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General Discussions => Tech Talk => Topic started by: Captain Video on February 10, 2019, 02:48:33 PM

Title: Raspberry Pi
Post by: Captain Video on February 10, 2019, 02:48:33 PM
Every once in a while I get jealous of another country.
I'm lucky to have a Microcenter near where I live which has a great  small electronics section but the idea of an Apple like Raspberry Pi store gets me very excited.

https://techcrunch.com/2019/02/07/the-raspberry-pi-store-is-much-cooler-than-an-apple-store/?utm_source=tcfbpage&sr_share=facebook&fbclid=IwAR2APXdO2qtKudE5WK4BC5cGqNYPN0Chj1mBbhoFxZw2ItlYPFlWjmD-quo

Quote
The Raspberry  Pi Foundation just unveiled a brand new project — an actual store. If you live in Cambridge in the U.K., you can now buy a bunch of sweet Raspberry Pis with which to tinker and develop some cool stuff.

I would hope there is a place close by where you can get meat pies to get the full British Pi(e) experience during a visit.

https://www.youtube.com/watch?v=QLBVAUo586A

Title: Re: U.K. Pi(e)s
Post by: Harry Black on February 10, 2019, 04:40:39 PM
Aww. I thought this was going to be about meat pies.
Title: Re: U.K. Pi(e)s
Post by: daniel1948 on February 10, 2019, 05:01:37 PM
I was hoping for Apple pies. But that’s okay. I have 3/4 of a half pie I bought yesterday. I’ll have another slice today.
Title: Re: U.K. Pi(e)s
Post by: BAWRFRS on April 24, 2019, 02:04:20 PM
Every once in a while I get jealous of another country.
I'm lucky to have a Microcenter near where I live which has a great  small electronics section but the idea of an Apple like Raspberry Pi store gets me very excited.

https://techcrunch.com/2019/02/07/the-raspberry-pi-store-is-much-cooler-than-an-apple-store/?utm_source=tcfbpage&sr_share=facebook&fbclid=IwAR2APXdO2qtKudE5WK4BC5cGqNYPN0Chj1mBbhoFxZw2ItlYPFlWjmD-quo

Quote
The Raspberry  Pi Foundation just unveiled a brand new project — an actual store. If you live in Cambridge in the U.K., you can now buy a bunch of sweet Raspberry Pis with which to tinker and develop some cool stuff.

I would hope there is a place close by where you can get meat pies to get the full British Pi(e) experience during a visit.

https://www.youtube.com/watch?v=QLBVAUo586A

Thanks for sharing. I'm a Pi enthusiast, but I don't fit the mold very well, as I don't really care about physical computing nor coding. I am keen to get better at Linux though and move away from Windows PCs (Apple too, if I can swing it). I'm hoping I'm on my last PC. My desktop tower is something like 8.5 yrs old. My backup is a 6 yr old Dell laptop that now runs Raspberry Pi Desktop.

MicroCenter ... nerd paradise. Nearest one to me is 100mi, but it's kind of dumpy IMO. An excellent one is near where my son attends college. There's online of course, too.

There's a video online with a time lapse of the building of the Cambridge store. Pretty neat. The video you linked is amusing to me in that although it has an Apple-store-like feel, there's still the tangle of wires to and from the pi and keyboard/mouse/monitor. That's where the elegance ends, but that doesn't bother some of us.
Title: Re: U.K. Pi(e)s
Post by: Alex Simmons on April 24, 2019, 04:41:19 PM
It does sound like a hobby I might be interested in one day, but I have no idea where to start. And more importantly no real clue as to what I would create with it. I've read articles along the lines of "top 10 raspberry pi projects" but none of them appeal to me.

What do people here do with their Pis?
Title: Re: U.K. Pi(e)s
Post by: BAWRFRS on April 24, 2019, 10:18:17 PM
It does sound like a hobby I might be interested in one day, but I have no idea where to start. And more importantly no real clue as to what I would create with it. I've read articles along the lines of "top 10 raspberry pi projects" but none of them appeal to me.

What do people here do with their Pis?

As implied in my post, I feel similarly to you w/r/t RPi projects. It's intended for CS education, and it is extremely well-suited to that role.

For me, the Pi is literally a backup computer and I have set it up so that I can do nearly everything my desktop can do, including wireless printing, web, email, LibreOffice suite (writer, calc, impress), PDFs, jpg editing, mp3 of music and podcasts, password manager, etc etc. A desktop replacement is my goal. There are two main obstacles at this point to fully replicating my current desktop functionality:



3 years ago Christopher Barnatt of Explaining Computers did a YT video of how he fared using a Raspberry Pi 2 as his only computer for a week. Caution: some of the specifics of what Raspbian and the Pi can and can't do is outdated (it's much more capable now, since the release of the 3B and 3B+, see: https://en.wikipedia.org/wiki/Raspberry_Pi#Specifications (https://en.wikipedia.org/wiki/Raspberry_Pi#Specifications)) but the general takeaway is that he got along just fine.

So anyway that's what I'm doing with it. I have taken it when traveling and hooked it up via HDMI to a hotel TV as a monitor and used it as a regular computer. I've set it up as a streaming media player. I've brought it to a meeting at which I gave a presentation, and ran the presentation slideshow from the pi (unbeknownst to the audience, until the end).

