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Chapter 4
Managing Tasks
Chapter 4 Managing Tasks
Concept of a Task
The System 5000 takes a new approach to data logging. During setup, measurement
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parameters are assigned logical names (labels) such as AirTemp or Battery. These names are
referred to as Tasks in the System 5000
. Each Task can be assigned an input or source, such as
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an SDI-12 sensor or an A/D channel, as well as one or more outputs or destinations, such as a log
file or GOES transmission. The value retrieved from the input becomes the Task’s primary value
and will be passed along to any outputs assigned to that Task. In this manner, inputs and their
values can be easily identified by their Task names in both simple and more advanced setups.
Time vs. Event-driven Tasks
Most Tasks on the System 5000 will probably be set up and used based on a common scan
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rate. If a scan rate of 15 minutes was chosen and all Tasks were setup as such, every 15 minutes
the desired Inputs would be measured and the Outputs would be run. These events are based
purely on the time of day and are most common in data logging applications.
Unique to the digital ports on the System 5000 is the ability to be event-driven rather than
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time-driven. This means that if a digital port is assigned as the Input for a Task and designated
as Event-driven (based on the falling or rising edge), the Outputs for that Task would only be run
when the chosen port detected a falling or rising edge. A rain bucket, for example, that
momentarily closes a switch could be set as Event-driven with a log file as an Output. Every
time the rain bucket closes the switch, the date and time of the exact edge change would be
recorded.
System 5000
Managing Tasks 4-1
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