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up vote 8 down vote

added by Nick Nov 26 '14 at 15:12

up vote 7 down vote

added by SF. Jul 9 '14 at 10:25

up vote 4 down vote

added by Gilles, edited by WikiSpeedia hang-around Aug 2 '14 at 11:07

up vote 4 down vote

added by dennisschagt Jul 26 '14 at 16:06

I would rephrase this: What causes processor X to fail at a certain clock rate. Am I not giving it enough power, is it the physical limits/propagation delay of the clock signal, can I cool it more adequately to run it faster? – Nick Aug 15 '14 at 21:46

up vote 3 down vote

added by Niall C. Jun 15 '14 at 17:07

up vote 2 down vote

added by Gilles Jun 8 '14 at 2:50

up vote 2 down vote

added by Gilles Jun 8 '14 at 2:53

up vote 2 down vote

added by SF. Jun 9 '14 at 13:26

up vote 2 down vote

added by user3715487 Jun 25 '14 at 13:35

I think this question should be changed to "How can I avoid writing low level drivers on the MSP430". Because you do not need an RTOS for that - just a HAL (which TI provides already for free). This question, as is, shows a misunderstanding about what an RTOS comprises. If this were an actual Q&A I would answer the question in that manner and suggest that the OP edit their post to make this a better / more targeted question. – Nick Nov 18 '14 at 21:47

Thanks for the suggestion, I changed it. What you said makes sense. I actually liked writing the low level drivers for my MSP430, but I thought someone might want to know the answer to this. Or maybe a specific driver they don't want to write, like the ADC or GPIO or I2C bus. Maybe they are hoping for a better driver already written? – user3715487 Nov 25 '14 at 4:19

Writing drivers can be loads of fun, it can also take loads of time. This is a perfectly valid question because using prewritten drivers can save a lot of development time and for most engineers who work for a living and are expected to get stuff done that's important! But I still always advocate review, refactoring, and testing prewritten drivers! – Nick Nov 26 '14 at 15:08

up vote 2 down vote

added by Ahmed Khalaf Jul 28 '14 at 16:07

up vote 2 down vote

added by Bruno Ferreira Nov 9 '14 at 0:05

up vote 2 down vote

added by Nick Dec 9 '14 at 21:56

up vote 1 down vote

added by BenjiWiebe Jun 9 '14 at 21:24

up vote 1 down vote

added by Niall C. Jun 11 '14 at 3:56

up vote 1 down vote

added by David Freitag Jun 18 '14 at 20:39

up vote 1 down vote

added by Patrick Jul 22 '14 at 13:34

I'm wondering what it takes to run an Ada application on an MCU like the Atmel SAM4S, but the question applies to any processor. I think a full-fledged OS like Linux is not possible on a small MCU -- can a minimal Ada application (but with tasking) still be built if some primitives are provided? – Patrick Jul 22 '14 at 13:38

up vote 1 down vote

added by lgeorget Jul 29 '14 at 17:04

Which version? There are three different ones, and they all have different processors. – Clearer Oct 12 '14 at 22:01

up vote 1 down vote

added by Mahendra Gunawardena Sep 7 '14 at 15:09

	Great question -- I was just trying to figure out how to do this (and debug with gdb). I'm out of votes, but I like the question. – Patrick Dec 29 '14 at 22:57
	You can downvote an upvote and upvote this questions :-) Just kidding lets get forum to the next stage first. – Mahendra Gunawardena Jan 1 '15 at 0:59

up vote 1 down vote

added by Keelan Oct 26 '14 at 9:37

up vote 1 down vote

added by Keelan Oct 26 '14 at 9:38

up vote 1 down vote

added by DHH Oct 29 '14 at 23:41

The manual would be linked, of course. – DHH Oct 29 '14 at 23:42

up vote 0 down vote

added by thejohnny Jun 7 '14 at 18:53

	Why is this downvoted? Please could people leave comments. – Rocketmagnet Aug 7 '14 at 14:11
	The question is a bit vague and shows a lack of research. Is this referring to physical layer, the serial protocol, or perhaps the file system? With the first two you wont have any wiggle room and it will depend on specifically which card you are trying to interface with - so it would be a datasheet answer. – Nick Nov 24 '14 at 23:19

up vote 0 down vote

added by BenjiWiebe Jun 9 '14 at 21:24

This will generate a lot of data sheet / wiki answers. – Nick Aug 15 '14 at 21:43

up vote 0 down vote

added by David Freitag Jun 18 '14 at 20:37

up vote 0 down vote

added by Nick Aug 15 '14 at 22:02

	Real world example I've faced: The production system will ship with Li-SoCL2 cells because of their shelf life and energy density. But lithium primary cells are class 9 hasmat and can't be shipped by plane and can be a pain to ship by boat or ground as well. They are also trouble to store and dispose of. So the requirement came: Allow the user is to also load the system with Alkaline Cells. Especially for Sales Demos, Trade Shows, Beta Trials, Engineering R&D - anything where you do not really need the life span of that Li-SoCL2. – Nick Nov 24 '14 at 23:28
	This question is orthogonal to embedded systems programming. This is a purely EE.SE question. – Nick Alexeev Dec 23 '14 at 7:20
	@Nick-Alexeev I agree with you that this is orthogonal to embedded systems programming. In posting this question I am asking "Is a purely hardware question OK here?". "Proposed Q&A site for professionals and enthusiasts of embedded hardware and software." The definition of this stack includes hardware to draw in a bigger audience. I agree this is a better question for EE.SE, but if a question like this comes up when Q&A starts should it be moved, or is it okay to keep it here? I've deliberately asked a couple of what I feel are 'good' hardware questions to test the will of the community. – Nick Dec 23 '14 at 17:52
	Actually, I believe the right solution to this is a dedicated "battery charger" microcontroller (there are some models with builtin hardware just for this job) running the right software to support different chemistries and manage power from them. – SF. Jan 17 '15 at 1:25

