Industrial Engineer · phase 3 of 16 · noun

Task

Execution container that schedules one or more programs by cyclic, periodic, or event-driven rules.

The Explain card

Plain English
A task is the scheduler's unit. It decides when a set of programs runs, whether continuously, on a fixed period, or when a specific event fires.
Example
A controller has a continuous task for the main machine logic, a 10 millisecond periodic task for a fast counting routine, and an event task tied to a motion interrupt.
Why it matters
Tasks have priorities, and a fast periodic task starves a continuous task if it does too much work. Where logic sits decides how often it runs and how fresh its I/O is, so it is a design decision and never an afterthought.
Hook
The task is the clock the program keeps.

Word knowledge

How the word is built, where it came from, and what it sits beside in memory.

In a sentence

The engineer assigns the 10 ms motor interlock program to a high-priority periodic task before commissioning the conveyor drive.

How it is built
  • task root a duty or piece of work
Where it came from
Origin
Middle English taske, from Old North French tasque and ultimately Medieval Latin taxa, meaning a tax or charge
Entered the language
c. 1300
What changed
The sense moved from an imposed payment or duty to assigned work, then to a scheduled unit in computing and control systems.
How it is spelled
Pattern
The final -sk represents the consonant cluster /sk/.
Pattern
In General American English, a before -sk commonly represents /æ/.

Spelled like

  • mask
  • flask
  • bask
Broken into chunks
  • task
    • tasked
    • tasking
    • taskmaster
What it sits beside

Same subject

Same shape

IEC 61131-3 program organization units

PLC timing terms

Where it sits in the deck

Phase 3: PLC Program Organization and Execution

How the logic is arranged and how the scan actually runs it, which is the difference between code that works and code that works every time.

Neighbours in this phase