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Comment by geerlingguy | Hacker News Reader

I was lucky to get a pre-release version to test, and I decided to tear it down before I started trying it out. I posted this blog post with detailed pictures of the insides, and some more details and performance benchmarks: https://www.jeffgeerling.com/blog/2020/raspberry-pi-400-tear...

There are also a couple videos linked in the post, if you're more visually-inclined.

Fun fact: the Pi 400 (and Compute Module 4) both have newer revisions of the BCM2711 SoC (C0 instead of B0), and that's part of the reason the clock speed is higher on the Pi 400 (1.8 GHz) than on the regular Pi 4 model B (1.5 GHz)—the newer revision apparently handles faster clocks and scaling with less heat than the older revision.

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Just watched a few videos on your channel and love it. Really great stuff.

I love this Pi 400 and think in the new year I will pick one up for my son. We have a Pi 4 that we use a lot and he loves but like you say in your video it is a bit annoying with this little box off the side with a bunch of cables coming out of it.

Not terrible by any means just annoying so I really love the form factor of it all being in the keyboard.

I have thought for a while now they should do this kind of form factor or sell a simple RPi branded monitor with a Pi built in so I am happy to see they thought about it too. A keyboard is much more practical than a monitor of course so it is a far more sensible choice!

Really hope this sells well and they continue with this kind of form factor in the future. Even a slightly bigger keyboard with a "forehead" (C64 vibes) would be excellent.

>simple RPi branded monitor with a Pi built in

Oh, I'd definitely be up for that!!

And make it easy to upgrade or replace later on!

You could probably DIY that with an RPi case pretty easy, using the VESA mount holes on the back of the monitor. Most of my monitors have two different size VESA mounts, and my monitor mounts use the smaller size, meaning I have 4 extra screw holes on the back of all my monitors, and conveniently nearly all the VESA mounts take standard M4 bolts.

If your VESA mounts are close enough together, you can just drill holes directly in the RPi case and mount it to the back of the monitor. If they're too far apart, use the mounts to put in a plastic or wood bar, then drill holes through the RPi case and the bar (while not attached to the monitor), then mount the case to the bar and the bar to the monitor.

I've looked at doing similar in the past, but I wanted to make the mounting block along the bottom of the monitor with the SD card exposed. That way I can set up a series of SD cards to test with. Want to test something on Ubuntu 18.04? Cool, switch monitor 2 to input 2 (the RPi) and then swap the SD card out to the Ubuntu 18.04 one and you're ready to rock. It's not as easy as a Docker container, but I'm often using the GPIO pins and I don't have the desire to try to make GPIO pins work in Docker. It might not even be that hard, I just don't feel like adding another step to my troubleshooting.

I feel like this is the opposite direction of the 400 ...

Of course, that requires that your monitor have VESA mounts. It seems the big brands have segmented the market by making VESA mounts a “premium” feature. Which is ridiculous if I can get a TV with a bigger screen for the same price that comes with VESA built in to any of them.[a]

[a]: Ignoring the obvious differences between a TV-as-a-monitor and an actual monitor

I’d rather have a miniPC-sized Raspberry Pi computer like an Intel NUC or Mac Mini* mounted on the back of a monitor instead of an all-in-one. Monitors have a much longer useful life so all-in-ones (e.g. iMac) eventually become paperweights or e-waste.

If they go the all-in-one route they should include an external HDMI port and a switch to choose between it and the internal Raspberry Pi.

*: But upgradeable and repairable.

Exactly, this is what the VESA mount on the back of your monitor is for. For an almost no effort solution, you can zip tie a pi to the mount bracket and screw it in (some monitors may even be able to power it via usb). Integrating into the monitor's electronics makes no sense.

> Integrating into the monitor's electronics makes no sense.

Them's fighting words to a NEC C651Q owner.