It's also my only computer that is not at risk of the Spectre and Meltdown vulnerabilities (which is becoming a whole class of vulnerabilities), since its chip does not use speculative execution. So that's something in its favor. It's a true general purpose computer that YOU control, rather than one that phones home with telemetry, updates on its own and sometimes breaks stuff or removes functionality, etc etc. It's your job to get under the hood and figure out how to make it do what you want it to do.

And frankly, IMO they're doing a lot of good in the educational world, and I'd probably buy one even if I had nothing to do with it. But I'd love for it to be my desktop replacement someday, and an older Pi will be my backup. Whether I can live within its limitations is an open question, but I would like for it to work out. It's the computer equivalent of a Tiny House.
Title: Re: U.K. Pi(e)s
Post by: PANTS! on April 25, 2019, 12:43:26 PM
What do you use as the browser for the Pi?
Title: Re: U.K. Pi(e)s
Post by: BAWRFRS on April 25, 2019, 02:42:01 PM
Chromium, the open-source version of Chrome.

In my experience, the Pi could not run Firefox as well as I'd like, but that would have been my preference.

Web browsing has become very resource hungry ... it's tough on the Pi. With Chromium, it's quite acceptable. Not quite as much with FF.

I do wonder if there were mobile versions of web pages that the Pi would access by default; I think FF would work better. However, it's my (very loose and uncertain) understanding that where there is a mobile version, web pages serve up based on your monitor/display size, not your processor, vram, or other characteristics.
Title: Re: U.K. Pi(e)s
Post by: BAWRFRS on April 27, 2019, 07:54:58 AM
Just finished going through and enjoying the tech.jpg thread. The most recent post is apropos to my comment about how the resources demanded by today's ad-bloated web have more than kept up with advances in processing power. Although it strikes me as hyperbole, the more general point is definitely on the mark.

(https://i.redd.it/3ccte1w6w9y11.png)
Title: Re: Raspberry Pi
Post by: Captain Video on June 24, 2019, 06:29:30 PM
I changed the thread title to Raspberry pi

The Pi 4 is out this week and it looks sweet!

https://www.raspberrypi.org/products/raspberry-pi-4-model-b/specifications/

Quote
Specifications
Broadcom BCM2711, Quad core Cortex-A72 (ARM v8) 64-bit SoC @ 1.5GHz
1GB, 2GB or 4GB LPDDR4-2400 SDRAM (depending on model)
2.4 GHz and 5.0 GHz IEEE 802.11ac wireless, Bluetooth 5.0, BLE
Gigabit Ethernet
2 USB 3.0 ports; 2 USB 2.0 ports.
Raspberry Pi standard 40 pin GPIO header (fully backwards compatible with previous boards)
2 × micro-HDMI ports (up to 4kp60 supported)
2-lane MIPI DSI display port
2-lane MIPI CSI camera port
4-pole stereo audio and composite video port
H.265 (4kp60 decode), H264 (1080p60 decode, 1080p30 encode)
OpenGL ES 3.0 graphics
Micro-SD card slot for loading operating system and data storage
5V DC via USB-C connector (minimum 3A*)
5V DC via GPIO header (minimum 3A*)
Power over Ethernet (PoE) enabled (requires separate PoE HAT)
Operating temperature: 0 – 50 degrees C ambient
* A good quality 2.5A power supply can be used if downstream USB peripherals consume less than 500mA in total.

Benchmarks and review

https://www.tomshardware.com/reviews/raspberry-pi-4-b,6193.html

Quote
The most important new features are the faster processor and GPU, more and faster RAM, the addition of USB 3 ports, dual micro HDMI ports instead of a single HDMI connection and support for 4K output. The higher bus speed that enables USB 3 support also allows the  on-board Ethernet port to support true Gigabit connections (125 MBps) where the last-gen models had a theoretical maximum of just 41 MBps. The microSD card slot is also twice as fast, offering a theoretical maximum of 50 MBps versus 25 MBps on the 3B+.

Because the new SoC needs more power, the Raspberry Pi 4 B charges over USB Type-C instead of micro USB. It also requires a power adapter that can deliver at least 3 amps of power and 5 volts, though you may be able to get away with 2.5 amps if you don’t attach many peripherals to the USB ports. Putting aside the power needs, USB Type-C connectors are reversible, which makes them much easier for kids (and adults) to plug in.

Im very excited about this, duel monitors will save me a ton of money and time.  Im not thrilled with the power requirements and the new plugs but I will get over it.
Title: Re: Raspberry Pi
Post by: PANTS! on June 24, 2019, 06:35:36 PM
I think I will get one and set up Kinja on my way to going cable free.
Title: Re: Raspberry Pi
Post by: brilligtove on June 24, 2019, 10:23:58 PM
I've been thrilled that these exist for ages, but so far never had a reason to get one. Those are some pretty impressive specs, though. Now I just need a reason...
Title: Re: Raspberry Pi
Post by: BAWRFRS on June 25, 2019, 11:24:38 AM
I've been thrilled that these exist for ages, but so far never had a reason to get one. Those are some pretty impressive specs, though. Now I just need a reason...

