Browse Prior Art Database

Combining Non-synchronous Processes in a Real Time Task

IP.com Disclosure Number: IPCOM000107432D
Original Publication Date: 1992-Feb-01
Included in the Prior Art Database: 2005-Mar-21
Document File: 2 page(s) / 60K

Publishing Venue

IBM

Related People

Marshall, LB: AUTHOR [+2]

Abstract

Disclosed is an algorithm for combining two non-synchronous data-consuming processes into a single real-time task capable of running under a real-time operating system.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 63% of the total text.

Combining Non-synchronous Processes in a Real Time Task

       Disclosed is an algorithm for combining two
non-synchronous data-consuming processes into a single real-time task
capable of running under a real-time operating system.

      Some real-time tasks (such as a modem datapump) are based on
two non-synchronous functions, one for transmitting and another for
receiving.  These asynchronous processes can be coupled in such a way
that it is impossible to divide the functions into separate tasks
under an operating system without introducing unacceptable delays.
This invention allows these asynchronous processes to run as a single
task under a real-time operating system.

      To reduce system overhead and achieve optimum efficiency, a
real- time task should process the largest data block possible during
each execution period (frame). For sampled signals, this data block
represents a unit of time during which the task must also process
another block of samples based on different clock with a slightly
different frequency.  Furthermore, many signals may be grouped into
modulation intervals that serve as a basis for the block size
definition.  The samples contained in a modulation interval must be
processed together.  Therefore, the block size is typically chosen to
be an integral number of modulation intervals.  In this invention the
task frame size is chosen to compensate for the tolerance of the
clocks.

      An example of a task performing this ty...