Designing Raspberry Pi 400(raspberrypi.org)
raspberrypi.org
Designing Raspberry Pi 400
https://www.raspberrypi.org/blog/designing-raspberry-pi-400/
134 comments
My biggest disappointment is that they did not put enough effort into designing a PCB except to "unfold" the existing RPI4 one. The biggest drawback is the micro-HDMI ports instead of the full size one. Even with space constrains a lot of people would prefer one full-size HDMI port instead of 2 micro. My other wishes are compute module, M2 socket and RTC on the board, but obliously driving cost down prevented this.
There's only two things I dislike on the Pi 4 today really.
No options for fast internal storage, and that tiny HDMI port. Given Pi 4 has reasonable CPU and up to 8GB of RAM, the former is a shame. The full size HDMI port on Pi 3 was compatible with cables virtually everyone already owned.
A model in the range with 32 or 64gb fast storage on board would be great - The Pi is useless for many without purchasing an additional SD card for a boot volume anyway!
No options for fast internal storage, and that tiny HDMI port. Given Pi 4 has reasonable CPU and up to 8GB of RAM, the former is a shame. The full size HDMI port on Pi 3 was compatible with cables virtually everyone already owned.
A model in the range with 32 or 64gb fast storage on board would be great - The Pi is useless for many without purchasing an additional SD card for a boot volume anyway!
IIRC, The internal storage thing is a limitation of the system-on-chip they use. They only have access to a single pci lane, so they decided it's better for the form factor and education use-case to connect the lane to a hardwired pair of usb3 ports than a potentially more flexible pci-e port, which would allow nvme storage.
FWIW, the new compute module does have built-in access to the pci lane, which gives you the option to use nvme in addition to the onboard flash storage.
FWIW, the new compute module does have built-in access to the pci lane, which gives you the option to use nvme in addition to the onboard flash storage.
they've got compute modules with emmc, and and a board you can slap them on, that has full sized HDMI.
https://www.raspberrypi.org/products/compute-module-4-io-boa...
costs more, and takes up more space, but it includes a whole bunch of other goodness.
the compute module with 8gb of ram and 32gb of emmc isn't available in small quantities yet, but that should happen sooner or later.
https://www.raspberrypi.org/products/compute-module-4-io-boa...
costs more, and takes up more space, but it includes a whole bunch of other goodness.
the compute module with 8gb of ram and 32gb of emmc isn't available in small quantities yet, but that should happen sooner or later.
Am I the only one who prefers micro HDMI? I've heard good arguments to suggest it isn't very robust in the hands of kids... but from my own perspective all my micro HDMI cables are much thinner than my full-sized HDMI ones and they... just sit better. That said I've got an M.2 PCIe 2230SSD hanging out of the USB port on an adapter, so any grace or elegance is gone from my setup.
Edit: mini to micro (mini on the Pi Zero, micro on Pi 4/Pi 400)
Edit: mini to micro (mini on the Pi Zero, micro on Pi 4/Pi 400)
It would be great if a mini-HDMI to HDMI breakout board was available for purchase. It seems some people are working on it (https://easyeda.com/eddperks/RasPi4-HDMI-Breakout)
Isn't such an adapter commonly available in cable form? Full size HDMI on one end, smaller one on the other. Probably sold at a lot of electronics stores.
(One is included in the box here)
Yes, cable adapters are plentiful. There are also dongles, but the two ports are too close together to fit dongles in both ports (at least in the Raspberry Pi 4B).
You can just buy HDMI to HDMI mini cables from Monoprice for cheap and no space issues.
https://www.monoprice.com/product?p_id=3645
https://www.monoprice.com/product?p_id=3645
The real question for windows on arm users is does the pci bridge and usb controllers still have that 3GB ram ceiling issue?
It’s so lame having 5gb of ram unused in a 64bit system.
It’s so lame having 5gb of ram unused in a 64bit system.
Windows on RPi has a workaround for that via a filter driver for earlier BCM2711 steppings.
Newer BCM2711 steppings as shipped in CM4 and RPi 400 do not have the issue. (and that newer stepping could very well have reached regular RPi4s too)
Newer BCM2711 steppings as shipped in CM4 and RPi 400 do not have the issue. (and that newer stepping could very well have reached regular RPi4s too)
I'm genuinely curious why you would want to run Windows on an RPi when there's good Linux support. Why pick a proprietary OS that costs money when you have a free and open source alternative with all the drivers and lots of code examples using the GPIO ports, etc? Genuinely curious as to what your motives are.
I'm not the parent poster but Windows-on-Pi seems like it would be very useful (in terms of affordability) for testing purposes.
Either a whole swarm of them for automated testing, or perhaps just keeping one around to make sure your stuff works on Windows outside of a VM, etc.
Either a whole swarm of them for automated testing, or perhaps just keeping one around to make sure your stuff works on Windows outside of a VM, etc.
What is there to test on Windows ARM?
lack of full hdmi port is a nogo for me, maybe rpi 500 will have them
Get a short mini-hdmi to full-hdmi, and epoxy it to the rpi400.
