Re: Ada Run-time for embedded systems

[cwarack@kirk.usafa.af.mil (Chris Warack <sys mgr>)]

In article <INFO-ADA%95020710124203@VM1.NODAK.EDU>, CONDIC@PSAVAX.PWFL.COM writes:
|> From: Marin David Condic, 407.796.8997, M/S 731-93
|> Subject: Re: Ada Run-time for embedded systems
|> Original_To:  PROFS%"SMTP@PWAGPDB"
|> Original_cc:  CONDIC
|> 
|> 
|> 
|> "Theodore E. Dennison" <dennison@ESCMAIL.MMC.ORL.COM> Writes:
|> >
|> >l107353@cliffy.lfwc.lockheed.com (Garlington KE) wrote:
|> >>
|> >> Actually, there's a lot of COTS being used in embedded systems these days;
|> >> it's just that "embedded" means more than those weaselly little processors
|> >> used in avionics like ICNIA (or like I still use today :). For example,
|> >> C3I workstations are often called "embedded" systems since they are part of
|> >> a larger system. Many of these environments use extensive COTS databases,
|> >> display managers, etc.
|> >>
|> >Gimme a break!
|> >
|> >Show me someone who refers to a workstation setup as an "embedded
|> >system" and I'll show you someone who is trying to pad his resume'.
|> >
|> I have to agree. While one might easily call a workstation based
|> application "realtime" it's hard to imagine it as being
|> "embedded". If you define "embedded" losely enough, you could
|> call a payroll application on an IBM mainframe a "realtime",
|> "embedded" system. After all, it's "embedded" in a factory system
|> which semi-automatically takes raw materials in at one end of the
|> building and squirts out widgets from the other end. And it
|> happens in "realtime" because paydays happen on the 1st and 15th.
|> And they're "hard" deadlines in that missing them could result in
|> a riot which would destroy the widget producing platform...

That's true, but embedded isn't defined that loosely.  According to
DoD, that's a data processing system.

An embedded system is a critical part of a weapon system (at least from
the DoD perspective).  For example:

You have several large satellite tracking antennas attached to a room full
of receivers, demuxes, and decommutators, attached to a network of work
stations (with or without keyboards and monitors) attached to a communications
processor attached to a dedicated network.  Hanging off the work stations is
another network of user stations based on a work station with two or three
monitors, keyboard, keypad, and pointing device.  The sole purpose of all of
this stuff is to control some satellites and process the data they collect.

That, is an embedded system...  albeit a very big one.

The only reason the main processing work stations have keyboards and monitors
is diagnostics, on-machine control, and maintenance.  It's easier that way.

The reason to use work stations is obvious ----- cost.

|> I don't know how y'all would like to define what an "embedded"
|> system is, but I'd say that if it has a screen, QWERTY keyboard
|> and a mouse, we're _probably_ not talking about one.

But you might be... :-)  Also think Air Traffic Control, submarines, and 
ships as well as satellite ground stations.

I doubt you can argue for a clear, black and white distinction between
embedded and non-embedded.  In USAF, anyways, it seems pretty easy.  If
it's general purpose or data processing (does IM or DP stuff), then its
not embedded.  In the rest of the world, I don't think it'd be that easy.

-- 
Christopher A. Warack, Capt, USAF
Computer Science Department, US Air Force Academy

cwarack@kirk.usafa.af.mil                (719) 472-2401