For me, it's:

- a tool for learning Linux
- a backup (tertiary) computer, with the possibility of future promotion
- a guest computer
- a more secure* computer

* through the 3B+ model, it is not vulnerable to the class of side-channel attacks known as Spectre / Meltdown, due to the chips' eschewing of speculative execution. It's unclear to me if this design constraint was kept in model 4 B.

I'm looking forward to hearing more about the design choices that led to the 4 B. For instance, the move to dual micro-HDMI inputs. I'm not crazy about all the cables going in and out of the box, and this just adds two more dongle adapters. However, I do get that some HDMI cables are so stiff that not only can they cause the Pi to not sit flat on a table, it actually causes stress on the board where the input port is. So if there was a little lead that was more flexible, the Pi might sit more level and without as much torquing stress.

It's my understanding that USB boot (which could be done, somewhat, with the 3B/3B+) is not yet functional on the 4B, but will be, in time, with updates. For now, it must boot by microSD card, which, for all its issues, is a less-cluttered solution. On the 3B/3B+, boot from HDD was not very reliable ... few of them spin up in time, even with a boot delay. Using a SATA external enclosure didn't help in my case either - I had hoped to spin it up and then start the Pi, but it didn't really spin up until the Pi was started too. Boot from USB flash drive works fine, but has similar shortcomings to the microSD card - namely, i/o speed and wear issues. It would be nice if the 4B could, eventually, boot straight from say an external HDD that is connected via USB 3.0. Some folks have figured out how to boot from microSD but put root on external SSD or HDD, but the threads I've followed suggest to me it's rather complicated and not reliable (in the sense that what works for one person works for another). It seems that there could also be an issue of updating / upgrading when you have a boot process customized like that. You might have to re-customize with every update, IDK. I try to keep to setups that are replicable (i.e., tweaks that work regardless of your HDD model or cable type or whatever) and easy to maintain (don't have to re-do work - like say CUPS installation or edits to config file - with each update).
Title: Re: Raspberry Pi
Post by: The Latinist on June 25, 2019, 02:45:55 PM
I intend to get a 4 GB model and set it up with ChromiumOS (an open-source implementation of ChromeOS) and an old LCD for my kids to use at home.  My daughter starts in a 1:1 Chromebook classroom this fall, so it will give her a chance to practice her skills on something familiar without breaking the bank.
Title: Re: Raspberry Pi
Post by: BAWRFRS on July 06, 2019, 10:22:28 AM
I intend to get a 4 GB model and set it up with ChromiumOS (an open-source implementation of ChromeOS) and an old LCD for my kids to use at home.  My daughter starts in a 1:1 Chromebook classroom this fall, so it will give her a chance to practice her skills on something familiar without breaking the bank.

Just curious if you got one, The Latinist.

I am still waiting in the wings; no rush ... it's still just a backup computer for me. Other than the things I mentioned above, one issue that seems to be coming up with some regularity is the much higher heat it generates. The difference in thermal images are pretty dramatic, and early tests indicate that it's easy to end up with a lot of throttling of the CPU to keep temps below a certain level (80C ?). There has been a firmware update that helps to a minor extent (lowers it 3-5C, IIRC), but it seems that the kinks are still being worked out. Hard to believe the thing might need a heat sink or fan. Probably not for light use, but given that they advertise lower-end desktop performance, well, that may come with greater heat dissipation needs.

At some point it seems you're asking too much of the thing - if you need desktop performance, get a real desktop with all the powerful hardware (and better cooling). You can always throw RPD (Raspberry Pi Desktop OS) on it if you want to stay in that UI. Part of the appeal of the Pi to me is learning how much you actually can do with such a little inexpensive thing. But it still has limits and compromises. You have to be willing to accept those, or acknowledge that it's not the right computer for your needs.
Title: Re: Raspberry Pi
Post by: The Latinist on July 06, 2019, 11:34:14 AM
I have not pulled the trigger, yet. I’ve been watching the news and reviews, too, and while it looks good on paper I’m not yet convinced they’ve found the best compromise. True gigabit Ethernet on a dedicated bus is good, as is USB3, hardware video decoding and the availability of increased RAM.  But the increased power consumption and elimination of the full-sized HDMI are negatives. And the continued reliance on SD cards for storage and boot make that now the weakest point of the board.

I have a small aluminum heatsink on my 3B+ already. As long as it doesn’t require a fan, that’s okay with me.
Title: Re: Raspberry Pi
Post by: BAWRFRS on July 06, 2019, 12:22:23 PM
I have not pulled the trigger, yet. I’ve been watching the news and reviews, too, and while it looks good on paper I’m not yet convinced they’ve found the best compromise. True gigabit Ethernet on a dedicated bus is good, as is USB3, hardware video decoding and the availability of increased RAM.  But the increased power consumption and elimination of the full-sized HDMI are negatives. And the continued reliance on SD cards for storage and boot make that now the weakest point of the board.

I have a small aluminum heatsink on my 3B+ already. As long as it doesn’t require a fan, that’s okay with me.

I agree with you in part. I have a couple tiny heatsinks on my 3B, but not my 3B+. Both are in official cases, and I try to take off the top when I run them (more important on the 3B than on the 3B+). But yeah, it seems to me that if passive cooling isn't doing enough, you probably should be considering a totally different form factor (and/or maybe you're trying to do too much and the Pi isn't the right tool).