It's a slight inconvenience, but hardly a big deal. The 400 comes with a free adapter, and if you want a cleaner solution, here's a cable for 7 bucks delivered: https://www.amazon.com/Adapter-Wenter-Action-Camera-Supporte...
Honestly, it sounds like you're just looking for an excuse to not like the 400. Especially since others have said that it comes with an adapter.
It's like saying you won't buy one because it looks too much like a Commodore 64.
It's like saying you won't buy one because it looks too much like a Commodore 64.
> Left-handed? We have already seen a few comments about the USB ports being on the left side of the unit, and the fact that this makes the mouse cable cross over for most right-handed users. The PCB shape had to be defined early on so that the industrial designers could get on with the housing design, and I then stared endlessly at the PCB layout, trying to get one of the USB ports to route to the right side without wrecking the signal integrity of the memory or the HDMI; I could not find a way to do this. Left-handed folks and Bluetooth mouse-owners will be happy at least!
Ha! I questioned this in an earlier thread (https://news.ycombinator.com/item?id=24980083)
It's really great to see a response that highlights the reasons (and an acknowledgement that it was something they truly did try to address!).
But, my comment on the promo photo layouts still stand - having the mouse on the left side just for the clean shot must have just stood out for a lot of people. They should just lampshade it - say they're satisfying the lefties for once!
Ha! I questioned this in an earlier thread (https://news.ycombinator.com/item?id=24980083)
It's really great to see a response that highlights the reasons (and an acknowledgement that it was something they truly did try to address!).
But, my comment on the promo photo layouts still stand - having the mouse on the left side just for the clean shot must have just stood out for a lot of people. They should just lampshade it - say they're satisfying the lefties for once!
As a lefty who mouses right-handed -- do many actually put their mouse on the left side? I started computing at a young age, and I suppose I didn't bother to or think to rearrange the desk so I could use the mouse left-handed. Now, trying to mouse left-handed feels like trying to write right-handed; it's taxing and aggravating to try to muster the precision required.
I am lefty who used to mouse right sided but a shoulder injury makes me favor the left now. I still use righty button mapping so coworkers can use it immediately. It doesn't take long to get used to it. The biggest annoyance is left side keyboard shortcuts aren't immediately available.
My first mouse was on an Apple IIgs and I set that up lefty on day one but parental unit dissuaded me after that.
My first mouse was on an Apple IIgs and I set that up lefty on day one but parental unit dissuaded me after that.
For a long time I was a righty that used a mouse left handed. It was just how I learned. It wasn't until I got older and fps controls changed from the numpad or arrow keys as default to wasd for movement that I eventually just switched. That and going through school and being at work with mice being on the right side.
I do, because it solved a rsi issue for me. The mouse is far closer to the centerline of my body when I don’t have the keypad in the way.
I use a ”ten-key-less” keyboard (without numerical part but with arrow and delete-block keys) for this reason.
I've had a long history with obscure keyboards. This all started in `99 with the Apple Extended Keyboard 2 (ADB, great action, but wide), then the narrower/older Apple Keyboard (adb, good action till it wore out), Two Model M13s with trackpoints (PS/2, good action, but one started having key repeat issues, and the other one has an aging cable thats tempermental.) They also don't have enough modifier keys anymore.
By the time tenkeyless boards were common, I was firmly in the lefthanded mouse camp.
For a while, I was running two mice, one for each side, but I pretty quickly ended up with just the one.
By the time tenkeyless boards were common, I was firmly in the lefthanded mouse camp.
For a while, I was running two mice, one for each side, but I pretty quickly ended up with just the one.
Same, I switched decades ago because of rsi. Now I always use the mouse on the left. I used to switch to the right only to do very fine “lasso” work in photoshop. But I do full time development only now.
Who uses a wired mouse today anyway? I haven't used one in years! I associate it with a ball even ;)
The most exciting part of the Raspberry Pi to me isn't the current hardware, but what they'll do next for $35. The different ram models in the Pi 4 are great too. As soon as we get a "Pi 500" in a future generation with the 8GB model, I think we can officially replace computers for browser-only users with one of these (especially if the graphics hardware improves for videos).
Even now, I wonder if this would be fine for someone who just uses Facebook, email, and YouTube. Maybe a bit of lag here and there, but I'd imagine this would do the trick, right?
Even now, I wonder if this would be fine for someone who just uses Facebook, email, and YouTube. Maybe a bit of lag here and there, but I'd imagine this would do the trick, right?
I've been testing out both the 8GB Pi 4 and the new Pi 400 overclocked to 2.2 GHz. For many things, both are perfectly adequate.
But the slight bit of missing performance (compared to a $300+ low-end celeron or AMD laptop) becomes apparent when you do things like make a video full screen (takes 3-10 seconds), scroll on a JS-heavy page, or have a number of apps open at the same time and switch between them while one of them is doing some heavy processing.