You can also get pre-built mounts and cases to attach a pi to the VESA mounts, e.g. https://shop.pimoroni.com/products/omnivesa

I have a NUC but I could never mount it to the back of the monitor because the monitor stand/arm itself uses the VESA mount location.

If the stand/arm is using the actual VESA mounting holes, there are brackets that can hold a NUC either to the side or sandwiched between the stand/arm and the monitor.

This is pretty much how I had things setup but it isn't ideal as getting to the Pi is a pain and it doesn't work well with any hats so it didn't last long.

My thinking for a Raspberry Pi monitor would be to have the ports in an easier to access location on the rear of the monitor so hats, etc. can be made to a standard design.

Of course the monitor will likely out last the Pi inside it but there is nothing to stop it being used as just a monitor one the Pi instead is no longer useful.

agree the keyboard-in-one is great -

also fyi the pi-top project has a DIY 'all in one' for the PI:

https://www.pi-top.com/products/pi-top-ceed

and a DIY laptop:

https://www.pi-top.com/products/pi-top-3

only claim pi-3 compatibility at the moment, not sure if it would still work with 4, probably need some adapters or so

(maybe other projects like this, not sure)

> Fun fact: the Pi 400 (and Compute Module 4) both have newer revisions of the BCM2711 SoC (C0 instead of B0), and that's part of the reason the clock speed is higher on the Pi 400 (1.8 GHz) than on the regular Pi 4 model B (1.5 GHz)—the newer revision apparently handles faster clocks and scaling with less heat than the older revision.

Reading your article

> the Pi 400 didn't overheat even when I was running it with an overclock to 2.147 GHz, the maximum it allows currently

This only makes me wish they sold an 800 version with 8 GB of RAM, just like the Pi 4.

... and a mechanical keyboard, to complete the possibly unintentional Atari reference.

(Folklore says the original product plan had the Atari 400 come with 4K of RAM, and the 800 8K... and then memory got cheaper by release.)

Just wanted to say that I've been watching your Pi videos on YouTube over the last few months and I really enjoy them. Your video about trying to get a GPU working with a Raspberry Pi was particularly fascinating. Keep up the great work.

This is slightly disappointing, I was expecting it to be some kind of case for the the Compute Module (or at least for the RPi4. I don't know if it's unrealistic, but it would be nice to have some sort of upgrade or repair possibilities.

That seems to more or less already exist: https://shop.pimoroni.com/products/raspberry-pi-keyboard

Sorry, that's just a keyboard with a USB hub.

I agree, I wish this was the case but it's still a compelling gift for my nieces and nephews and tickles my nostalgia for the era of computing that it mimics.

How is the keyboard? It looks, uh, cheap, so I'm curious if typing on it is an ok experience.

At least superficially it looks like it might be the same basic keyboard as the official Raspberry Pi keyboard that they already had. If so the experience is... not great but not horrible. It's not the worst chiclet keyboard I've used, I'd rate it as adequate. You would not want to use it as your primary keyboard all day, but that's also not what it's intended for.

(This is assuming the existing keyboards are the same) Pretty decent scissor-switch, but one of mine squeaks when typing some.

The Pi Keyboard was decent. I would expect this to be the same just with the Pi integrated.

This is literally the exact same keyboard surface and mechanism as the Pi Keyboard, so it's good, not amazing.

I can type fine on it, though I still prefer an Apple Magic Keyboard (latest version) for daily typing since the body of it is slightly more solid.

I'm not a mechanical keyboard fan, though I know many would like that kind of keyboard here, and it would be more fitting for the nostalgia!

Some of the '80s home micros like the Sinclair ZX81 and ZX Spectrum and the Atari 400 had keyboards which were dire by modern standards, or in fact by contemporary standards. Even the "mechanical" keyboards with full travel tended to be disappointing https://www.youtube.com/watch?v=KNa2UdagTGU https://www.youtube.com/watch?v=sN8WHp_QmoE . In comparison the RPi 400's keyboard is probably well above the mean. Still we might see some third-party replacement cases with mechanical keyboards, like the ones which came out for the ZX81: https://k1.spdns.de/Vintage/Sinclair/80/Peripherals/Keyboard... https://k1.spdns.de/Vintage/Sinclair/80/Peripherals/Keyboard... .