And while I agree that the SD card has been a weak point, the SD card is a highly compact, low power draw, and neat solution. And the A1 rated cards are quite a bit better than prior types at things like random i/o speed. Obviously nothing will beat an SSD or HDD in that regard, but then you lose the elegance factor. I was going to say that if you had to have a fan and hook up SSD or HDD, then maybe the current form factor is something they should yield on ... something like the Mac Mini form factor might be more appropriate. But there are those who use Pi in embedded systems and the small form factor is valuable to them. To those of us who is it as an ersatz desktop PC, nothing of value would be lost if it increased in size from a deck of cards to a trade paperback book.

I'll concede too - I like USB boot, and in fact, have thumb drives that are clones of my microSD cards. Those don't add much clutter, of course. I've also experimented with attaching external HDD as storage and even booting from those (inconsistent results, even with powered drives).

For a long time they were insistent that they were as firm on the $35 price tag as anything in their design. But they have blinked on that a bit by offering the 2GB version at $45 surcharge and 4GB at $55. If they are really gunning for lower-end desktop performance, they may be wise to reconsider  the form factor on their "top of the line" model. It's not meant to be a mobile solution ... and a desktop user (e.g., kid learning to code) doesn't need it to be tiny.* Allowing the next Pi to be the size of a trade paperback book or something similar might open up some design alternatives that could solve some of these issues with temperature and (reliable/fast/persistent) storage, while keeping the price low.

They are really pushing what can be accomplished at that price and in that form factor. They always have, but it seems that the current design is really bumping up against practical limits. The ad-crazy modern web makes it all the more difficult. That's a monster whose appetite for system resources is never sated. I suspect that in most cases, the need for a lot of the speed, increased RAM, and so forth is because of how difficult the browsing experience is otherwise. But the browser is a pretty indispensable piece of software, even for kids learning coding.

*An upgraded Pi Zero W/WH could serve the embedded market.]
Title: Re: Raspberry Pi
Post by: BilLumberg on July 09, 2019, 11:50:30 AM
I set up a 3 B+ this weekend as a NAS using openmediavault. Very easy to set up and so far is working nicely. Only using it for music files at the moment, but plan on trying out HD video this weekend. I will also measure the power consumption. If everything works well it will replace a older PC that was using between 300-350 watts per hour to host most of my media. One nice thing is I was able to use the same network name for the pi and the shares as the old PC so all my playlists still work.

One thing I like about the SD card is it is so easy to switch what the pi is used for. The one I set up as a NAS was being used as a retropie. Swap out the card, now it is a NAS. Pop the other card in and it's back to a retropie.

Looking forward to what the pi 4 will be capable of.
 
Title: Re: Raspberry Pi
Post by: BAWRFRS on July 09, 2019, 12:19:32 PM
I set up a 3 B+ this weekend [...] plan on trying out HD video this weekend.
...
Looking forward to what the pi 4 will be capable of.

In my experience the 3B and 3B+ streamed HD video well under LibreElec. However, I am still pretty old school when it comes to video, so I don't quite see a need for a media center experience for me. We either stream Netflix (on Roku or DS's old Xbox), or we play DVDs (Redbox, or our own collection) directly into the TV. We even still have boxes of VHS tapes and a player or two that can still play them. Can't think of how a Pi-based media center would be of value to us.

Youtube never streamed well on the Pi except at Standard Def, and even then, you might still experience fits and starts (playing haltingly - much more common occurrence at 720p than 480p, but both can be affected). Not sure it's any better on the Pi 4 ... unclear to me what the issue is but I think I've read about issues w/ hardware acceleration, encoding, and so forth. I suspect that an HD stream that wasn't larded up with DRM stuff would play just fine, but that's just a hunch.

You make a good point about the ease with which you can swap out OS due to its use of microSD cards. Although that's not something that would be useful to me, I can see it being a super helpful feature for others.

I'm old enough to remember that the symptom of a computer being too slow was that you could out-type it. These days, for the typical user, speed issues reveal themselves in loading web pages and playing video (esp. YT video).  It's not lost on me that the latter relates to consuming content (bloated & advertising-supported), rather than creating it.

Title: Re: Raspberry Pi
Post by: The Latinist on July 09, 2019, 01:01:23 PM
The streaming issue with YouTube is that Chromium does not support hardware acceleration of video decoding on the Linux.  So even though the graphics processor is capable of it, it’s all being handled by the CPU. That said, even VLC on the RPi4 seems not to be able to take advantage of the hardware decoding for local videos.  I expect that to change, though support it’s unlikely to come to Chromium.

I did read a while back about Ubuntu trying to enable hardware decoding in a Chromium snap based on a patch developed by the Fedora.  I don’t know if anything came or it. Of course Raspbian isn’t snappy; is Ubuntu MATE yet?
Title: Re: Raspberry Pi
Post by: Captain Video on July 09, 2019, 02:49:56 PM
I have not been keeping up.

VLC on the Pi would certainly make my life easier.

Has anyone seen 2 different videos playing at the same time on duel screens yet?  I can always split them across a 3840 x 1080 comp and stretch across both screens but 2 independent videos would be ideal.