It's definitely tolerable and for the price the Pi is a great little computer. Also as soon as I get a few more CMs, I'm going to run some of my web stuff on them from my home since they're silent, power efficient, and adequate now unlike previous generations.
But it's not necessarily a standard more expensive desktop replacement for the majority of people yet. As it stands today I think this would be a great computer for a family, a kid learning how to type and use a computer, that sort of thing. Additionally, it would be an excellent computer for those who can't afford a $300+ laptop but already have a TV or can pick up a $40 monitor off Craigslist.
But the slight bit of missing performance (compared to a $300+ low-end celeron or AMD laptop) becomes apparent when you do things like make a video full screen (takes 3-10 seconds), scroll on a JS-heavy page, or have a number of apps open at the same time and switch between them while one of them is doing some heavy processing.
It's definitely tolerable and for the price the Pi is a great little computer. Also as soon as I get a few more CMs, I'm going to run some of my web stuff on them from my home since they're silent, power efficient, and adequate now unlike previous generations.
But it's not necessarily a standard more expensive desktop replacement for the majority of people yet. As it stands today I think this would be a great computer for a family, a kid learning how to type and use a computer, that sort of thing. Additionally, it would be an excellent computer for those who can't afford a $300+ laptop but already have a TV or can pick up a $40 monitor off Craigslist.
> I've been testing out both the 8GB Pi 4 and the new Pi 400 overclocked to 2.2 GHz. For many things, both are perfectly adequate.
I wonder if I'm doing something wrong. I have a 4GiB pi 4B and have found it laggy enough to be basically completely unsuitable for even the most lightweight interactive computing tasks, e.g. basic (ad filtered) web browsing. I think there might have been a bit of intermittent laginess in typing into an xterm in a bare bones tiling window manager with basically nothing else going on, but I'd have to check again. After the initial hickup on full-screening, did the video play back properly for you? For me it was not possible to play 480p youtube videos.
All in all this was much worse than I expected from a quad core machine with 4GiB.
Now I haven't got the fastest micro-SD card, and I'm running with Ubuntu 20.04 64bit server rather than raspian, but is this just what I should expect, or should a different configuration of the 4GiB 4B handle light web surfing and fullscreen video playback?
I wonder if I'm doing something wrong. I have a 4GiB pi 4B and have found it laggy enough to be basically completely unsuitable for even the most lightweight interactive computing tasks, e.g. basic (ad filtered) web browsing. I think there might have been a bit of intermittent laginess in typing into an xterm in a bare bones tiling window manager with basically nothing else going on, but I'd have to check again. After the initial hickup on full-screening, did the video play back properly for you? For me it was not possible to play 480p youtube videos.
All in all this was much worse than I expected from a quad core machine with 4GiB.
Now I haven't got the fastest micro-SD card, and I'm running with Ubuntu 20.04 64bit server rather than raspian, but is this just what I should expect, or should a different configuration of the 4GiB 4B handle light web surfing and fullscreen video playback?
Ive read multiple reports that the Ubuntu distrivution is significantly slower than the Raspian bundle. I dont know the root cause, but you could check out the stock image for a comparison yourself
How do you actually run compute modules (I assume that's your 'CM' abbreviation above)? Do you need a custom "rack" or something? If so, where do you get them?
Either design your own carrier board or use https://www.raspberrypi.org/products/compute-module-4-io-boa...
Bummer. I would pay good money for a single board that let me mount 4-8 of these guys. I'm aware that the Turing Pi 2 will supposedly do this, but it's still in development.
[deleted]
The CM4 is still a very new product, I know of at least a few other projects that are still on the drawing board. Give it time, I think we'll see some creative adaptations.
For now I'm just using the IO board, and I have a couple more on the way, and I'll rack them up using M2.5 spacers.
For now I'm just using the IO board, and I have a couple more on the way, and I'll rack them up using M2.5 spacers.
Can you list the other projects? What are the advantages of racking CM4s + IO boards vs racking RPI4s? Is it just the extra bit of compute power? In my mind, the biggest draw to the CMs is the prospect of putting them all on one board without having to run cables to each, especially since there aren't multiport USB-C power supplies available that can power multiple RPI4s. Another advantage is the prospect of faster SSD communication.
One of these things stand out. Making a video should take one or two frames. (Milliseconds.)
Something is very wrong with the state of software and GUI. There is nothing inherently slow about making a video full screen, but I understand there is something in todays software pipeline making this a bottleneck.
Something is very wrong with the state of software and GUI. There is nothing inherently slow about making a video full screen, but I understand there is something in todays software pipeline making this a bottleneck.
The Rpi4 plays 720p video full screen at 5% cpu usage (because it has hardware decoding support) - using omxplayer. The hard part is for the hardware decoding support to be enabled in the right places and it seems like kodi is the only place (mpv, vlc don't do it by default)
The other missing piece for the transition to fullscreen is a robust compositor API, such that the same compositional layer can just have its size changed rather than going from app-compositor to system-composited in a new window. Something like, say, Wayland. <insert that whole debate/debacle here>
It absolutely should only take a couple of frames to make a video fullscreen, but to put things into perspective, on my 2015 macbook it takes 3-4 seconds to toggle fullscreen on youtube, and my much more powerful linux desktop isn't much faster.
