I/O tags - processing a value acquired from the communication

An object of the I/O tag type allows to configure configuring a sizeable quantity of parameters, which determine the procedure of processing of so-called "raw" value acquired from communication. This document describes in detail individual processes steps for each of the value types separately. The listed information can helpful during analysis and comparison of values with process level and for programmers and users of the open interface D2000 KomAPI open interface.

Processing of a new value of the I/O tag is executed by calling performed withing the call of PointNewValue call-back function of the interface the D2000 KomAPI interface.

Value types of I/O tags in the D2000 system: DI, AI, CI, TIR, TIA, QI, TXTI, DOUT, AO, CO, TOR, TOA, TXTO.

Kotva
type_di type_di

DI value type

If the entered value is valid ("Valid" status bit is adjustedset) and the value is not the a default one (the "Default" status bit is not adjustedset), the following will be executedperformed:

• Polarity inversion of this input value will be performed if "Inverse" polarity is adjusted configured (the Polarity tab, Logical polarity parameter in a particular I/O tag configuration dialog box).

Value The value is ignored if the I/O tag is in default value mode. For further information see the Default value chapter.

Value A value change check in comparison  is carried out, comparing the value with the previous state will be carried outone. If a change has been performeddetected, then the value is sent to the D2000 Server after processing the process alarm checkalarms.

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type_ai_ci type_ai_ci

AI, CI value types

In the case of AI type, at first, if the value is valid, the validity check of the number in the floating-point form format is executed. If the number is not valid, then the invalid value is sent to the D2000 Server.

If the entered value is valid ("Valid" status bit is adjustedset) and the value is neither the default one (the "Default" status bit is not adjustedset) nor simulated, there the following steps will be executedperformed:

• Conversion to technical units (None / Linear conversion / Polynomial conversion / Pt 100 conversion). Value The value of CI type is converted to a real number in the floating-point form format and after the conversion to technical units it is converted by in a saturation mode way back to the cardinal integer form.
• Value filtering (None / First order filter / Out of limits values are undefined / Value kept always in limits).
• Filtering according to based on the defined value absorption.
• Filtering according to based on the defined dead band.
• State check of value limitsValue limits are checked.

Value The value is ignored if I/O the tag is in default value mode. For further information see the Default value chapter.

Value A value change check in comparison  is carried out, comparing the value with the previous state will be executedone. If a change has been performeddetected, then the value is sent to the D2000 Server after processing the process alarm checkalarms.

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type_ti type_ti

TIR, TIA value types

If the entered value is valid ("Valid" status bit is adjustedset) and the value is neither the default one (the "Default" status bit is not adjustedset) nor simulated, there  the following steps will be executedperformed:

• Conversion to technical units (None / Linear conversion) in case of TIR type.
• Value filtering (None / First order filter / Out of limits values are undefined / Value kept always in limits) in case of TIR type.
• Filtering according to based on the defined dead band in band in case of TIR type.
• State check of value limits in Value limits are checked in case of TIR type.

Value The value is ignored if I/O the tag is in default value mode. For further information see the Default value chapter..

Value A value change check in comparison  is carried out, comparing the value with the previous state will be executedone. If a change has been madedetected, then the value is sent to the D2000 Server after processing the process alarm checkalarms.

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type_qi_txti type_qi_txti

QI, TXTI value types

Value The value is ignored if I/O the tag is in default value mode. For further information see the Default value chapter.

There will be executed the A value change check in comparison  is carried out, comparing the value with the previous stateone. If a change has been madedetected, then the value is sent to the D2000 Server after processing the process alarm checkalarms.

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type_dout type_dout

DOUT value type

Value The value is ignored if I/O the tag is in default value mode. For further information see the Default value chapter..

There will be executed the A value change check in comparison  is carried out, comparing the value with the previous stateone. If the change was performeda change has been detected, then the value is sent to the D2000 Server after processing the process alarm checkalarms.

Kotva
type_ao_co type_ao_co

AO, CO value types

If the value is valid, the following steps will be executedperformed:

• Conversion to technical units (None / Inverse linear conversion). Value The value of CO type is converted to a real number in the floating-point form format and after the conversion to technical units it is converted by in a saturation mode way back to the cardinal integer form.
• If the "Transient" status bit of the value is not adjustedset, then the state check of the value limits check will be executedperformed.

Value The value is ignored if I/O the tag is in default value mode. For further information see the Default value chapter.

Value A value change check in comparison  is carried out, comparing the value with the previous state will be executedone. If a change has been performeddetected, then the value is sent to the D2000 Server after processing the process alarm checkalarms.

Kotva
type_to type_to

TOR, TOA value types

If the value is valid, there the following steps will be executedperformed:

• Conversion to technical units (None / Inverse linear conversion) in case of TOR type.
• State check of value limits in Value limits are checked in the case of a TOR type.

Value The value is ignored if I/O the tag is in default value mode. For further information see the Default value chapter.

Value A value change check in comparison  is carried out, comparing the value with the previous state will be executedone. If the change was performeda change has been detected, then the value is sent to the D2000 Server after processing the process alarm checkalarms.

Kotva
type_txto type_txto

TXTO value type

Value The value is ignored if I/O the tag is in default value mode. For further information see the Default value chapter.

There will be executed the A value change check in comparison  is carried out, comparing the value with the previous stateone. If a change has been madedetected, then the value is sent to the D2000 Server after processing the process alarm checkalarms.

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limits limits

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Value limits check

The check is also executed internally for CI and CO types in the floating-point form. Check Checking of limits is executed, to verify the validity of the condition:

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If not (wrong values of dynamic limits), the "LimitsProblem" limit flag is set, on the contrary an own check regarding the otherwise, processing of the hysteresis and setting of a particular limit flag will be executed.

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change_val change_val

Value change check

Value change check, compared that is comparing the value with the last status value that is was acquired from communication, is used to eliminate data quantity that is sent among reduce the number of data changes that are sent from the communication process and to the D2000 Server and from the D2000 Server and to other client processes of the D2000 system, such as process the D2000 HI process, fully in the sense of DODMaccordance with the DODM design. The check proceeds as follows:

• If the new value is valid, then the check of own values the value is executed. If the previous value is other than differs from the new value, the "NoAckValue" status bite bit is adjustedset.
• Check of state status flags.
• State check Check of limits.
• State change Check of process alarmsalarm change.
• If the ST_TIME_CHANGE flag is set to in the calling call of PointNewValue function of the interface the D2000 KomAPI interface, then the generation time check of the time of previous and the new value will be executed.

If any of the condition mentioned above is met and the new value is other than differs from the old one, then this the new value is sent to the D2000 Server.

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default default

Default value

Default The default value is initialized activated by:

• enabling Use default value option,
• enabling Force default value on HardError option during when the state change status of parent - station changes from ST_COMMERR into ST_HARDERR state or after the evaluation value of the I/O tag invalid state acquired from communication is evaluated as invalid,
• Operator an operator from process the D2000 HI process, if it is they are allowed to him/her by means of enabled activate the default value by the Switch to default value option.

All valid values acquired during communication with the device -(station) are saved and in case of the cancellation of manual the default value (by the operator from process the D2000 HI process or by means of disabled disabling the Use default value option) they are immediately sent into the system.

All the mentioned abovementioned options are configured in the Default value tab of the I/O tag control window.

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