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A new Raspberry Pi takes a bow with all of the speed but less of the RAM

Suricou Raven

This is good.

The hub-and-ethernet chip is a real power-sucker. Getting rid of it should substantially reduce power demands. Looks like it sits somewhere between the 3B and the Zero.

technoise

Re: This is good.

Agreed. Anyone can make an SBC with any number of cores and loads of RAM. It takes a special kind of designer to come up with something economical of power, making an SBC suitable for an IOT type use case, filling the gap between embedded microcontroller boards and office capable computers.

I'm already somewhat annoyed by the use of 5v on a micro USB port, given the limitations of the port itself for carrying current, which thanks to Ohm's law, has to be greater than if a higher voltage had been used, and makes the system more vulnerable to reduced power thanks to the high resistance leads and connectors that are to be found too often on the typical cheap Chinese power supplies people will be using.

I really wish the designers had gone with a coaxial barrel connector for power all along, which would have allowed the user to specify and solder their own cables.

For this reason, I like the Latte Panda's use of a barrel connector and 12v.

Suricou Raven

Re: This is good.

Us low-power/embedded people are annoyed at the 5V too - but in the other direction. We'd really like to be able to operate a Pi of of 3.3V, which it nearly can already - the processor is a 3.3V component, all the GPIO pins are 3.3V, including the UART. Unfortunately we can't, because the 1.8V for the memory is derived from the 5V rail via a buck converter just like the 3.3V.

If you could power a pi on 3.3V alone it would simplify running it off battery considerably and allow for the use of more efficient power supply circuitry. (li-ion -> 3.3V, rather than li-ion -> 5V -> 3.3V, which adds an extra conversion step where power is unavoidably wasted).

Incidentally, you don't have to power the Pi via micro-USB: The GPIO header includes pins for 5V supply input.

the spectacularly refined chap

Re: This is good.

I'm already somewhat annoyed by the use of 5v on a micro USB port, given the limitations of the port itself for carrying current, which thanks to Ohm's law, has to be greater than if a higher voltage had been used, and makes the system more vulnerable to reduced power thanks to the high resistance leads and connectors that are to be found too often on the typical cheap Chinese power supplies people will be using.

That isn't actually Ohm's law, but simply an inevitable consequence of the way the units are defined, i.e. J/C (volts) times C/s (amps) inevitably cancels to J/s (watts), no scientific law, it's just maths.

I do understand the concern about the power connection but a barrel connector wouldn't be my first choice, I'd prefer the option of something with a positive lock that can't simply be tugged out. Powering using 5V attached to the GPIO port may be an option, how practical that is depends on your application. As for the supply voltage, I suspect that comes down simply to the cost objectives. Dropping the power down from e.g. 12V means either a switching (cost) or a linear (heat!) regulator and either do not allow for the use of a standardised commodity power supply the user may well already have lying around.

the spectacularly refined chap

Re: This is good.

Us low-power/embedded people are annoyed at the 5V too - but in the other direction.

Can't say that I've ever encountered that attitude. Indeed it would make interfacing difficult for the average user case - how can you plug in USB peripherals without a 5V supply for them? I admit havign 5V power but I/Os that are not even 5V tolerant isn't the most comfortable design decision though.

BinkyTheHorse

Re: This is good.

For USB peripherals that may be true, but a significant number of auxillary components, like sensors, run on 3.3V. Having the same voltage requirement everywhere saves cost and complexity, as the other posts outlined.

Suricou Raven

Re: This is good.

The Pi 3 has no less then three switching regulators on board - but they are all operated by a single controller. That's how they got the cost down.

The first pis did use a linear regulator, but recent revisions are all switching.

the spectacularly refined chap

Re: This is good.

The first pis did use a linear regulator, but recent revisions are all switching.

That's a goer for 5V->3.3V since you are scrubbing 1.7V or 1.7W at 1A. Go down from 12V it's then 8.7W disspiated by a linear regulator which is getting into the region where you need to add a reasonable heatsink.

Version 1.0 Silver badge
Happy

Re: This is good.

