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New Raspberry Pi Model B+

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Re: New Raspberry Pi Model B+

#161

Post by vardump »

poizan42 wrote: post #62
vardump wrote: post #51

Earlier quoted context omitted.

Probably it supports L2 pause frames (type of flow control) just like nearly any other ethernet device?

Thanks, I suspected something like that existed. Edit: The Wikipedia article says: "By 1999, several vendors supported receiving pause frames, but fewer implemented sending them.[4][5] Pause frames have several disadvantages.". Any idea what the situation is like today?

I believe L2 flow control is pretty common.

Of course you're usually not going to see them even when using Wireshark etc., because they're handled at the MAC hardware level.

I'm not aware how to reliably determine whether link partner has L2 flow control / pause frames enabled. But at least you can check whether it's locally enabled:

Linux:

  ethtool -a eth0
macOS:

  ifconfig en0 | grep media
Windows Powershell:

  Get-NetAdapterAdvancedProperty
Alternatively you can check Control Panel / Network Connections / right click adapter + select Properties / click Configure / Advanced tab / Flow Control value.

Note that above only applies to wired ethernet, not wlan.

Re: New Raspberry Pi Model B+

#162

Post by Yaggo »

imtringued wrote: post #94
Yaggo wrote: post #77

Earlier quoted context omitted.

To clarify, the "3D video feature" is nothing more than being able to record simultaneously from two cameras and merge the video inputs into side-by-side H264 stream. Combined with hardware H264 encoding with delay of ~100 ms, this is very useful for certain applications (in my case, live 3D video broadcasting from UAV). I'm not aware of any other "tinkerer-friendly" board capable of that.

The hardware accelleration for H264 sounds interesting. Although 100ms is not as ideal as I want but it's reasonable. Is it actually possible to use this feature in practice? Are proprietary drivers an issue? Also is it possible to browse the web and e.g. watch videos on youtube with adequate performance on an RPi? (different topic)

> Is it actually possible to use this feature in practice? Are proprietary drivers an issue?

I've streamed 3D video over wifibroadcast¹ to OSVR headset, no fundamental issues. The exact lag depends on resolution, fps, etc settings. It would be superb to cut the delay to sub-50 ms range, but that's probably not going to happen as it would require major rewrite of the H264 stack, as currently there are always two full frames in the pipeline, e.g. in 30 fps it makes 1000/30*2 -> ~70 ms delay². (Note that I'm not the author of the befinitiv website.)

The foundation has released open-source driver stack³ (raspivid etc), but AFAIK they have rather limited resources for software development (single ex-broadcom developer?) and limited access to proprietary features (documentation?) of the Broadcom chipset. Many things work but I think the capabilities of the SOC aren't yet fully utilized.

> Also is it possible to browse the web and e.g. watch videos on youtube with adequate performance on an RPi? (different topic)

No personal experience, but RPi 3 should be okayish for lightweight desktop use (YMMV) with 1 GB of RAM being main limitation for multitasking.

[1] https://befinitiv.wordpress.com/wifibroadcast-analog-like-tr... [2] https://befinitiv.wordpress.com/2015/09/10/latency-analysis-... [3] https://github.com/raspberrypi/userland

Re: New Raspberry Pi Model B+

#163

Post by xienze »

xienze wrote: post #120
stdcall83 wrote: post #31

Gigabit ethernet over usb 2? Will never reach gigabit speeds...

Disappointed that there still isn't a dedicated Ethernet controller. I would rather have that at 100Mbps than "gigabit" over USB.

Why the downvotes? It's a legitimate criticism. USB Ethernet is slower and consumes more CPU cycles.

Re: New Raspberry Pi Model B+

#164

Post by safepants »

jimmies wrote: post #134
moftz wrote: post #127

Earlier quoted context omitted.

