variations have the following status bits:

(GXvY stands for Group X variation Y, GXvY-Z stands for Group X variation Y through Z - see Table 1)

G1v2, G2v1-3, G3v2, G4v1-3, G10v2, G11v1:

• Bit 0: ONLINE
• Bit 1: RESTART
• Bit 2: COMM_LOST
• Bit 3: REMOTE_FORCED
• Bit 4: LOCAL_FORCED
• Bit 5: CHATTER_FILTER (always 0 for G10v2, G11v1)

G20v1-4, G21v1-8, G22v1-8, G23v1-8: 

• Bit 0: ONLINE
• Bit 1: RESTART
• Bit 2: COMM_LOST
• Bit 3: REMOTE_FORCED
• Bit 4: LOCAL_FORCED
• Bit 5: ROLLOVER
• Bit 6: DISCONTINUITY (always 0 for G20v3-4, G21v3-4, G21v7-8, G22v3-4, G22v6-8, G23v2-4, G23v7-8)

G30v1-2, G30v5-6, G31v1-4, G30v7-8, G32v1-8, G33v1-8, G40v1-4, G42v1-8:

• Bit 0: ONLINE
• Bit 1: RESTART
• Bit 2: COMM_LOST
• Bit 3: REMOTE_FORCED
• Bit 4: LOCAL_FORCED
• Bit 5: OVER_RANGE
• Bit 6: REFERENCE_ERR

Reverse mapping of the ONLINE flag. Since this is the only flag in the DNP3 protocol that means normal status (all other flags indicate problems), its reversion when mapping to the FLA flag may be useful (so the FLA flag is set if the ONLINE flag is 0, i.e. device is offline).

Enables separation of Frozen Counters namespace from Counters - i.e. I/O tags in the Frozen Counter (21) and Frozen Counter Event (23) groups will have separate addresses from the Counter (20) and Counter Event (22) I/O tags. According to the standard, Frozen Counters and Counters share a common space, but a specific implementation of the DNP3 protocol required this separation.

Encoding The encoding used to convert objects from Octet String (110) group to text strings. Supported encodings are:

• UTF-8
• ISO-8859-1 (identical mapping without conversion)
• Windows-1250
• Windows-1251
• Windows-1252

High level of communication logging with information about individual I/O tags.