RTOS

Hi,

RTOS is Real-Time Operating System. It means a response time for urgent event is small enough and response connot be delayd.

See pSos or QNX RTOS for example. As rule RTOS is commercial product.

luck

You wrote: "It means a response time for urgent event is small enough and response connot be delayd."

You're speaking of so-called hard real-time operating systems where a late response is as bad - or worse - than no response at all. The RTOS in a guided missile would be such an example.

Not all RTOSes are hard systems - although it would certainly be nice if everything executed on time and under budget!

"Real-time" does not necessarily mean "fast." It means only "as fast as necessary." For example, to an ocean-tide-height monitoring instrument "real-time" might mean taking a measurement every ten or fifteen minutes or so, more or less, depending on if it's good and feels like it. On the other hand, to a missile guidance system ten or fifteen microseconds might seem like an eternity.

The RTOS doesn't have to be fast, just fast enough.

-e

ok :)

For all most RTOS. It's more exactly if we say. RTOS response time for event is constant (depends on OS, settings etc). And we always know when we exactly get response on our event. It can be 15 minutes or 15us ...

There is no need for the RTOS in a guided missile. There is no time to spend on OS work. It's made by state machines in hard. Algorithms are not so branchy. And missile "live" time is several second only... It's quite another matter for cruise missile...

CompVision wrote: "... It's quite another matter for cruise missile..."

Not only cruise missiles, but for "intelligent" unmanned weapons in general. Weapons are getting smarter all the time. Too bad the same can't be said for Man.

-e

Search on Real Time Operating Systems.

These are programs, typically running on embedded processors, that manage the execution of software programs or functions. The concept with Real Time OS is to allow different functions to operate as if each function is running on its own processor. However, there is typically only one processor and the different programs that are executing are time sliced among the CPU. In this way events can be managed so that no one program or function is late to the party, so to speak.

On a grand scale, the program called Windows on your PC is just a form of a RTOS that orchestrates events that your programs need to work. On smaller processors (microcontrollers) Real-Time has a special meaning where things are event driven based on input and output activity of the microcontroller.

One very good RTOS to learn about is called "microCOS". It is actually written as uCOS with the letter U really being the Greek lowercase letter for mu.

There are two platform for RTOS. One is windows and the other is Linux.

Pre qualification for RTOS is Program knowledge in C & C++. Embedded system course offered by reputed institutes like CMC. Best of Luck.

You wrote: "There are two platform for RTOS. One is windows and the other is Linux."

What an odd statement.

By "platform" do you mean "development environment" on which the code meant to execute under the RTOS is cross-developed, or do you mean something else?

By the way, Linux is not the only "ux" workalike out there. Solaris, for example, is not Linux. Neither is BSD Linux. Neither is Unix (and it's variants) Linux?

And what about OS X? What do you think the iPod's RTOS was developed under? WinDoze?

Cheers!

-e

Linux is unpopular (at least to my area) can you describe the advantage and disadvantage of this operating system?

thanks..

MPD wrote: "can you describe the advantage and disadvantage of this operating system?"

Two advantages of Linux, for starters:

1) Reliability. We have several Linux-based servers which have been running for years without downtime. None of our Windows-based servers can make that claim (or come even close, for that matter). Linux is often the choice where mission-critical systems are concerned.

2) Open source. You know what you're getting because you can see it - all of it. With a proprietary OS who the hell knows what's buried in there? If something breaks, you can go in and fix Linux yourself (unless you don't have the sources, in which case you can download them from any number of mirrors). With Windows, for instance, you have to wait...and wait...and wait until the next triply-delayed patch or release in which M$ has added more bells, more whistles, more bloated code, rearranged the bugs, and added new ones.

3) Innovation. Lots of it.

Disadvantages of Linux:

1) Linux requires the user to be computer-savvy. Major distributions like Red Hat are getting better all the time, but Windows is still simpler to install and configure.

2)

-e

Hi

Uhhh, I think that is the acronym for "Real Time Operating System"

I would "Google" it, there is a lot of info there.......

Btw, Lady Stealth, "acronym" is itself an acronym: Alphabetic Co-location Reducing Or Numbing Your Memory. - The Devil's DP Dictionary

DUH...

I appologize if I was rude.... I'm sorry... Late night here

No offense taken.

I think the use of acronyms can be CRIMINAL.

Confused Regional Interpretation of Multilingual International Nomenclature and Acronymic Language.

I think I must be spending too much time writing responses to CR-4 posts!

Masu-san wrote: "I think I must be spending too much time writing responses to CR-4 posts!"

Nah! And you'd better not leave! Without your quality posts this place'd fall to pieces! (fueled by my BS posts, no less). At least post during daylight hours (Sydney time); you've got that new scope to evaluate and I expect a full report by Friday (but please, please keep it to less than 10 pages as I'll soon have a lot of papers to grade). Finals Week!

-e

Thankyou for the complement.

Speaking of RTOS, do you remember a certain Star Trek (original series) episode which featured an old librarian named Atoz? In the episode the planet's star was about to go nova, and so the entire population evacuated by means of travelling back into the planet's past with the help of the librarian. The particular era to which one travelled was determined by the choice of a metal disk which represented a chapter in the planet's history. Atoz inserted the disk into a machine that created a portal to the specific era. All the traveller had to do then was to walk through a special doorway and, voila!, they'd be there..er..then.

Sometime later it occurred to me that the librarian's name really stood for "A to Z."

So, might RTOS just be another way of saying zero?

It's Saturday, the sun is shining, birds are singing, I'm still in my pajamas, the coffee tastes particularly good this morning, and Smirky W. Chimp hasn't gotten us into a nuclear war with the Canary Islands. So what the hell?

-e

While I am on my own and working on my computer I normally have the TV running in the background usually tuned to something like The Discovery, National Geographic or History channel.

Anyway for some reason I was flicking through the channels and low and behold there is Mt Atoz explaining to Captain Kirk, Spock and Dr McCoy that they are terribly late and must choose quickly.

It's over 40 years old and the acting is pretty mediocre but the story lines are still pretty good and fun to watch.

I thought it was "regenerative thermal oxidizer" - fancy acronym for incinerator.