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Questions tagged [hard-real-time]

A classification of real-time where missing a deadline is considered a total system failure.

From the real-time computing wikipedia page:

[T]he goal of a hard real-time system is to ensure that all deadlines are met... Hard real-time systems are used when it is imperative that an event be reacted to within a strict deadline. Such strong guarantees are required of systems for which not reacting in a certain interval of time would cause great loss in some manner, especially damaging the surroundings physically or threatening human lives (although the strict definition is simply that missing the deadline constitutes failure of the system).

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Differences between hard real-time, soft real-time, and firm real-time?

I have read the definitions for the different notions of real-time, and the examples provided for hard and soft real-time systems make sense to me. But, there is no real explanation or example of a firm real-time system. According to the link…
jxh
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Using Haskell for sizable real-time systems: how (if?)?

I've been curious to understand if it is possible to apply the power of Haskell to embedded realtime world, and in googling have found the Atom package. I'd assume that in the complex case the code might have all the classical C bugs - crashes,…
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Why Erlang is suitable for soft real-time applications, but not for hard real-time?

Or maybe it's good for hard real-time too?
bob
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Testing Real Time Operating System for Hardness

I have an embedded device (Technologic TS-7800) that advertises real-time capabilities, but says nothing about 'hard' or 'soft'. While I wait for a response from the manufacturer, I figured it wouldn't hurt to test the system myself. What are…
Nate Parsons
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What is a better approach to have realtime loop and non realtime function at the same time

Sorry for the bad title, I really don't know how to describe that in short... My scenario is that for a robotic application, we need a realtime loop to control the motor every 1ms. While at the same time we may want to do something that does not…
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Real-time programming with Linux

I've just built and set up a vanilla Linux kernel with the RT patch applied. Everything went fine and I can now correctly boot into the new kernel. What leaves me wondering is this: I have a simulator program that I've made in C, and I want it to…
Lawrence Ironjuly
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Are Real time systems Hard/Soft or the RTOS itself?

I just wanted to ask if there exists anything like a Hard-time RTOS or Soft-Time RTOS itself or is it the designer who defines a system as Hard-time or Real-time irrespective of the RTOS used?
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Hard real time in user space with preempt_rt patch

From: https://rt.wiki.kernel.org/articles/f/r/e/Frequently_Asked_Questions_7407.html Real-time only has impact on the kernel; Userspace does not notice the difference except for better real time behavior. Does it mean that if we write the…
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Is Firebase appropriate for hard real-time computation?

I recently came across Firebase and found it very interesting. Having read up on the differences between hard real-time and soft real-time, I am now curious as to whether Firebase is appropriate for hard real-time computation or not. My intuition is…
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