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Protocol PAK (GPT) Source Code Library Knowledge Base

Knowledge Base

The Protocol PAK Knowledge Base is an accumulated collection of responses to common support questions submitted to our technical support staff during customer implementation of various protocol source code libraries. Following is a list of these support questions. Click on the Item that best fits your situation to download an associated document.

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Knowledge Base
Item Title Protocol Description
1 IECPT Transmission of Class 1 and 2 data IEC 870-5-101 Provides additional help for understanding transmission of Class 1 and Class 2 data, including rules for scheduling and inclusion of specified point types.
2 IECPT Balanced Mode IEC 870-5-101 Contains additional help to users deploying the IECPT in balanced mode.
3 Revision Numbering All Explains meanings of source code library code?release revision numbers
4 Replacing Test DAC Routine All Describes how DAC test software can be replaced with user written modules
5 Accumulator Freeze and Reset All Explains interface between library and customer code related to accumulator freeze and freeze-and-reset commands
6 IndacticPT Indication Processing Indactic 33/41 Explains how class 1 and class 2 digital point events are handled within Indactic 33/41 protocol
7 IECPT Comm Interface IEC 870-5-101 Clarifies interface to the customer written serial communication API (COMM) for IEC 870-5-101 protocol
8 Assigning DNP Variables to an Event Class DNP3 Clarifies point assignments to DNP3 event classes 1, 2 and 3
9 Resource Management All Provides details on resource management, memory allocation, and thread execution
11 Analog Deadbands All Describes analog deadband processing both for protocols that directly support this feature, and for those that assume deadband values are configured within the RTU
12 Request Processing All Clarifies how selected requests are passed into the GPT for processing. Includes explanations for GetObject, Read, Write, Read Events, Ack Events, and Write Events.
13 Smart Communication All Explains how the user can improve communications efficiency by parsing data-link layer messages in the COMM, instead of the GPT
14 DAC Variable offsets All Describes how the GPT views static data managed by the user application
16 Master Mode Commands IEC 870-5-101 Describes how to issue communication requests when operating a master mode PT component, with emphasis on IEC 870-5-101 protocol
20 Control Translation All Presents an example for passing a control from a master PT computer to a slave PT component, and is useful when two separate protocols have been purchased for the purpose of building a protocol translation package. Examples are provided for IEC 870-5-101 protocol, but also apply to other protocols.
21 DNP3 Master Mode DNP3 Provides hints for implementing DNP3 Master Mode protocol
22 IEC Variable Change Processing IEC 870-5-101 Describes how to force variables (points) to be included in a Class 2 poll response, based on the point having changed value
24 IEC Master Mode Event Processing IEC 870-5-101 When operating in master mode, describes now time-stamped event processing is impacted by the value of IPROP_IEC_SYSTEM_QUEUE
25 IEC Master Clock Sync IEC 870-5-101 Explains how to process clock synchronization requests in IEC 870-5-101 master mode
26 IEC System Queue Processing IEC 870-5-101 For IEC 870-5-101 translation mode, explains how to move events from the system queue to individual data processing routines.
28 Telegyr Data Objects Telegyr 8979 Clarifications on coding data objects for Telegyr 8979 protocol
29 DAC Static and Event Writes All Explains table structure differences relative to accessing input point data for event change processing and for static data reporting. Information presented is applicable to master mode operations.
30 PGandE Read Time PG&E 2179 Explains processing of the PG&E 2179 protocol "Read Time" function
31 IEC Controls IEC 870-5-101 Presents details on processing control output requests for IEC 870-5-101 protocol
32 IEC Counter Interrogation IEC 870-5-101 Presents details on processing IEC 870-5-101 counter interrogation requests
33 Dial-Up Circuits All Describes how to interface to a dial-up communication environment
34 Version 3.0 Upgrade All Describes issues upgrading from Protocol PAK releases 2.9 and earlier, to releases 3.0 and later. Migration between these two levels occurred during the end of 1999 and beginning of 2000
35 IEC Parameter Handling IEC 870-5-101 Describes handling of IEC 870-5-101 ASDU Types used for passing parameter data
36 Request Optimization Several A class of protocols allows multiple DAC Requests to be transmitted as a single request. Examples of protocols that support this feature include DNP3, Telegyr 8979 and SES92. This document defines a number of possible approaches to optimize processor usage when this capability is used
39 GPT Scheduling All Describes various ways of providing executing time to the Protocol PAK environment, in order to support configuration into a wide range of real-time operating system strategies
43 IEC Sample Code IEC 870-5-101 Instructions for configuring a basic user DAC interface, designed for the new Protocol PAK user
44 Network Communication Several Instructions for configuring user communication code for network (LAN/WAN) operations
45 Modbus Master Debug Modbus Hints for debugging Modbus messages when operating in master mode



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