I expect that it will continue to evolve, I tend to agree with most of the comments here but let's see if it gets updated in a year and the issues addressed.

wobbly1

Re: This is good.

on finished devices i solder the power leads to the +ve and -ve TPs on the underside of the Pi board board below the power USB port. neater safer and more reliable. it reduces the size of the case or housing needed for the board too. I use rock 64s for heavy computing jobs and these have a barrel jack , I still prefer my method on the rock 64s too.

Jason Bloomberg Silver badge
Facepalm

Re: This is good.

If you could power a pi on 3.3V alone it would simplify running it off battery considerably and allow for the use of more efficient power supply circuitry.

Indeed. Saying it's aimed at "space-constrained, battery-powered applications" is rather laughable considering the Pi range is so at odds with being battery powered, requires external hardware, and that loses any space savings the board may offer.

There are probably quite a few people who wanted a 3B+ with reduced size, cost and power consumption, but won't find the reduction in memory size acceptable. I would guess that decision was made so they did not cannibalise their 3B+ sales.

Old Used Programmer

Re: This is good.

From what I've seen, apparently it came down to a decision between a $25 board with 512MB or a $30 board with 1GB.

doublelayer

Re: This is good.

I, to provide the other side, am happy that the power decision was 5V over USB. This allows me to power it from batteries designed for phone use, which you can buy for quite cheaply and which are easy for nontechnical people to use. I can therefore carry all the pieces needed to run the pi in a small container, rather than having to solder a battery power system together. I'll grant that, in a situation where space is very constrained, a smaller 3.3V battery would be preferable, but I don't think that is very frequent. The main reason is that the raspberry pi, as great as it is on most fronts, simply does not run very long on a battery. Even the zero will run for only a day or two on a large battery*. For devices to be placed in a situation without any power, usually much more time will be needed. The small batteries that are easily shoved into a small space will not provide enough lifetime for an independent** system.

*Large in the sense of a USB battery for phone usage. There are some really big ones that will run a pi zero for a week or more.

**There would be advantages for some projects in having a pi run on battery for a period measured in months. Unfortunately, that isn't going to happen.

DropBear Silver badge

Re: This is good.

As widespread (dominant even) as 3.3V is, there's plenty of stuff remaining in a hobbyists toolkit that still needs 5V even without any USB-attached stuff. Completely ignoring that is a no-go even if some people no longer need 5V at all.

technoise

Re: This is good.

Incidentally, you don't have to power the Pi via micro-USB: The GPIO header includes pins for 5V supply input.

Of course, but then you need to take extra care and possibly add your own circuitry because the 5V GPIO pin is unregulated.

bombastic bob Silver badge
Devil

Re: This is good.

well it would depend on your needs, whether it's good or not. in a headless system it might be difficult to configure without mouse+keyboard+monitor. Maybe (temporarily) plugging in a USB ethernet doohickey would help?

bombastic bob Silver badge
Meh

Re: This is good.

"I'm already somewhat annoyed by the use of 5v on a micro USB port"

well the 40-pin connector has power input points on it. But as I recall it uses a linear regulator for the 3.3v (which is simpler overall, and a smaller footprint than a switcher) but NOT ideal for battery operation.

[I guess newer Pi's use switchers and different configs than the earlier ones, though... making this impossible without supplying 5v and not just 3.3v]

Specifically for IOT they may need to re-think the use of the 5V rail and enable you to turn OFF various things (like ethernet) programatically to reduce power. And turn off 'video core' too, when it's not wanted/needed. [boot into a GUI for IoT? no. just no]

Robert Heffernan

Re: This is good.

Here's my $30. An additional $5 for twice the RAM is a no-brainer.

What I really want though is proper Gigabit Ethernet and a SATA port. Given the purchasing power the RPi Foundation would have, Broadcom would easily be able to spin up some Silicon for them that has an integrated GbE, and SATA controllers.

Suricou Raven

Re: This is good.

The original pis, the first generation ones, did use linear regulators. The current revisions uses switching regulators. This was made possible because the production volume grew large enough to have some custom silicon manufactured - a chip which combines all three of the needed regulators into one package, and brings the component count down to an affordable level. It's actually remarkably efficient, but it does make running off of 3.3V rather difficult.