Title: Re: Raspberry Pi
Post by: The Latinist on July 09, 2019, 03:59:51 PM
I doubt that it could handle two full-screen HD videos until the hardware decoder is working.  From what I’ve seen, it’s not perfect even with one video at 1080p.
Title: Re: Raspberry Pi
Post by: Captain Video on July 09, 2019, 04:09:32 PM
is the hardware decoder not working with OMXplayer?

Title: Re: Raspberry Pi
Post by: The Latinist on July 09, 2019, 07:23:30 PM
is the hardware decoder not working with OMXplayer?

I don’t know.  I don’t have a Pi4, and the reviews I saw which demonstrated video playback on it only tested Chromium/YouTube and VLC. This is a new chipset, though, so I wouldn’t be surprised if driver support is not yet implemented.
Title: Re: Raspberry Pi
Post by: Captain Video on July 09, 2019, 08:02:03 PM
yea microcenter got them in the store but sold out before I had time to get one, As soon as the next shipment comes in I'm grabbing one to test with.
Title: Re: Raspberry Pi
Post by: stands2reason on July 09, 2019, 09:59:47 PM
using between 300-350 watts per hour

I think you mean watt-hours per hour, or just watts.
Title: Re: Raspberry Pi
Post by: BilLumberg on July 10, 2019, 11:25:36 AM
Yeah, just watts. Those old computers can really use some power. The 300-350 was sitting idle with just the PC and UPS with no monitor. Recently purchased a kill a watt meter and it's kind of fun seeing how much simply updating to newer tech can save electricity.

Going to try a little 5000maH power pack that has pass-through charging as a UPS for the NAS pi so I wont need to hook up a monitor to log in every time the power blips. There is probably some way to do it through the network, but I have not looked into that yet.
Title: Re: Raspberry Pi
Post by: stands2reason on July 10, 2019, 03:44:01 PM
My gaming laptop has a quad-core i5 and 1050Ti( both 2017, 14nm). The power adapter is rated for 120W. The TDP of the CPU & GPU is about 2/3 of that. When you consider computation per watt-hour, transistor size is a big deal. My MacBook (also 14nm silicon) could use as little as 5 W when idle.
Title: Re: Raspberry Pi
Post by: The Latinist on July 16, 2019, 02:42:14 PM
Be aware that there is a fundamental flaw with the RPi 4’s USB-C power sink implementation; they shorted two pins which must remain isolated. It seems to have been an effort to save one resistor by running both pins into one.  The result is that the RPi 4 cannot be charged with any ‘e-marked’ power adapters (those that contain active circuitry to determine the type of device attached).  That includes most higher-end adapters including the one that comes with USB-C MacBooks.  It may be several months before they can get a revision out.
Title: Re: Raspberry Pi
Post by: brilligtove on July 16, 2019, 02:52:44 PM
Is that short something you can break?
Title: Re: Raspberry Pi
Post by: Captain Video on July 16, 2019, 02:55:07 PM
good to know

only use an official Raspberry Pi 4 power cable, check

Title: Re: Raspberry Pi
Post by: The Latinist on July 16, 2019, 03:04:19 PM
Is that short something you can break? The

No, they've combined the two leads on the PCB and run them into the same 5.1kΩ resistor. I don't see how you could fix that.

More details: https://medium.com/@leung.benson/how-to-design-a-proper-usb-c-power-sink-hint-not-the-way-raspberry-pi-4-did-it-f470d7a5910

Quote
Instead of trying to come up with some clever circuit, hardware designers should simply copy the figure from the USB-C Spec exactly. The Figure 4–9 I posted above isn’t simply a rough guideline of one way of making a USB-C receptacle. It’s actually normative, meaning mandatory, required by the spec in order to call your system a compliant USB-C power sink. Just copy it.

good to know

only use an official Raspberry Pi 4 power cable, check

You should be able to use most 3A phone chargers, which are usually not e-marked.  But, yes, the official charger is guaranteed to work.
Title: Re: Raspberry Pi
Post by: Captain Video on July 16, 2019, 03:22:03 PM
I just checked and Microcenter finally has a bunch of the 1gb units in stock today. If they are still there tomorrow I can pick one up.  I wish they had some 4s.
Title: Re: Raspberry Pi
Post by: brilligtove on July 16, 2019, 03:31:02 PM
Is that short something you can break? The

No, they've combined the two leads on the PCB and run them into the same 5.1kΩ resistor. I don't see how you could fix that.

More details: https://medium.com/@leung.benson/how-to-design-a-proper-usb-c-power-sink-hint-not-the-way-raspberry-pi-4-did-it-f470d7a5910

Quote
Instead of trying to come up with some clever circuit, hardware designers should simply copy the figure from the USB-C Spec exactly. The Figure 4–9 I posted above isn’t simply a rough guideline of one way of making a USB-C receptacle. It’s actually normative, meaning mandatory, required by the spec in order to call your system a compliant USB-C power sink. Just copy it.

good to know

only use an official Raspberry Pi 4 power cable, check

You should be able to use most 3A phone chargers, which are usually not e-marked.  But, yes, the official charger is guaranteed to work.
Ah. Not a blob of solder at the pins, then. :)
Title: Re: Raspberry Pi
Post by: The Latinist on July 16, 2019, 07:23:55 PM
Yeah, the traces are printed that way.