Have you considered that the compression algorithms for video are nontrivial? I mean I'm sure there can be dedicated hardware for video decoding, but would you put that in a low-cost, low-energy entry-level CPU where you want to shave off as much cost in favor of flexibility?
The Pi is not primarily intended for media consumption. That said, for a similar price to a RPI + display you can get a cheap tablet that will (should?) have dedicated video hardware.
The Pi is not primarily intended for media consumption. That said, for a similar price to a RPI + display you can get a cheap tablet that will (should?) have dedicated video hardware.
The original Pi CPU was intended for media consumption in set-top-boxes; it was a huge video core with a small ARM on the side.
It has had hardware video decompression for multiple revisions.
In fact it had H264 decoding in all revisions, optional unlockable MPEG2 and VC1(?) up to and including all Pi3 models and H265 since the Pi4.
The regular Pi 4 can run at 2.2 GHz? With external cooling I assume.
Pi 400 is the one with the keyboard and has built in soft-cooling. I wonder what a Raspberry Pi overclocking competition would do.
So far no matter what I've tried I can't get beyond 2200 MHz.
Look into top end GPU or CPU overclocking on the desktop side of things if you want to know where RPI overclocking would end up. It's going to be the same general thing - get it as cold as possible and ram as much power & voltage as possible as cleanly as possible. It wouldn't end up looking anything like a Raspberry Pi at the end of the day, though, as the first step would be replacing the entire power delivery system (see for example products like https://www.evga.com/articles/01140/evga-epower-v/ on the extreme GPU side of things)
Even the Raspberry Pi 400 has hardware decoding where the Raspberry Pi Foundation claims up to H.265 video decoding in 4K @ 60 fps in hardware. That sounds great for all sorts of media and streaming!
However the fine print looks to be that this may not hold true for Chrome and streaming / YouTube, but offline videos with certain players because Chromium doesn't support hardware acceleration for this API. Chromium supports VAAPI, this uses libva. sigh Why does this Linux hardware decoding story always repeat itself. :-(
Still, raw CPU may let it manage at least 1080p at 30 fps but I can't say for sure for anything more.
However the fine print looks to be that this may not hold true for Chrome and streaming / YouTube, but offline videos with certain players because Chromium doesn't support hardware acceleration for this API. Chromium supports VAAPI, this uses libva. sigh Why does this Linux hardware decoding story always repeat itself. :-(
Still, raw CPU may let it manage at least 1080p at 30 fps but I can't say for sure for anything more.
https://github.com/popcornmix/omxplayer and Kodi are the only ones I've found that handle it correctly (and those are related/share code) - that means Kodi is the only place to play 1080p or larger youtube video (omxplayer can stream video from youtube, but doesn't by itself handle the separate audio and video streams).
Looks like there is a way to enable hardware decoding in Chromium, at least on Raspberry Pi OS:
https://lemariva.com/blog/rss/raspberry-pi-4-video-accelerat...
https://lemariva.com/blog/rss/raspberry-pi-4-video-accelerat...
These days the browser is by far the biggest RAM and CPU hog that runs on my system. All the other native stuff is an order of magnitude faster. It's the main reason I'll be replacing my laptop with a Zen2 or ideally Zen3 one as soon as I can find an adequate model. For everything else the Pi would be ideal but the modern web is incredibly inefficient and browser video very poorly optimized.
I'm hoping for a Pi 400 with a full-size HDMI port, an integrated track pad, an M.2 slot, and at least the option of more RAM.
Adding slots would definitely increase the cost, which makes it slightly less accessible. At the end of the day, this computer is a toy, it has limitations and that's OK.
However, I'm with you on the full-sized HDMI ports. I don't know why they went with dual mini ports instead of one full-sized port? I think that people wanting to run this with dual monitors will be the clear minority. They could have actually reduced cost with one full-size HDMI port, because the HDMI adapter cable would no longer be needed.
However, I'm with you on the full-sized HDMI ports. I don't know why they went with dual mini ports instead of one full-sized port? I think that people wanting to run this with dual monitors will be the clear minority. They could have actually reduced cost with one full-size HDMI port, because the HDMI adapter cable would no longer be needed.
"a blog from someone who had milled out the keyboard and integrated a Raspberry Pi 3 Model A+ into it"
Us, then? Haha! The dates check out:
https://blog.pimoroni.com/putting-a-raspberry-pi-3-a-in-the-...
Us, then? Haha! The dates check out:
https://blog.pimoroni.com/putting-a-raspberry-pi-3-a-in-the-...
i'm suprised they didn't add a link!
Why keyboard manufacturers remove Page Up, Page Down? They sit near cursor and works nicely with browsing.