The processor has hardware support for a lot of power management features, including powering down the video - or even powering down entire cores when not in use. Hardware support, but not software support. This capability has been requested many times, but the Pi foundation has concluded they lack the resources to support such advanced and hardware-specific capabilities which would need a lot of kernel modification work.

Wayland Bronze badge

Re: This is good.

Passive Power over Ethernet would make the PI easier to use. You don't need that 48v nightmare. Most home routers run off a 12v PSU and have a little buck circuit to bring it down to 5v. These are very sturdy little circuits allowing 7v to 27v power. The advantage against 5v power is you can run some very long wires such as PoE. Many times I have powered 12v routers over Ethernet with no problems. You simply can't do that with 5v because there is no tolerance for volt drop.

I appreciate why the PI runs off 5v and does not have one of these 12v buck circuits. If there were a way to include a sturdy buck circuit as a hat with options for passive PoE, plug connector and screw terminals then it would mean putting PI in industrial locations much easier. Frankly 5v power is too flaky. With the right capacitors the buck circuit could handle 30v.

teknopaul Bronze badge

Re: This is good.

I thumbs up using standard usb 5v to power a pi. Wish my phones all did that.

defiler Silver badge

I swerved the PoE hat

Got myself a couple of these instead:

https://www.ebay.co.uk/itm/142700706109

They're slung behind tellies so that Kodi works. Plenty of space to hide them there and no moving parts. And plenty cheap too. No more little lightning bolt in the corner from using wall sockets with USB built in.

The A+ might not be a bad idea for my lad. He tools around on RiscOS with the drawing programs and BASIC. Bit more poke, no need for LAN, no need for RAM. It's an original B that's set up there just now.

Charlie Clark Silver badge

Re: I swerved the PoE hat

Last year I got me a set of various extension cables all with USB ports – all with at least 2 with 2 A.

Peter Gathercole Silver badge

Re: I swerved the PoE hat @defiler

I'm pretty certain that RiscOS can only use one of the 4 cores, and certainly won't use the 64bit instruction set, so keeping it on the B is probably a good use of the B.

defiler Silver badge

Re: I swerved the PoE hat @defiler

@Peter

Yeah, you're absolutely right on both counts, but 3x the clock speed! :)

You're also right that I can't think of a better use for the B just now, because Kodi works much better on the B2 and B3s I have.

Charlie Clark Silver badge

New supplier required

Now that Broadcom is an investment company and not a chipmaker then there needs to be a new supplier for the SoC's. Upping the CPU while ignoring the I/O bottleneck will bring very little.

Pascal Monett Silver badge

Funny you should say that. I think that is exactly the argument used back in the day to diss the 486 DX and, if memory serves, it was spectacularly wrong.

Charlie Clark Silver badge

The 486 DX was great, it was the SX that was shit.

I/O is a real problem on any Pi doing real work: eSATA / USB 3 really should be available. Notice I didn't even mention the GPU that hasn't seen a refresh in years: HEVC really ought to be available as well.

WallMeerkat Bronze badge

Day to day the 486 SX was alright as a budget option, certainly seemed a little quicker than a 386.

It was when it came to gaming that it got shown up.

Though it wasn't long before the Pentium-Win95 push and suddenly everyone who had previously had no interest suddenly had a PC.

defiler Silver badge

The 486 DX was great, it was the SX that was shit.

The SX was just the DX without the floating-point unit. Most software didn't use it at the time, so most people would never have noticed the difference.

I'll accept that the initial SXs were just DXs that had failed the FPU tests - that doesn't inspire confidence in their longevity. Then they started disabling the FPU in DXs and selling them cheaper, but finally they had a die with on FPU for the SX chips.

Wasn't an awful idea.

Maybe you're thinking of the 386DX vs 386SX, where the DX had a 32-bit external bus and the SX was only 16-bits so it took two turns to load a word. Again, though, most software was 16-bit DOS at the time. Would that have been a worry? (I honestly don't know if it would have slowed down 16-bit code signiifcantly.) When it came to the Cyrix 486DLC vs SLC, though, there was a noticeable difference.