It appears they were just trying to save money by eliminating  what they thought was a superfluous resistor. To be fair, part of their core mission is making the board affordable; but I heard the component only costs about 1/20¢, which means they’d save about $500 on a run of 1 million boards. Now they’re looking at bad PR and the cost of a redesign.  Penny wise and pound foolish, as they say.

I’m actually a bit more concerned about the heat issues; the new processor seems to be generating a lot of heat (and drawing significantly more power) under load. I don’t mind putting a heat sink on one, but I’m not willing to put a fan on it.  Perhaps for some use cases it could be under-clocked.
Title: Re: Raspberry Pi
Post by: BAWRFRS on July 21, 2019, 11:42:16 AM
I’m actually a bit more concerned about the heat issues; the new processor seems to be generating a lot of heat (and drawing significantly more power) under load. I don’t mind putting a heat sink on one, but I’m not willing to put a fan on it.  Perhaps for some use cases it could be under-clocked.

I share your concern. I too would prefer to just add a heat sink, as I did for my 3B model (it came with two, in a Canakit, uh, kit). That said, I don't run my 3B with the top on its case. I keep it open during use.

I'm content to wait out the re-emergence of USB Boot and any other stuff that isn't quite operational out of the box. But the heat thing is not (much) solved by software/firmware updates. There is one that'll give you 3-5C reduction but if you're already at 81C, that's not quite enough to avoid throttling, I think!

FWIW, based on my reading of the many experiments people have done with cooling their Pi 4, it appears that a fan is the most efficacious solution, by far. A (typical) heat sink buys you some time, but does not solve the overheating (to the point of throttling) issue, especially in an enclosed case. You have to carry that heat away somehow, and a fan is the most reliable way to do it.

Other suggestions have been to simply not use a case, to have it exposed to the air, preferably on edge so that top and bottom are both exposed, etc. But that's a most inelegant solution, and makes me feel that at some point, they're chasing desktop performance that requires desktop-style cooling. Now, why can a smartphone or tablet be all enclosed and yet not overheat? IDK. I'm pretty sure smartphones aren't cooled by fans. Is the whole smartphone enclosure a heat sink? Is a heat sink that large sufficient, as opposed to those tiny ones Canakit provided me?

My (aging, thick) laptop has some tiny fans inside and they certainly blow out some heat. IDK how today's super-thin laptops vent heat; I suspect the case is a giant heat sink. But I can't help but wonder if the RPF is at a design crossroads. Something will have to give ... price or speed. They shouldn't need such speed to teach programming, but to the extend that any of that programming has to interface with a browser, modern web browsing is absurdly resource intensive. And with that speed/power comes the need to vent heat: fans or heat sink, liquid cooling, etc.
Title: Re: Raspberry Pi
Post by: mindme on July 22, 2019, 10:08:51 AM
Building out my own retropie bartop.


(https://i.imgur.com/K3PgVjH.jpg)
(https://i.imgur.com/Z20pWZJ.jpg)
(https://i.imgur.com/omLN7wl.jpg)
(https://i.imgur.com/Gxl12Fv.jpg)



Title: Re: Raspberry Pi
Post by: BAWRFRS on July 22, 2019, 02:49:39 PM
Chris Barnatt at Explaining Computers with another great video ... in this one, he comes down squarely on the necessity of active cooling for the Pi.

https://youtu.be/AVfvhEJ9XD0 (https://youtu.be/AVfvhEJ9XD0)

A couple of caveats:

It seems to me that his tests demonstrate the necessity of active cooling to keep temperatures well below throttling level. However, it does not appear he demonstrated the necessity of active cooling as far as performance goes. Even a small heatsink, coupled with no Pi 4 case, ran the prime number task about as fast as with an actively cooling fan. It just did so at a much hotter (82C) temperature than the Pi did with a fan + heatsink (55C).

This leads to another issue - he didn't test the performance under the simple condition of no heatsink and no case. Might have it done the task as quickly, and at around 82C, simply by removing the case?

That said, the ability to run at lower temps could reasonably imply longer service life for the Pi.

For me, I'd not likely run the Pi 4 without some sort of enclosure. It would scratch up my wooden desktop surfaces and possibly get too hot to touch, unless I could figure out a way to mount it cleverly. I suspect a well-vented, fan-enabled case will prove a necessity.
Title: Re: Raspberry Pi
Post by: Captain Video on July 22, 2019, 04:13:03 PM
Yea if i have to put fans on them some sound guy will see it and then they will suddenly hear it (inside joke) No fans.  Im thinking a big heat sink and a case designed to allow airflow or a metal case with a heatsink built in. I will already need to design something to hold two of those mini HDMI plugs in place with strain relief. 

I still haven found time to drop by microcenter.  >:(
Title: Re: Raspberry Pi
Post by: The Latinist on July 22, 2019, 04:47:23 PM
My takeaway from his tests was that a well-ventilated case with a heat sink should be sufficient. Although he was able to get it significantly cooler with a fan, it was not significantly faster than with the heat sink alone, indicating that most of the throttling gains come from keeping it under about 82°C.  If you look at his numbers, his video encoding test took 41 minutes @90°C with no heat sink in the official case, 11 minutes @81°C with a tiny heat sink and the top off of the case, and 10 minutes @56°C with a huge heat sink, fan and custom case.
Title: Re: Raspberry Pi
Post by: The Latinist on July 26, 2019, 09:53:50 AM
Now that I have a 4K TV, I kind of want to get a RPi 4 to try it out on.
Title: Re: Raspberry Pi
Post by: BAWRFRS on July 29, 2019, 09:39:08 PM
Now that I have a 4K TV, I kind of want to get a RPi 4 to try it out on.

