MultiTrode MultiSmart Installation & Operation Manual page 171

MultiSmart Installation & Operation Manual
24.3.1.14 Ramp
This function block can be used to generate a ramp output. It receives four values as inputs. They are the
SVAL- Starting Value (DINT), EVAL – Ending Value (DINT), STIM – Starting Time (TIME) and ETIM –
Ending Time (TIME). It returns a Boolean result ACT, indicating whether the Ramp function is currently
running and DINT output, RES which shows the current value of the ramp output.
24.3.2 Low Level Functions & Function Blocks
Low level functions and function blocks give direct access to the MultiSmart tag database. As such, they
offer great flexibility and power for ISaGRAF programs.
understanding of the tag database.
The MultiSmart tag database has three types of tags:
1. Status tags – these include Analog, Digital, Integer, Fixed-Point, Date, and String tags.
2. Command tags – these include Analog Control and Digital Control tags, and are used for sending
commands to various processes.
3. Configuration tags – these include Boolean Attribute, Date Attribute, Integer Attribute, Fixed-Point
Attribute, and Sting Attribute tags, and are used for configuration of various processes. As such, that
values of these tags are stored in non-volatile memory, such that these values can be restored if the unit
restarts.
24.3.2.1 CommitSetPoint
Command tags and configuration tags all consist of a set point and value. When you write to one of these
tags, the set point is modified. This does not actually effect any change in the unit until the value is also
updated.
The CommitSetPoint function block can be used to update the value of a command or configuration tag
with its modified set point. It receives the full name of the tag as an input, together with a Boolean variable
which defines whether the function block should be activated. It then returns a Boolean result, indicating
whether the operation was successful.
24.3.2.2 RollbackSetPoint
This function block performs the reverse of the CommitSetPoint function block. It is used to reject set
point changes.
24.3.2.3 IsSetPointPending
This function block is used to determine whether a set point change has been made to a command or
configuration tag. It receives the full name of the tag as an input. It then returns a Boolean result, indicating
whether the set point is pending for the selected tag.
24.3.2.4 ReadBoolSetPoint
This function block can be used to read the value of Digital, Digital Control, and Boolean Attribute tags. It
receives the full name of the tag as an input. It then returns a Boolean result indicating whether the
operation was successful, together with the value of the selected tag.
24.3.2.5 ReadBoolValue
This function block can be used to read the value of Digital, Digital Control, and Boolean Attribute tags. It
receives the full name of the tag as an input. It then returns a Boolean result indicating whether the
operation was successful, together with the value of the selected tag.
24.3.2.6 ReadFloatSetPoint
This function block can be used to read the set point of Analog Control and Fixed-Point Attribute tags. It
receives the full name of the tag as an input. It then returns a Boolean result, indicating whether the
operation was successful, together with the set point of the selected tag.
MultiSmart_IO_Manual_A4_v2-22_R15.doc
However, their use requires a more detailed
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