Very Computer

by **General Accou** » Fri, 14 Apr 1995 04:00:00

Reply - Multitasking Real-Time Kernel

Dear James,

I saw your posting in comp.arch.embedded asking about your interest in
finding an O/S that you could use educationally to change the policies
of the scheduler.

General Software makes a DOS that has a multitasking microkernel inside.
It implements threads, timers, mutexes, events, and higher level objects.
Full source code is provided for the entire system and you can develop
application programs with standard DOS tools (Borland or Microsoft C++
for example). The company sells most of its products to manufacturers
of commodity embedded systems (used in cars, phones, faxes, copiers, etc.)

Product Development Group
General Software, Inc.
tel: 206.454.5755
fax: 206.454.5744

by **E. Douglas Jens** » Sat, 15 Apr 1995 04:00:00

>I saw your posting in comp.arch.embedded asking about your interest in
>finding an O/S that you could use educationally to change the policies
>of the scheduler.
>General Software makes a DOS that has a multitasking microkernel inside.
>...
>Full source code is provided for the entire system...

So is your proposal that James change the scheduling policy by changing
the source code, as opposed to this OS having a scheduling policy
interface into which he could plug arbitrary scheduling policies?

Doug

--------------------------------------------------
Doug Jensen from home

Voice +1 508 653 5653. Fax +1 508 655 4790

by **billd..** » Sun, 16 Apr 1995 04:00:00

writes:

> Reply - Multitasking Real-Time Kernel

Is this the same General Software that ships Embedded DOS? If so, be warned,
imho their product is very very poor. I had a brush with it earlier this year.
It is buggy, and the documentation is a joke. All of which was aggravated
by their local distributor who did not get enough memory to run BC45 until
after I had abandoned the product. On the other hand, if youare really
determined, I'll happily sell my license to you, on a non-returnable basis.

On the other hand, PharLap's TNT DOS Extender provides multi-tasking, albeit
with a small limitation they assure me they will be overcoming shortly.

This does seem to be a difficult area.

Bill Davy

by **Jean J. Labross** » Fri, 12 May 1995 04:00:00

Have you also considered 'uC/OS, The Real-Time Kernel'? uC/OS is
an ideal RTOS for teaching the internals of a real-time kernel to
students. My book: 'uC/OS, The Real-Time Kernel' provides the
full source code for the kernel (also available on diskette) and
also tells you how it works internally. uC/OS is a fully
preemptive, multitasking, ROMable RTOS. All kernel services are
'deterministic' and scheduling does not depend on the number of
tasks running (i.e. scheduling is constant). You can get my book
and diskette from R&D Publications for $54.95. To order, contact

0-13-031352-1).

Also, you could also get my other book called: 'Embedded Systems
Building Blocks' (ISBN 0-13-359779-2) which contains a collection
of highly portable C module for embedded systems. This book
contains all the source code (and also comes with a diskette) and
cost only $39.95.

Jean J. Labrosse