Would you have made the keyboard one column wider or weirdly jam them around the arrow keys and then incur the wrath of the Home/End key fans? Personally I think I prefer what they did to minimise the width and provide them all as alternate functions of the arrow keys. I think this is always going to personal preference though.
I am glad at least Fn is not swapped with Ctrl. I would prefer to jam them around the arrow keys, alternate Home/End with Fn.
100% with you there. Swapping Fn with Ctrl is a serious keyboard crime. Thankfully I've not had to deal with that since my old, old, old laptop That was ~15 years ago and it still annoys me just thinking about it.
By remapping caps lock to control, one doesn't have to worry about it - all the control key available that one could need :)
This drives me nuts too. Many laptops have the same problem, fortunately Dell Latitude and Lenovo Thinkpad have the dedicated PgUp and PgDn and these are good laptops. Screen-wise it's the same battle for matte displays (nearly everything seems to be glossy nowadays).
One thing that excites me the most is the hackability of the "included" case. Enough room for a battery, supercap, switches, normal HDMI ports, and still having free of clutter the GPIO pin rows.
I could also expect a 3D printed detachable LCD bezel/case connected directly to the microHDMI port and GPIO power rails. But well there are already some raspi based laptops for that matter.
I still like the R400 as a "presentation keyboard". Battery pack and HDMI adaptor and it's connected to the classroom projector.
I could also expect a 3D printed detachable LCD bezel/case connected directly to the microHDMI port and GPIO power rails. But well there are already some raspi based laptops for that matter.
I still like the R400 as a "presentation keyboard". Battery pack and HDMI adaptor and it's connected to the classroom projector.
There's surprisingly little room inside- I've been trying to find somewhere to fit a tiny SSD, but without tossing out the heat sink (arguably one of its strengths since it keeps the temperature in check) it's a really tight squeeze.
It's also an absolute horror to get open- no screws, just plastic clips all around the outside edge. First try took a good 10 minutes of prying.
It's also an absolute horror to get open- no screws, just plastic clips all around the outside edge. First try took a good 10 minutes of prying.
What kind of SSD would be small? Those with a M.2 slot? Or there are actually small form factor SATA cable SSD's?
Either way, you would need an extra USB adapter I guess.
EDIT: Regarding the heat sink, with the numbers some reviewers have shown shouldn't there be enough material to shed and still having it working fine overclocked? Granted, you lose the very well designed heat sink, but that's part of the hacking. It was not meant to work that way.
EDIT: Regarding the heat sink, with the numbers some reviewers have shown shouldn't there be enough material to shed and still having it working fine overclocked? Granted, you lose the very well designed heat sink, but that's part of the hacking. It was not meant to work that way.
I was happy to see the C64 called out near the end of this. I love that machine, and the Amiga so much. And reading about this Pi 400 the other day truly struck me in the same vein. I honestly don't care much about the couple obvious shortcomings, for $100, this is a purely nostalgia purchase for me.
I could do with some case color options, but that's a small niggle given what this thing can do. And I appreciate the focus on price point. Old school design constraints.
I could do with some case color options, but that's a small niggle given what this thing can do. And I appreciate the focus on price point. Old school design constraints.
Have you looked into the Atari 8-bit home computers (800, 800XL, 130XE)? They were designed by the same people who designed the Amiga (eg. Jay Miner) and are basically 8-bit Amigas.
Yep. I had a C64 and my step-brother had an Atari 800. It was a cool machine as well. Same processor, but radically different graphics and sound chip, if I remember correctly.
I got my Pi 400 today. Unfortunately the USB-C port does not work with external monitor, it's only for charging.
I was hoping I would have just one cable going from the Pi to my monitor. Maybe it will be possible in the future via a software update?
I was hoping I would have just one cable going from the Pi to my monitor. Maybe it will be possible in the future via a software update?
No, the USB-C connector is only used for power, and USB 2.0-speed OTG 'gadget' functionality.
In the current incarnation of the Pi 4/400/CM4, there is no way to have a USB 3.1 type-C connector that passes through data, video, etc.
In the current incarnation of the Pi 4/400/CM4, there is no way to have a USB 3.1 type-C connector that passes through data, video, etc.
The one thing that makes me happy about Raspberry Pi (and its Raspbian OS) vs other Linux build is that it really reminds me of the early days of Personal Computer revolution.
Raspberry Pi, similar to early Personal Computers, is so hackable and approachable. It's a great platform for teaching how computer works to people who are interested.
Raspberry Pi, similar to early Personal Computers, is so hackable and approachable. It's a great platform for teaching how computer works to people who are interested.
> "The PCB shape had to be defined early on so that the industrial designers could get on with the housing design, and I then stared endlessly at the PCB layout, trying to get one of the USB ports to route to the right side without wrecking the signal integrity of the memory or the HDMI; I could not find a way to do this. "
I'm not an electronics designer, but why would some kind of a symmetry of the PCB not work?
I'm not an electronics designer, but why would some kind of a symmetry of the PCB not work?