up vote 0 down vote

added by Oilyraincloud Aug 19 '14 at 15:58

The original question was more EE related asking about the limits of flash chips. – Oilyraincloud Aug 19 '14 at 17:03

up vote 0 down vote

added by Makouda Oct 4 '14 at 18:54

up vote 0 down vote

added by fanl Oct 6 '14 at 0:55

up vote 0 down vote

added by Patrick Dec 19 '14 at 19:08

up vote 0 down vote

added by Mahendra Gunawardena Jan 2 '15 at 12:38

up vote 0 down vote

added by Mahendra Gunawardena Jan 2 '15 at 12:41

up vote -1 down vote

added by Rocketmagnet Jun 7 '14 at 23:35

If you phrase this as "What are the benefits of using Linux on an Embedded System" (as opposed to something more barebones), this will fit. – mirabilos Jun 9 '14 at 21:20

Benefits as opposed to what? – Gilles Jun 9 '14 at 22:19

@mirabilos - Er, that sounds like the same question just re-worded. – Rocketmagnet Aug 7 '14 at 14:13

Erm yes, the idea was to reword it to be not as broad. "embedded Linux" is a bit different from "Linux on an embedded device". – mirabilos Aug 8 '14 at 13:31

up vote -1 down vote

added by Ahmed Khalaf Jul 28 '14 at 16:10

up vote -1 down vote

added by Nick Aug 15 '14 at 21:13

Please, no shopping questions. – Keelan Oct 26 '14 at 9:35

This isn't a shopping question. It is a "what type of enclosure question". E.G. I can put a circuit board in adhesive heat shrink and it does a very good job as a water proof enclosure for a short period of time. I will edit the question to make it more clear that this is not a product recommendation question. – Nick Oct 27 '14 at 14:45

Why the second down vote? Do your embedded systems consist of just a PCB sitting on a bench or do you need to put them in some sort of enclosure? If your embedded system does indeed need an enclosure then how is a discussion about enclosures not relevant for this stack? Why would a discussion about making an environment proof enclosure be off topic for this stack? – Nick Oct 29 '14 at 16:45

Real life example: A university research project about crickets. I do not know the specifics about what they were hoping to learn (perhaps it was pest control related). But the project was to have a sensor (transducer) + data logger that could be buried in the dirt for a few months and could listen for cricket chirps. The solution was wrap it in adhesive heat shrink. Then after recovery we would cut the shrink wrap off, pull the SD card and read the data, then replace the SD Card / battery, replace the heat shrink and redeploy the sensor. Is that sort of discussion relevant here? – Nick Oct 29 '14 at 16:54

If you're going to downvote this question - please give some reasoning to why you think this question is off topic for this site!! What you are effectively saying when you downvote a question like this is that this isn't a Q&A site for the limited amount of mechnical engineering that typically goes into embedded systems projects. This question has had 4 downvotes with no explanation, two of them after I've given real life examples. Is this question not interesting, is it inappropriate, why the downvotes? – Nick Nov 24 '14 at 23:01

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up vote -1 down vote

added by DHH Oct 10 '14 at 2:53

up vote -1 down vote

added by Clearer Oct 12 '14 at 21:53

	The question is equally valid for using components of your own design, partially or completely, as well as for designing those components to begin with.. – Clearer Oct 12 '14 at 22:04
	This would be better asked on Electrical Engineering – DHH Oct 24 '14 at 1:02

up vote -1 down vote

added by Roflo Nov 14 '14 at 2:44

up vote -2 down vote

added by Rocketmagnet Jun 7 '14 at 23:35

	This isn't a question, it's a class of questions. Yes, these questions would be on-topic — but Area 51 works best by asking as close to actual questions as possible. Please read the FAQ section on “What makes good questions?”, especially “Ask real, expert questions” and “Ask questions that can be answered”. – Gilles Jun 9 '14 at 22:16
	“How can I facilitate debugging on an embedded system without the ability to echo variables to a screen when a debugger interferes with fast loops?” is an example of a good question on this topic. – Gilles Jun 9 '14 at 22:21

up vote -2 down vote

added by Gilles Jun 8 '14 at 2:52

up vote -3 down vote

added by Rocketmagnet Jun 7 '14 at 23:37

This question is too broad. You can't compare the size of apples and oranges. You can compare the size of a specific apple and a specific orange. – Gilles Jun 9 '14 at 22:11

No, this is a good question. It generated some very helpful answers when it was asked on the original site. – Rocketmagnet Aug 7 '14 at 14:12

Could this question be rephrased: Where do performance hits in RTOSs come from? Or, how can I estimate the performance loss (%) due to context switches if I use an RTOS running N threads that need to run X often for X long. – Nick Aug 15 '14 at 20:51

I believe the right approach would be "What's the performance hit of [RTOS] vs [non-RT version]?" - comparing RTLinux to plain Linux would be a specific apple and orange. Trying to compare QNX to Windows Server wouldn't really work. – SF. Jan 17 '15 at 1:10