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Date: Wed, 17 Feb 2021 12:57:38 -0800
Subject: Re: [EE]:: Simple Task Scheduler written in C
Thread-Topic: [EE]:: Simple Task Scheduler written in C
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On Tue, 16 Feb 2021, Harold Hallikainen wrote:

> Thanks for posting! I've really gotten use to just using state machines
> with switch/case statements. Each "task" has an input FIFO that other
> tasks can dump complete messages into. When the main loop calls a task, i=
t
> immediately returns if there is nothing in its input FIFO. If there is
> something there, it acts on each message, generally outputting to other
> task input FIFOs. Not preemptive, but simple! If needed, priority of a
> task can be increased by putting it in the main loop more than once.

Hi Harold,

I respect your use of state machines (see my own use if you have the=20
slightest doubt :-)), however I think you might be interested in the=20
following. It is a simple implementation of co-routines (cooperative=20
multitasking) for the PIC16.

BEWARE you cannot call yield from inside a subroutine that has been called=
=20
via the hardware "call" instruction. BUT there is nothing to create your=20
own calling mechanism that circumvents the "call" instruction which is=20
itself similar to the "yield" macro.

I do something similar to this within the XCSB compiler.

Regards
Sergio Masci


--=20
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