See this image from my tear down [1]: https://www.jeffgeerling.com/sites/default/files/images/4-pi...
You can see it's hard to find a good path from one side of the board (where the usb controller is located) to the other (where the HDMI ports are located) without using some vias or some crazy routing. The HDMI ports could be relocated probably but at the expense of more layers on the PCB (higher cost) or rotating the SoC, which would then necessitate even more of a redesign.
[1] https://www.jeffgeerling.com/blog/2020/raspberry-pi-400-tear...
You can see it's hard to find a good path from one side of the board (where the usb controller is located) to the other (where the HDMI ports are located) without using some vias or some crazy routing. The HDMI ports could be relocated probably but at the expense of more layers on the PCB (higher cost) or rotating the SoC, which would then necessitate even more of a redesign.
[1] https://www.jeffgeerling.com/blog/2020/raspberry-pi-400-tear...
If you look closely at that image, and at the image of the other side of the board (https://www.jeffgeerling.com/sites/default/files/images/3-pi...), it's fascinating. The keyboard is USB 2 (as mentioned in the article, "one of the USB2.0 ports is dedicated to the keyboard") with its connector is on the right side, and the designer did find a good path from one side of the board to the other, using some crazy routing. It goes between the two USB 3 ports, and then below all the other ports until it reaches the right side, where it passes right next to the antenna and below the wireless chip to reach the keyboard connector. It's a tight fit, and there's no space for another pair.
This seems to be an interesting and common problem (is there is a name for that?). If ribbons or additional pcbs are out of question, maybe a specialized / dedicated IC (I would describe its function as topological-only / electrically null) would work, I wonder if such ICs exist.
The two-pin version certainly exists and is sold as "zero ohm resistors" in surface mount packages. The multi-pin version probably exists but I can't find it with 30 seconds of searching.
But then there are two problems: controlled impedance and buried layers. Both the signals in question, HDMI and USB, are high-speed, and design recommendation will be that they cross as few vias as possible. They will be on "microstrip" paired line arrangements carried inside the board on one of the inner layers, while the top and bottom layers are ground planes. This won't be visible from a simple photograph of the board, you need an xray or the original Gerber files.
So while it's possible if you have enough space to punch a signal up to the surface of the board, through a package, and back down again in a different place, that will usually have an effect on signal integrity.
The normal solution is more layers. I don't know how many are there at the moment but I suspect it's 4. Increasing that to 6 costs more - not quite 50% more, but heading that way.
But then there are two problems: controlled impedance and buried layers. Both the signals in question, HDMI and USB, are high-speed, and design recommendation will be that they cross as few vias as possible. They will be on "microstrip" paired line arrangements carried inside the board on one of the inner layers, while the top and bottom layers are ground planes. This won't be visible from a simple photograph of the board, you need an xray or the original Gerber files.
So while it's possible if you have enough space to punch a signal up to the surface of the board, through a package, and back down again in a different place, that will usually have an effect on signal integrity.
The normal solution is more layers. I don't know how many are there at the moment but I suspect it's 4. Increasing that to 6 costs more - not quite 50% more, but heading that way.
Perhaps they could have added some grooves or small plastic hooks outside to route USB cables.
pjc50(2)
things i'd like to see in future iterations - hopefully ordered by BOM cost (have zero experience with hardware design):
- RTC (for the battery replacement argument - I'd be fine using an AA/AAA battery if that's a thing - it is a thing for a couple of my kitchen clocks, though)
- female GPIO
- headphone/mic jacks or combo jack
- full-size HDMI port
- 8 GB RAM
- NVME storage option
- battery
- display
- RTC (for the battery replacement argument - I'd be fine using an AA/AAA battery if that's a thing - it is a thing for a couple of my kitchen clocks, though)
- female GPIO
- headphone/mic jacks or combo jack
- full-size HDMI port
- 8 GB RAM
- NVME storage option
- battery
- display
A slightly Bigger case (the Pi 800) could take some of those internally if you are going to add jacks please make it separate ones) or have space for a proper audio hat
For anyone who missed it, there has been a massive discussion about the device over the past couple of days.
https://news.ycombinator.com/item?id=24965614
https://news.ycombinator.com/item?id=24965614
Just realised there's a cheaper "RPi 400" - if you search for "computer" instead of "kit" you should find it. Save 20-30 GBP.
Important to note: the option on their site labeled "computer" rather than "kit" has (AFAIK): no power adapter, no mouse, and no micro-to-regular HDMI cable. Also no included book.
Plenty of HN users probably have some or all of these things lying around, but it's important for people to know what they are (or aren't, in this case) buying.
Plenty of HN users probably have some or all of these things lying around, but it's important for people to know what they are (or aren't, in this case) buying.
Will this keyboard be available in layouts other than UK/European?
I ran into some nationalistic issues (“this is a UK product”) with the RPi people when trying to get them to stop explicitly setting a uk locale on their default images.
I ask because I run into issues using a keyboard that has enter where I am used to backslash being.