It would be even easier and less vague to just pop out the SD card, open up /etc/network/interfaces, and edit that to add your network. Pop it back in and go. This is what I've done when setting up a new raspberry pi image without having any peripherals attached to it. I ssh in, configure the system to my liking, then make an image of the SD card for future use. I could even turn this work into a script that download…

That's what the person did -- they put wpa_supplicant.conf to the boot partition -- but somehow the Pi wouldn't connect, and they had no way to debug it to figure out what went wrong.

i had this situation before but i realized i missed a critical step: adding wpa_supplicant.conf BEFORE first boot of the pi0w. Not saying it's the same issue, but i was scratching my head for a while there.

Re: New Raspberry Pi Model B+

#165

Post by olfactory »

tjoff wrote: post #149
nikofeyn wrote: post #106

Earlier quoted context omitted.

in general, i find the aggressive title changing on hacker news confusing. it’s been happening a lot recently where i can’t find a post by eye where i know i knew the title or where the title was changed away from the exact title of the linked post or article.

Indeed it is quite frustrating and I often wonder why someone would waste energy in updating titles for no apparent reason.

Mods with too much time on their hands and a god complex.

Re: New Raspberry Pi Model B+

#166

Post by tonylemesmer »

petecooper wrote: post #102
Tepix wrote: post #64

Earlier quoted context omitted.

Amlogic S905X boxes are the better choice for Kodi these days. You can installi LibreElec, they are cheaper than a Raspberry Pi 3 and they support 4K & HDR and have hardware acceleration for H.265 (HEVC) and VP9.

I've never been entirely comfortable with these HTPC boxes with factory-issued OS, especially connecting to a local network. Do you have any advice or feedback on Amlogic S905X-based boxes that can have the OS flashed to something more generic (Debian-based, ideally)? Thanks!

posted elsewhere on this thread: https://libre.computer/2017/12/03/performance-and-power-cons...

Re: New Raspberry Pi Model B+

#167

Post by TheOtherHobbes »

SmellyGeekBoy wrote: post #115
danellis wrote: post #10

> If you’ve been a Raspberry Pi watcher for a while now, you’ll have a bit of a feel for how we update our products. Model B... Model A... Model B+... When can we expect to see the Raspberry Pi Master and the Raspberry Pi Master Compact?

As a Brit who grew up in the 80s / 90s I got the reference, shame it seems to have gone over the heads of some people ;)

No Archipides yet.

Re: New Raspberry Pi Model B+

#168

Post by yorby »

DanBC wrote: post #117
Narishma wrote: post #41

Why was the title changed? It's misleading right now since there's already a Raspberry Pi Model B+ available for ages. Should be "New Raspberry Pi 3 Model B+" just like on the blog post.

It's normally better to email the mods, because I don't think they see these comments.

just report the comment... they are really quick then

Re: New Raspberry Pi Model B+

#169

Post by mncharity »

jimmies wrote: post #52
tzs wrote: post #49

Earlier quoted context omitted.

How about an I2S microphone [1]? Or a PDM microphone [2]? These hook up to GPIOs. [1] https://www.adafruit.com/product/3421 [2] https://www.adafruit.com/product/3492

That's another something I don't know that I don't know!

> That's another something I don't know that I don't know!

This is something we don't do well. Situational awareness and expert consults. As a society, field, and individuals.

From grounding elite groupthink, to systematic reviews in medicine, to programming language design, to hardware acquisition, to choosing a javascript library, or crafting its api, to choosing what to eat for lunch. Existing socio-technical infrastructure is painful to use, with highly and variably suboptimal results. And the more interdisciplinary the task, the worse the costs.

Opportunities for improvement are coming. Hybrid human-computer systems, so "I'm planning to do X, can I get a sanity check?" can be addressed with a mix of automation, and AI, and stats, and custom blends of variously-skilled/expensive human expertise.

But there are existing opportunities which are often not taken advantage of. Like maintaining personal review "committees" - people of various expertise to whom you can mention what you are up to, and hope to at least get back a "sounds good"/"have you thought of instead doing X". And like watching for opportunities to mention one's work on fora like HN, to create an opportunity for feedback. :) Engineered serendipity.

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