Suricou Raven

Depends on the work. The Pi has interfaces for I2C and SPI - which may mean nothing to people coming from the PC side, but electronics tinkers recognise those as 'I can plug fifty ADCs, DACs, TFT displays and IO expanders into there' ports. What the Pi lacks is really high-throughput IO, but I don't know if the processor would be up to handling the sheer processing demands of anything faster than USB2 anyway.

SATA would be nice, though. But it'd mean a custom processor. Pricy.

the spectacularly refined chap

When it came to the Cyrix 486DLC vs SLC, though, there was a noticeable difference. Both were essentially 386 chips with the additional 486 instructions bolted on but with no performance enhancements. The SLC was crippled further by using a 16 bit external bus just as the 386SX. People thought they were getting a 486-alike when the reality was was more similar to that 386SX.

phuzz Silver badge

"I/O is a real problem on any Pi doing real work: eSATA / USB 3 really should be available."

Doesn't that come down to philosophy in the end? Is the Pi supposed to be a low cost computer, or just a small one?

After all, if you want Power! then you could pick up (for much more money) an Intel NUC with an i7, SATA3, USB3 and NVME. It's all a matter of cost.

defiler Silver badge

People thought they were getting a 486-alike when the reality was was more similar to that 386SX.

I thought the 486DLC/SLC were significantly faster than the 80386DX/SX - they had a cache that the 386 was missing. But since the 80486SX was about 4x the speed (from memory) of the 80386DX, the DLC/SLC fell way short. Anyway, I think we can agree that the 386 upgrades were a bit pish.

A mate of mine had a 486DLC/25 and it was a bit cack! :)

ThomH Silver badge

Re: New supplier required

Re: switching SoCs, I'm more concerned about the GPU having been essentially in stasis all this time; it still supports only OpenGL ES 2 doesn't it?

I suspect I'm way out on a fringe for caring about the specific version of OpenGL, but it prevents support for the latest WebGL and, well, you know web developers. Something new and shiny through which they can reconstruct less accessible versions of what's already built-in? Yeah, go for it!

bombastic bob Silver badge
Stop

Re: New supplier required

"prevents support for the latest WebGL"

WebGL is overrated, just like 'cloud' and client side scripting, in general. It's like a cancer. Time to re-think it.

So unless movie playback or localized gaming needs "the new, shiny" existing OpenGL should be fine. chasing the bleeding edge isn't something that's part of the design of a device like RPi anyway.

dajames Silver badge

Is the Pi supposed to be a low cost computer, or just a small one?

... or just a computer that doesn't run x86? There are plenty of applications for a Pi for which the alternative would be an Atom or low-end Celeron, or maybe an AMD APU, and I for one am glad to see an ARM-based option too.

Pete 2 Silver badge

the leader becomes the follower

So this looks like it is intended to compete with the Orange Pi Zero+

Originally the FriendlyArm and Orange Pi ranges were brought out as cheap alternatives to the RPi. Often with more features included in the lower price. However the cost saving never really made up for the lack of community support, software or Linux updates. Now we have a "proper" Pi board that will hopefully compete on price (though I have never heard of anyone complaining their computer had too much RAM.

Anonymous Coward
Anonymous Coward

Re: Support.

I got given an OrangePi Android flavour. While nice bit of Hardware, the software never got updated AFAIK, so make it rather moot/useless for my application (Which was to plug it into a TV/speaker as a Google Now assistant... but seeing as it was old Android, I could not get such play apps on it, and 'm no programmer to do my own kernal/os/apps).

James Hughes 1

Re: the leader becomes the follower

Difficult to see how we can be following something that's based on a form factor we originally produced 6 years ago, and uses two thirds of our naming scheme.

TBH, I'd never head of the Orange Pi Zero+

Lee D Silver badge

I'm beginning to like the RPi's again.

I was an early adopter / tester for the original and their hardware was quite bad, and their educational focus was all-front-no-action (still is).