You probably know this, but just in case (or for other readers) -

I suspect there's a difference between being able to play a 4k video file in a given format from local storage (e.g., via USB 3 flash or SSD), and being able to watch a video from Youtube or some other streaming service in 4k. Not just from potential speed difference between internet connection and flash memory read, but also things like hardware acceleration, encoding, etc etc. A similar reasoning, I think, with why the Pi 3 model(s) can play 1080p video, but only via an OS like LibreElec, not via a browser window in Raspbian.

That said, I wish you success, and look forward to hearing how it turns out.
Title: Re: Raspberry Pi
Post by: BilLumberg on July 31, 2019, 06:31:18 PM
Update on the raspberry pi NAS. The pi and two external drives (1TB, and 5TB) only pull 10 watts at idle, and 20 when streaming from both drives simultaneously. Big drop from the 300 watts at idle it replaced. I was overthinking the openmediavault login. All that is needed is the IP address and then everything is done through the browser interface. I initially thought it needed to be logged in directly to start it. So far everything has worked flawlessly. Which has been my experience with most linux based systems. They just work. The best part is I was able to do this with hardware I already had. Of course most thanks go to the people who put in the work developing the openmediavault software.

Now I think I will see how well a pi-hole works for network ad blocking. After all, I have a extra micro sd card just sitting there doing nothing.
Title: Re: Raspberry Pi
Post by: The Latinist on August 06, 2019, 03:16:43 PM
I’ve seen really good reviews of the Flirc case (https://flirc.tv/more/raspberry-pi-4-case). The case is aluminum and the whole thing acts as a heat sink. It gives access to all of the connectors with the exception of the GPIO (though it does provide room for a ribbon cable).  Tests I saw indicated it can keep the maxed-out CPU temp at 60°F with no fan.

The only draw-back seems to be reduced Wi-Fi and Bluetooth range (for obvious reasons).
Title: Re: Raspberry Pi
Post by: Captain Video on September 06, 2019, 04:37:55 PM
I was finally able to purchase a Pi 4 for an upcoming project.

I got the 2gb version and an official Pi power supply.

Unfortunately I completely spaced the new micro HDMI ports and for some reason I was thinking they were minis. I have tons of mini adapters and not one micro. My choice today, drive an hour through Atlanta traffic each way, order online and wait a few days, pay $19 for one at Walmart. UGGGGG! Walmart won but I only purchased 1 unit, the duel monitor test will have to wait.

I'm in the middle of a noobs install now for my first attempt. Ill try something more challenging after I mess around with this for a while. I'm already having issues. Either the crappy Walmart dongle is faulty or its putting out an improper resolution for the monitor or the board is faulty. After unplugging and trying both ports several times I managed to get a noobs install screen in a crappy resolution, not sure which one.

It seemed to go through its install just fine but after reboot I have go lights and a black screen again. I have been fiddling with it trying unplugging and changing ports as before but no luck this time.  I mite move to another room and try it on a TV, I want to believe its the Walmart piece of shit $19 dongle but maybe a different EDID signal will fix it.  The board did not come in an anti-static bag but the box seemed sealed. It mite have been a bad one or a return placed back on the shelf.  I don't want to drive to the other side of town today but may have too.
Title: Re: Raspberry Pi
Post by: The Latinist on September 06, 2019, 05:00:36 PM
Yeah, the choice of micro HDMI is a disappointing one.  It increased functionality for those who need two monitors, but it made it harder and more expensive for those who don't to get started; almost everyone has an HDMI cable, but I had never even heard of micro HDMI before this.
Title: Re: Raspberry Pi
Post by: BAWRFRS on September 23, 2019, 11:25:41 AM

I'm in the middle of a noobs install now for my first attempt. Ill try something more challenging after I mess around with this for a while. I'm already having issues. Either the crappy Walmart dongle is faulty or its putting out an improper resolution for the monitor or the board is faulty. After unplugging and trying both ports several times I managed to get a noobs install screen in a crappy resolution, not sure which one.

It seemed to go through its install just fine but after reboot I have go lights and a black screen again. I have been fiddling with it trying unplugging and changing ports as before but no luck this time.  I mite move to another room and try it on a TV, I want to believe its the Walmart piece of shit $19 dongle but maybe a different EDID signal will fix it.  The board did not come in an anti-static bag but the box seemed sealed. It mite have been a bad one or a return placed back on the shelf.  I don't want to drive to the other side of town today but may have too.

Before you assume it's the board issue, or even the dongle, you might want to try a straight Raspbian install. I'm not a fan of NOOBS, though that's how I started out. IIRC, for me the issue was the complication of updates. I was just using the bootloader to choose between LibreElec and Raspbian. Before long, I realized that I didn't have a need or desire for a media center, and would not likely use LibreElec. Granted, it was THE way to stream HD smoothly out of the Pi. But it still wasn't, for me, a practical solution to watching HD video, since LibreElec didn't offer any other desktop applications. I would almost always be searching and watching videos from the context of everyday desktop computer use, and I didn't want to have to reboot into another OS to switch back (say to writing a document, email, or whatever). I'd have just left it as-is, and just booted into Raspbian alone, but I think update/upgrade didn't work quite the same under NOOBS as straight Raspbian, and that messed me up or stalled me in some way. I can't recall exactly, but in the end, I ditched NOOBS and went to a Raspbian-only card.

