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<div><div style="direction: ltr;">I’ve seen Nuttx used at 2 companies, and both regretted it. I’ve never personally used it, but people who did from both companies said the same thing: it’s a buggy, poorly documented and supported project. Its included drivers that were supposedly complete had gaping holes in them.</div><div><br></div><div style="direction: ltr;">I heard enough that I won’t touch Nuttx myself. </div></div>
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<div class="gmail_quote">On Mon, Feb 18, 2019 at 8:50 AM -0500, "Pete Soper via TriEmbed" <span dir="ltr"><<a href="mailto:triembed@triembed.org" target="_blank">triembed@triembed.org</a>></span> wrote:<br>
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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">Hi Huan,<div> I'm curious how external interrupt handling works with Nuttx layered on top of Linux? The last layered system I looked at along these lines used poll system calls by the app with file descriptors to detect state changes triggered by the hardware interrupt seen by the Linux kernel. The "realtime" attribute was right out the window with this because the Linux scheduler was involved so latency was effectively random up to multiples of milliseconds. Even if a thread could be bound to a core it was impossible to see how to achieve hard real time app layer response to a hardware interrupt with Linux. So I'm curious how Greg has cracked this nut. :-)</div><div><br></div><div>But I know many of us are curious to know what you're scouting RTOS choices to implement?</div><div><br></div><div>Pete</div><div>PS In case it's unfamiliar to others, "hard realtime" is jargon that implies a strict guarantee of timing tolerances and that no, meeting the spec 99% of the time is not success. But we don't know if that's relevant here. I'm just biased about systems bandying about "RTOS" when in some circumstances they are "WTOS" with the "W" standing for "whenever, man, but usually we're cool". :-)</div><div><br></div><div style="font-size:100%;color:#000000"><!-- originalMessage --><div>-------- Original message --------</div><div>From: Huan Truong <htruong@tnhh.net> </div><div>Date: 2/18/19 1:54 AM (GMT-05:00) </div><div>To: Mike Lisanke <mikelisanke@gmail.com> </div><div>Cc: Pete Soper <pete@soper.us>, Triangle Embedded Interest Group <triembed@triembed.org> </div><div>Subject: Re: [TriEmbed] NuttX </div><div><br></div></div>There is even a lovely Youtube channel that one of the developers (I<br>think?) talk about getting various things done on NuttX. I like his<br>easy-to-follow video style, and the menuconfig is my favorite of<br>NuttX.<br><br>https://www.youtube.com/channel/UC0QciIlcUnjJkL5yJJBmluw/videos<br><br>I have just ordered a Electron Photon board which they say they<br>support to test out. I recently worked with the ESP32 and was really,<br>really impressed by how organized and easy to get things done with<br>FreeRTOS on ESP32. At the same time, having being able to port real<br>Linux programs to it is going to be a huge boon for me.<br><br><br><br><br>On Sun, Feb 17, 2019 at 7:41 PM Mike Lisanke via TriEmbed<br><triembed@triembed.org> wrote:<br>><br>> Small footprint AND not Owned by Amazon :-p<br>><br>> On Sun, Feb 17, 2019 at 2:59 PM Pete Soper via TriEmbed <triembed@triembed.org> wrote:<br>>><br>>> On 2/17/19 2:04 PM, Huan Truong via TriEmbed wrote:<br>>><br>>> Anyone worked with NuttX? This is the first time I've heard of NuttX<br>>> when I searched for FreeRTOS and NuttX came up.<br>>><br>>> https://www.embedded.com/electronics-blogs/say-what-/4458729/What-is-the-NuttX-RTOS-and-why-should-you-care-<br>>><br>>> "NuttX is a POSIX RTOS. You don’t need to learn a new API to program<br>>> it. You can write an application in a POSIX Operating System like<br>>> Linux or MacOS, validate it, and then compile it to run on NuttX. If<br>>> you don't want to create an application from scratch, you can grab<br>>> some small Linux libraries and perform some minor modifications to get<br>>> them working on NuttX."<br>>><br>>> Hi Huan!<br>>><br>>> I'd never heard of it. The detail of the porting guide is impressive. The fact that it was originally written by one person is (IMO) a major plus and that person appears to be VERY active (retired in Cost a Rica?). With a highest number of 128 there are only 12 open issues in the BitBucket repo. And this todo list is really interesting. It<br>>><br>>> -Pete<br>>><br>>> That sounds a really compelling reason to me to use it.<br>>><br>>> PS: I hope everyone is doing well in NC. I haven't found a group quite<br>>> like ours in Bay Area yet.<br>>><br>>> - Huan.<br>>><br>>> _______________________________________________<br>>> Triangle, NC Embedded Computing mailing list<br>>><br>>> To post message: TriEmbed@triembed.org<br>>> List info: http://mail.triembed.org/mailman/listinfo/triembed_triembed.org<br>>> TriEmbed web site: http://TriEmbed.org<br>>> To unsubscribe, click link and send a blank message: mailto:unsubscribe-TriEmbed@bitser.net?subject=unsubscribe<br>>><br>><br>><br>> --<br>> Best regards, Mike<br>> _______________________________________________<br>> Triangle, NC Embedded Computing mailing list<br>><br>> To post message: TriEmbed@triembed.org<br>> List info: http://mail.triembed.org/mailman/listinfo/triembed_triembed.org<br>> TriEmbed web site: http://TriEmbed.org<br>> To unsubscribe, click link and send a blank message: mailto:unsubscribe-TriEmbed@bitser.net?subject=unsubscribe<br>><br><br><br>-- <br><br>Huan Truong<br>www tnhh.net / twitter @huant<br>
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