Newbie Question: FreeRTOS (on an Uno) - Single execution Task

Does anyone know of a task that will execute once then block? I would like to be able to "unblock it" (using the task handle) for reuse later.

The examples I have tried all run periodically, I guess I could use a semaphore to indicate when to trigger but wondered if there was a specific task type that solved this problem. I am looking in the reference guide but I am only 108 pages into the 380; besides, I do not know what term to search for.

Design intent:

  • Trigger a simple FET switch controlling a relay on an ad-hoc basis from other tasks.
  • Read a K-Type thermocouple interface (SPI) periodically, updating a "current temp" global variable.
  • Respond to an EarthLCD touchscreen touch event within 250 ms.
  • Update an EarthLCD display periodically.
  • Manage a simple user interface; use cases, states, operator modes...

Thank you in advance for any help, even if it is an admonishment to "RTFM" as long as you reference the requisite "FM".

David W. Arlington, VA