I ran into some nationalistic issues (“this is a UK product”) with the RPi people when trying to get them to stop explicitly setting a uk locale on their default images.
I ask because I run into issues using a keyboard that has enter where I am used to backslash being.
The article states (near the bottom):
> Raspberry Pi 400 computer with choice of six keyboard countries (more to follow)
You could probably expect the same layouts that they already do for their normal keyboard. They do Japanese but that appears to be about it outside of Europe and North America.
However, from https://www.msn.com/en-in/money/technology/raspberry-pi-400-...
> At launch, there are six different region-based keyboard layouts - UK, US, German, French, Italian, and Spanish. The company told The Verge that there are additional variants for the Norwegian, Swedish, Danish, Portuguese, and Japanese markets on the way. The Raspberry Pi is available in the US, UK, and France initially, with availability in Italy, Germany, and Spain starting next week. The company also plans to bring the Raspberry Pi in markets like India, Australia, and New Zealand by the end of this year.
So maybe there will be some Indian layouts? Note: I have no idea if that is a thing.
> Raspberry Pi 400 computer with choice of six keyboard countries (more to follow)
You could probably expect the same layouts that they already do for their normal keyboard. They do Japanese but that appears to be about it outside of Europe and North America.
However, from https://www.msn.com/en-in/money/technology/raspberry-pi-400-...
> At launch, there are six different region-based keyboard layouts - UK, US, German, French, Italian, and Spanish. The company told The Verge that there are additional variants for the Norwegian, Swedish, Danish, Portuguese, and Japanese markets on the way. The Raspberry Pi is available in the US, UK, and France initially, with availability in Italy, Germany, and Spain starting next week. The company also plans to bring the Raspberry Pi in markets like India, Australia, and New Zealand by the end of this year.
So maybe there will be some Indian layouts? Note: I have no idea if that is a thing.
I'm very curious to know if the US layout avoids the problem with squished keys around the return key on the UK layout...
The US layout is not squished - you can see it in the product brief https://datasheets.raspberrypi.org/pi400/pi400-product-brief...
Wow, the US layout is the only "sane" one; all 5 others have a 2-row return key and squished keys surrounding it.
Totally loving this project now:-)
Totally loving this project now:-)
> I ran into some nationalistic issues (“this is a UK product”)
With the rest of the world defaulting to US-english locale in all kinds of settings, one might forgive the exception
With the rest of the world defaulting to US-english locale in all kinds of settings, one might forgive the exception
I bought it with a US ANSI layout in the UK - no problems, in stock, same price, delivered next day
In the difference between the US and UK keyboard layout just the currency symbols?
It's slightly more than that. For example the return key is much bigger in the UK and some of the shift+number keys are different (eg # is moved).
The UK layout has an extra key (allowing for £ and ¬) and the European "tall" shape Enter key.
These symbols are in a different place: @ " # ~ \ |
These symbols are in a different place: @ " # ~ \ |
> stop explicitly setting a uk locale on their default images
What locale would you prefer they set? C?
What locale would you prefer they set? C?
I ordered the Pi 400 for my son along with a cheap 2-port HDMI switch. He has a remote desktop setup with a Chromebook from school. I'm hoping this makes it easy and convenient to use for tinkering.
Something I'm wondering is if they will sell the 400 PCB without the rest of the keyboard attached to it.
It's an interesting form factor and could easily be integrated with other keyboards out there.
It's an interesting form factor and could easily be integrated with other keyboards out there.
MM I wonder if I could fit one into my IBM Type M
I believe there should be enough space for that.
Might need custom code to support PS2 that the Model M outputs.
Might need custom code to support PS2 that the Model M outputs.
XT connector for the M you thinking of the F on the AT
I really like this design. Just in time for Christmas gifts...
Where are these manufactured?
edit: especially curious about the keyboard
edit: especially curious about the keyboard
The article mentions "Sony’s manufacturing facility in Wales".
Yeah - I should have been more specific. They make PCBs in the UK and the article mentions final assembly in Wales, but I'm wondering where the keyboards are made. (it would be quite interesting if they have that capability in the UK)
Am I the only one disappointed to discover that it has a custom all in one PCB instead of being based on the compute module interfaces?
This was addressed in the post:
"Some folks have asked us why we did not fit the Raspberry Pi Compute Module inside. The reason is that above a certain scale, it generally makes more sense to go with a custom PCB rather than a module with a carrier board. With hundreds of thousands of Raspberry Pi 400 units in the first instance, we are above that scale."
"Some folks have asked us why we did not fit the Raspberry Pi Compute Module inside. The reason is that above a certain scale, it generally makes more sense to go with a custom PCB rather than a module with a carrier board. With hundreds of thousands of Raspberry Pi 400 units in the first instance, we are above that scale."
What is the benefit of a compute module interface for this product? You will need a second PCB and additional connector which adds cost.
The keyboard (and ports) will probably hold up a lot longer than the compute power of the Pi 4, so being able to swap out the internals without throwing away the perfectly good chassis would be a nice win for e-waste.