But the RPi is now a cheap, viable, fast, powerful, multicore, PoE-powered, small, ARM Linux machine with Ethernet, Wireless, Bluetooth and HDMI.

I now look at the things my workplace use on the network and the Pi is capable of replacing half of them - PoE powered tannoy, PoE powered phones, PoE powered CCTV, vehicle GPS trackers, hell, you can make a Pi-powered smartphone if you like.

I have one with RetroPie, also running Kodi, using the DVB-T hat (that was just released), plugged into an aerial, connected to a projector, offering TV on-screen and out over my network (using tvHeadend), PVR functionality, and just one button away are all my old games and a ton of open-source ports. It uses an XBox 360 USB dongle to connect a bunch of gaming pads, plus I've wired in a couple of "arcade style" buttons/joysticks, a Logitech G27 wheel-set and a Bluetooth keyboard (because you can't play Speccy games with only a joystick!).

If I ever fulfill my dream of buying an arcade cocktail cabinet, then that machine is more than capable of running it and controlling all those inputs, for all the games I like, and being the "TV" by offering HDMI out.

Anonymous Coward
Anonymous Coward

Another Raspberry Pi. An interesting little unit, for which I don't see any obvious use cases for myself. As per usual, I will of course be placing an order for one immediately.

This post has been deleted by its author

Old Used Programmer

We Got Use Cases

I laid out some use cases for a Pi3A+...back in April on the Pi Forums. I did overestimate how long it would be before it would be on the market. I guessed 6 to 12 months and it was actually 5 months.

adam 40

My Pi model A is still BNIB, too....

One day, one day...

saif

Naming Standards clearly designed to confuse...

Letters, suffixes and prefixes change from device to device...I can imagine order an A+, and wondering whether I will get the Original A+ or the New A+...costing roughly the same presumably

Anonymous Coward
Anonymous Coward

Re: Naming Standards clearly designed to confuse...

As someone who has a number of poorly named products in his stable, I can say with some authority that naming things in such a way as they won't annoy you, your staff and probably your customers in 15 years when you've significantly changed your product lineup is harder than it first appears.

Generally around the point you're naming it, you're not even sure if anyone will buy it.

Lee D Silver badge

Re: Naming Standards clearly designed to confuse...

Yeah, either name consecutively (1, 2, 3, 4) or have a clear distinguisher (RPi 3+ has more on it but from the same series as the 3 - why do you need A or B AND a plus?).

Otherwise it's gets too tricky.

Basically:

Zero = very tiny one.

Pi 1 = single-core 700MHz, 256Mb/512Mb, composite video (later ones had HDMI - grr!)

Pi 2 = quad-core 900MHz, 1Gb, HDMI

Pi 3 = quad-core 1.2+GHz, 1Gb, HDMI

The + models have more USB / Gigabit Ethernet / faster speeds.

But they really mess it up by randomly changing things between models, including three models of zero, the compute modules, putting pins only on certain models (e.g. the PoE pins?), and changing the form factor and even layout between each one.

It would be much easier to standardise the modules, and just not solder the extra components onto the smaller models, just like every other manufacturer does.

Basically, stick with the highest numbers, largest-lettered model available (RPi 3B+ at the moment) unless you have a particular pressing need to optimise power / space.

Anonymous Coward
Anonymous Coward

Re: Naming Standards clearly designed to confuse...

"unless you have a particular pressing need to optimise power / space"

I think that you will find that the design philosophy behind the Raspberry Pi is just this... a mixture of low power and small size, with improvements along the way so that the models get more powerful or more features. What you get is what they can put in for the targeted low cost.

You don't buy an A+, that is only half of the model number. Many internet sites only offer the latest models.

If you want a small board that does more, buy a different brand of board.

Old Used Programmer

Re: Naming Standards clearly designed to confuse...

Actually...all Pis have had HDMI going back to the original 256MB Model B and Model A.

The confusing point is really the Pi2B as the v1.1 used the BCM2836 and the v1.2 uses the BCM2837. Where the Pi3*+ comes in is the shift to the BCM2837B0 with the flipped silicon and the metal heat spreader...plus the addition of 5GHz WiFi, also under a metal lid.

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