5 ms·
As someone that has played in the embedded world too, i struggled with that last year. But let's be honest. Except if you have really strong constraint about p
by di4na 10y ago
As someone that has played in the embedded world too, i struggled with that last year.
But let's be honest. Except if you have really strong constraint about power consumption and form factor, most of these small stuff are far easier to work with, perform probably better (because yes your software has bugs) and have so so so much better tooling.
Because the embedded world has a big tooling problem. I still hope to have some Rust on lower level to push it into the XXIst century.
And the nerves project is made by people that come from the embedded world. They completely know their limits and do not try to push it everywhere.
- new_hackers 10y agoI think "embedded" may be the wrong word. Perhaps "very low power" is the correct way to differentiate these things (e.g. RPi versus TI MSP430). I think that at this point they are both "embedded" since I would consider "embedded" to be anything without a keyboard and monitor (hence "embedded" inside another thing).
- qubex 10y agoSo a headless server is ‘embedded’? An old-school vector supercomputer that required a frontside host system is ‘embedded’? No, surely not: ‘embedded’ requires the notion of the computing system to be essentially a controller of a physical process or system, i.e., the component that controls a device or machine that operates in our actual physical world. It might very well possess a (perhaps rudimentary) screen and keyboard or keypad.
- planteen 10y agoI like that definition. I used to maintain a system most people would call true "embedded" - it was a PowerPC based VME system running VxWorks. The job of the system was to monitor some analog voltages, detect an unsafe condition, and open some relays if the unsafe condition was detected in < 10 ms. VxWorks dev tools and the PowerPC cards are very expensive, so we decided to replace it with a x86-64 server running RedHat MRG. That is the Linux kernel with the PREEMPT_RT patchset. We had a PCIe card in there for monitoring the analogs and firing the relays. Was the system still embedded? I would argue it was. The heart of the code was basically the same - VxWorks has the POSIX API for pthreads after all. There were just some driver call changes and init looked different.
- Cyph0n 10y agoThanks for mentioning VxWorks. It looks quite interesting, and I'm surprised that I haven't heard of it before!
- new_hackers 10y agoYou make a good point. But the old-school vector supercomputer was likely not very-low-power. That my general point, since very-low-power devices have different programming models than a more conventional OS based computer.
- rdtsc 10y ago> , the component that controls a device or machine that operates in our actual physical world. So is a an industrial factory control server embedded? It controls valves, actuators, reads sensors. It can still be a whole rack top to bottom full of high power Xeon servers. Embedded literally means inside something. It is not a computer used on its own, say to run general purpose software, but as part of another larger system. There is no power or size requirements for that. Well and most of all it is a fuzzy term.
- choosername 10y agothat would be a controller. embedded in a similar vein means that a controller or whatever is embedded in a bigger stand-alone system, and thus not it isn't stand-alone on its own. a desktop is stand-alone. A webserver isn't but the internet its part of isn' really stand-alone. Mobiles were called embedded, but newer phones with apps are rather stand-alone. All are embeddable.
- Cyph0n 10y agoNot only power consumption, but also for realtime applications, like those used in industrial and automotive control systems. In such scenarios, the overhead and unpredictability of the OS scheduler is unacceptable. When you want to say isolate a fault exactly 100us after it takes place, you can't have the OS executing that task at some different delay in a nondeterministic fashion.
- di4na 10y agowell in that case you enter a completely different world. Hard RealTime system are not really only "embedded". They also exists for bigger things. It is just a really different set of way to think. And a really hard one i may add.
- jacobush 10y agoHard realtime can also be with seconds latency, to further complicate things.
- jacobush 10y agoI used to but have come to accept that embedded nowadays mean anything which is black box like and does its thing. Can be Linux or a PIC program written in assembler.
- pjmlp 10y ago> I still hope to have some Rust on lower level to push it into the XXIst century. Well, there are some nice tools available, but not many seem to be willing to pay for them. http://www.mikroe.com/compilers/ http://www.mikroe.com/compilers/ http://www.astrobe.com/default.htm http://www.astrobe.com/default.htm http://www.ptc.com/developer-tools/apexada http://www.ptc.com/developer-tools/apexada