Now I'm looking forward to see people making custom mechanical keyboard projects with the RPi unit from this kit.
Does anyone have a definitive answer how many Hz the Pi runs on a single 4k monitor?
Single 4k display can be driven with 60Hz, both outputs with 4k can only output 30Hz.
[0] https://www.raspberrypi.org/documentation/configuration/hdmi...
[0] https://www.raspberrypi.org/documentation/configuration/hdmi...
Wait, what? They used the terrible mini HDMI to cram 2 ports onto the Pi 4 just so that it can claim dual 4k at 30hz? Ugh that's a terrible compromise, hopefully the Pi 5 corrects back to just a single full-size HDMI port...
Not everybody needs 4k, so perhaps a lot of people are happy they can have a dual screen setup in FullHD with the Pi4 now.
60 Hz if you enable it in the settings, and if your cable and monitor both support it (my monitor doesn't—though it supports 60 Hz through DisplayPort). 30 Hz otherwise.
They say 60hz pretty consistently
I'm pretty excited about this. Awesome they fixed the cooling issues.
Does this work as a regular keyboard for other systems too?
That would be kinda cool, not sure if it could be hacked to do that as I know it has USB host ports and if you could present them to another device as a client port - I just don't know.
If you could - be the ultimate keylogging keyboard.
Me - I'm still trying to find out if the power button is a hard power cut-off or a soft one which will allow a graceful shutdown.
If you could - be the ultimate keylogging keyboard.
Me - I'm still trying to find out if the power button is a hard power cut-off or a soft one which will allow a graceful shutdown.
"Power off is achieved by holding down Fn+F10 for two seconds. This is a soft control that negotiates with Linux to shut down, so you don’t corrupt your memory card or your USB drive. Power can be restored by pressing F10 (or Fn+F10)."
Thank you thank you thank you. That is good to hear, making the Pi 400 a way better option for so many for just that feature alone as standard.
The keyboard matrix driver is on the main board, and there’s no access to the USB2 bus that connects the matrix driver to the USB controller. So you would have to run the whole Raspberry Pi in USB “gadget mode”, so it pretends to be a device rather than a host. The USB-C power port can also support USB-2 OTG in gadget mode (but it has no high bandwidth features).
The concept is super cool (although hardly original) but I have an Idea of what to add: make a dockable display with built-id battery (to power itself and the Pi) so people would be able to carry it around and use their PIs anywhere like laptops.
And, by the way, I can see no reason to use micro HDMI in this version - there's a lot of spare space, why not put full-size HDMI ports? Given so much unused space I personally would even add a USB hub.
And, by the way, I can see no reason to use micro HDMI in this version - there's a lot of spare space, why not put full-size HDMI ports? Given so much unused space I personally would even add a USB hub.
> I can see no reason to use micro HDMI in this version - there's a lot of spare space, why not put full-size HDMI ports?
So to be clear: you are rejecting the board designer's assessment that this was not possible without sacrificing something else?
So to be clear: you are rejecting the board designer's assessment that this was not possible without sacrificing something else?
Yes.
From the article: "It would have been lovely to have had full-size HDMI connectors, but in order to achieve this we would have to remove other functions, or make a bulkier unit."
That explanation sounds like BS. Full size HDMI is still shorter than the ethernet jack, so vertical space is there. Width would be the only restriction, but there's plenty of that, too.
As an aside to this- they'd already built an ecosystem around micro HDMI with the Pi 4 so changing it to full-sized HDMI would probably have irritated just as many people as not. They're also more economical to run through a pick-and-place machine, I believe.
Additionally, a little tidbit not included in this article:
"Also, full-sized HDMI connectors have no lead-in (to funnel the connector in). Whereas the micro-HDMI ones do, this makes auto-insertion of the connectors possible when testing which means we can do testing through the connector. This makes it cheaper and more reliable..."
Source: https://twitter.com/gsholling/status/1323322997315411971?s=2...
Additionally, a little tidbit not included in this article:
"Also, full-sized HDMI connectors have no lead-in (to funnel the connector in). Whereas the micro-HDMI ones do, this makes auto-insertion of the connectors possible when testing which means we can do testing through the connector. This makes it cheaper and more reliable..."
Source: https://twitter.com/gsholling/status/1323322997315411971?s=2...
> Also, full-sized HDMI connectors have no lead-in (to funnel the connector in). Whereas the micro-HDMI ones do,
That's an interesting point I didn't know. Thanks.
That's an interesting point I didn't know. Thanks.
Every penny of cost had to be an issue. The RJ-45 jack doesn't have link/activity LEDs.
Ok. Make a bulkier unit.
It's fairly likely that third parties will make some kind of somewhat-dockable display+battery. The choice of micro HDMI likely will help with some designs of that kind of accessory, given how large the strain reliefs of full-size HDMI cables tend to be. Although I agree with you that for most uses providing at least one full-size HDMI port would have been ideal.