Apple made the chiclet keyboard cool again. It might be OK.

Gen-x who remember the TRS80 MC10 and its keyboard remember chiclet keyboards as not much better than membrane keyboards (Consider the ZX81 Spectrum)

But decades later Apple started shipping chiclet-appearing keyboards that actually worked, so the style has been somewhat revitalized.

That said, yeah they could be shipping a 1980s quality chiclet keyboard or a 2020s quality chiclet keyboard, so that's worrisome.

I have a hard time believing there is a chiclet keyboard worse than the Atari 400 membrane.

"Gen-x first computers" sounds like an interesting site

> Atari 400 membrane

But at least it was waterproof! Thank goodness they saw the light and used a proper keyboard on the 800.

Actually there were differing qualities of these manufactured. I had one of the early ones and it was fantastic, I could run my fingers touching over the surface and lightly depress while dragging and the audible feedback had such low latency: joy. Sort-of regretted replacing it with mechanical keys. Later Atari 400s had barely registering keypresses that was a workout for your fingers.

I must have had a later one then.

Where did you find a replacement mechanical keyboard for the 400? I never found one. I was so envious of the Sinclair owners because they had tons of options.

I think it might have been a local creation. It was ugly as hell, half of it rose above/outside the case showing the switch bodies and entire keycaps. It did have a good feel though. I wasn't much of a touch/speed typist so didn't gain so much. I got it because my father was a bit of a typewriter geek and didn't like me using the membrane keys. Ended up getting an 800 with expansion memory but the keys weren't as good--too springy/spongey no clickiness in it's motion.

The modern Apple "chiclets" seem to be really just low-travel scissor keys. "Real" chiclet keys as seen on the ZX Spectrum or the original PCjr keyboard https://www.youtube.com/watch?v=l5yIg5wmf6I were something else again. (The ZX81 was a separate, earlier computer, with a very different and even worse keyboard.)

When I was around 7 years old, our family was manufacturing ZX81, ZX Spectrum and Enterprise foil-keyboards, because the factory ones were just shit and died within a year or two.

they were all the same design. 3 layers of plastic foil. 1 for horizontal wires, 1 for vertical wires to create a matrix and a 3rd sheet of foil between them with holes, so the horizontal and vertical wires can contact when pressed.

before that, when I was around 6 years old, I remember my father was sticking round aluminum foil stickers on his finger and type directly on a keyboard made out of a PCB with a key matrix.

The keys were the shape of 2 combs facing each other and you had to short them by touching them with the alu stickers on his finger.

It was an AirComp II computer, iirc. I can't find any references to it online now...

> Apple started shipping chiclet-appearing keyboards that actually worked

Sony was already using that style of keyboard at the time, so although Apple contributed to the momentum, they didn't start the trend.

Or alternatively, how hard is it to plug in and use another keyboard instead?

You'd just connect a USB keyboard and I'm about 99% sure it would work perfectly.

It feels plasticky, but not flimsy. I think it uses scissor switches, so it feels better than a standard rubberdome, but it's obviously not going to replace your Model M or Cherry-switch keyboard.

Sauce: I have the keyboard without the computer in it, from when I bought a Pi 4 "starter kit" a year ago.

Excellent, I was looking for this sort of info.

(side note, I love the ansible roles you've made, especially AWX, saved me a bunch of time back in 2018)

Hey Jeff, I recently bought the RPi Keyboard Hub (Pictured in OP and In parent blog) for its soft keys (Got bone issues), I was pleasantly surprised with the quality. I use Wacom Touch Tablet for trackpad along with a Steel series mouse in its Hub; But I'm worried about saturating the bandwidth as it's just USB 2.0 although I haven't found any conclusive issues.