Good luck.
Title: Re: Raspberry Pi
Post by: Captain Video on September 23, 2019, 12:02:09 PM

I'm in the middle of a noobs install now for my first attempt. Ill try something more challenging after I mess around with this for a while. I'm already having issues. Either the crappy Walmart dongle is faulty or its putting out an improper resolution for the monitor or the board is faulty. After unplugging and trying both ports several times I managed to get a noobs install screen in a crappy resolution, not sure which one.

It seemed to go through its install just fine but after reboot I have go lights and a black screen again. I have been fiddling with it trying unplugging and changing ports as before but no luck this time.  I mite move to another room and try it on a TV, I want to believe its the Walmart piece of shit $19 dongle but maybe a different EDID signal will fix it.  The board did not come in an anti-static bag but the box seemed sealed. It mite have been a bad one or a return placed back on the shelf.  I don't want to drive to the other side of town today but may have too.

Before you assume it's the board issue, or even the dongle, you might want to try a straight Raspbian install. I'm not a fan of NOOBS, though that's how I started out. IIRC, for me the issue was the complication of updates. I was just using the bootloader to choose between LibreElec and Raspbian. Before long, I realized that I didn't have a need or desire for a media center, and would not likely use LibreElec. Granted, it was THE way to stream HD smoothly out of the Pi. But it still wasn't, for me, a practical solution to watching HD video, since LibreElec didn't offer any other desktop applications. I would almost always be searching and watching videos from the context of everyday desktop computer use, and I didn't want to have to reboot into another OS to switch back (say to writing a document, email, or whatever). I'd have just left it as-is, and just booted into Raspbian alone, but I think update/upgrade didn't work quite the same under NOOBS as straight Raspbian, and that messed me up or stalled me in some way. I can't recall exactly, but in the end, I ditched NOOBS and went to a Raspbian-only card.

Good luck.

Thank you

It turned out to be an EDID pass-through issue with the micro HDMI dongle I was using. I purchased another one and now have a 1080p signal. Unfortunately the dongle is too wide to allow 2 to be used at the same time, this is going to be an issue and I wish they had designed this differently. Microcenter had no cables just the dongles, they actually had a Monster brand that cost more than the basic Pi itself at $38 (fuck Monster) Best buy had a thin 4 ft cable rated for 1080p only at $45, no thanks. I just need to settle on Amazon Markertek or New egg I guess. I hate that, what if I need a cable asap for work? then i'm screwed.

Micro HDMI sucks

I did a quick video test but VLC still goes goes dark when going full screen. it might be trying to fullscreen to the second screen I don't have hooked up and I have not spent the time to investigate why yet. When I do have some time I will install raspbian without noobs as well as LibreElec and a few other things I want to test.

this guy managed to get video on two screens with his kiosk software.

https://community.infobeamer.com/t/raspberry-pi-4-release-and-info-beamer-information/565/12

Quote
It seems that right now the Pi4 software doesn’t allow hotplugging of displays. It sounds like the displays are only detected when the Pi boots. This might make reliable installations using dual displays difficult, if the screens are not guaranteed to be turned on when the Pi starts. If a screen is not detected at boot, info-beamer (and I’m pretty sure any other Pi based solution) won’t be able to detect the screen later once it gets turned on). As a result, I’m not yet sure how practical the dual screen mode will be. We’ll see.

Right now only GL content can be shown across dual screens. Videos of any kind won’t work as of now.

that last bit probably relates to my fullscreen issue with VLC

Quote
4K / H265 video playback proof of concept
This is another important milestone on using the Pi4’s full potential: My in-dev version of info-beamer pi can now play 4K videos encoded in the H265/HEVC format for the first time. As it’s getting integrated into the normal info-beamer video runtime, splitting a video like this across two screens also works:

Quote
Quick status update. The core video player component has been rewritten to be more generic. It can now decode H264 into GL textures, H264 into fullscreen over/underlays as well as HEVC (so 4K videos!) into over/underlays. See this screenshot:
Title: Re: Raspberry Pi
Post by: BAWRFRS on September 23, 2019, 12:27:25 PM
I hear you on the dongles - unfortunate that such things are needed when the right cable isn't easy to find. I thought that RPT was offering them at a pretty reasonable cost, but maybe their resellers aren't stocking them much (yet). IDK. I think they come in the all-in-one kits, but obviously some of us are going to want to buy them a la carte, say if we already have a keyboard/mouse to use - or don't want the case.

One potential good thing about the official dongles, besides the ability to use both ports, is that they might mitigate the torque often put on the board by a cable that doesn't happen to lay in exactly the right orientation to the port. This is especially a problem if the cable is thick or considered heavy duty. This can lead to the Pi not laying flat on whatever surface you have it sitting on. Like a shock absorber, the dongle might serve as a kind of "twist absorber" in such cases.

FWIW I have had good luck with Amazon Basics HDMI cables, but YMMV.