Have you tested the Keyboard hub's limits? Controller seems to be QinHeng Electronics USB-Serial.

Edit: It looks like they're affiliate links for monetization, so what I said doesn't apply in this case as they're not the usual tracking crap Amazon et al commonly add to their sharing links.

---

You might want to replace the link to the plexiglass cutter to remove the tracking info (linking everyone who clicks it back to you); here's the smallest you can get it:

https://www.amazon.com/dp/B000BZZ1D0

The same goes for your SD card links.

Can you use the keyboard.... as a keyboard for other computers?

With a little bit of code, you should be able to pipe keyboard input to one of the USB ports.

There's a project that did that but for a different purpose - a network KVM using a Pi4 - https://mtlynch.io/tinypilot/

It had to use the one USB-C connector that's used for power for emulating the keyboard and mouse since that's the only one that supported USB-OTG. So you kind of either need PoE or another adapter to both power the device and be able to hae the Pi act as an input device.

One of my main uses for random keyboards is hooking them onto a raspberry pi that needs some local debugging...

Yes, I think Gordon Hollingsworth from Raspberry Pi has posted somewhere specifically how to do it (maybe in the comments on the post on the Pi website?).

Found it! Merci :)

>It would be possible to do this, but you’d have to run a simple buildroot SD card which runs a suitable dwc2 OTG HID driver to pretend it is a keyboard…

Otherwise, you can use the Pi 400 as a Barrier server to the other computer… See my other blog post for details!

Gordon

Nice, it's probably using the USB gadget functionality. That probably means you could modify the image to access a bunch of the ports. Having the ability to turn my Pi Debugging Keyboard into a USB Ethernet adapter would have some advantages.

Yeah lots of interesting possibilities to think about!

Here's an interesting idea:

A build of KeePass that uses the OTG mode for autotype. You plug the Pi 400 into a USB port on your device (whether computer, console, or whatever) and the password file is never on the computer in the first place.

Edit to add:

Might work better with a tablet build of the Pi, though, and you'd probably still want it to sync the file to Dropbox or some other storage place for safety.

Hold on, so you could plug it in to autotype a password?

That's precisely the idea, yeah. It's entirely possible with the hardware, the software (e.g. KeePass) would need to be modified to send through the gadget mode USB device.

You should probably be able to use Synergy (https://symless.com/synergy)

Have you tried the coffee spilling test on it yet?

On the subject of heat, how is it on this thing? I've heard stories about the Pi 4 B.

There's an aluminium plate that serves as a heat sink and appears to work quite well, apparently.

According to the article, it isn't a problem; the heat sink is big enough to not need a fan. Nice bonus that it's a slightly faster SoC.

I have a Pi 4B with a heat sink and fan that's running BOINC 24x7 (yielding a RAC of about 750-775 on World Community Grid), and with the fan connected to 3.3V it runs at a comfortable 52-54°C with absolutely no throttling. I think I'm going to try overclocking it a bit and see how it handles it.

They pushed out a firmware update last year that apparently solves some of the heat issues.

https://www.raspberrypi.org/blog/thermal-testing-raspberry-p...

It runs cooler than the Pi 4 model B, at a higher clock speed. The newer chip helps with that, in addition to the massive heat sink on top of it!

One comment regarding your "performance comparison" graph. Is the "dd" result read or write? I wondered the same thing with your Compute Module 4 post.

It's write speed; sorry about that, I should probably be more specific! All the benchmarks I'm using are from this Wiki page (http://www.pidramble.com/wiki/benchmarks/microsd-cards) — though I need to update that page to include some more USB/SATA/NVMe performance benchmarks since I'm now using a lot more drives with the Pi 4 and CM4 (and skipping microSD entirely for most builds).

Curious if you have any specs on the ribbon cable that connects the keyboard. It looks like it must carry more than USB?

Thank you geerlingguy for your ansible repositories!!

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