Bin half-baked Raspberry Pi hubs, says Pimoroni: Try our upper-crust kit Raspberry Pi accessory specialist Pimoroni reckons it has the answer to one of the tiny ARM-based computer’s signal limitations: too few USB ports for all the add-ons you might want to hook up to it. Pi users have dealt with only having a pair of USB 2.0 ports - there's only one on the cheapest, the Model A Pi - by connecting …
This has been problem plaguing USB hubs and USB devices far before the Pi arrived. I have a number of computers backing up to portable/bus powered USB hard-disks - and after a few months of use a lot of them start to conk out in the middle of a multi-hour data transfer. The solution for me was a Targus USB 2.0 4 port desktop hub. This particular model (you can find it on Amazon - not sure if allowed to post links to products here) has two out of the 4 ports which provide 1 full Amp of power. This might be outside of the USB spec (500mAh) - but it certainly gets around the problem that some devices (specially bus powered portable hard-drives) need just slightly more power than the spec allows for - specially as they get a bit older and during prolonged data transfer sessions. No more problems for over a 1.5 years now and about 15 usb hard-disks and 4-5 hubs involved.
There are loads of options available. Best for a desktop machine is to buy a powered USB 3 hub (they are backwards compatible). Those have 12 v input and often have better equipped power supply's. Anker (pricy) or Orica (Anker in generic clothing) have 10 port ones with 5 amp supplies. Unfortunately the Pi does not see these but el cheapo generic ones are available on ebay
Most hubs assume you will never take full power which is why there are 7 port ones with 1.5 amp PSU's as they assume devices plugged in will be lower powered (keyboard/mice) or self powered (external HDD). Also you can check your motherboard's USB panel connector specs, my old gigabyte board has an internal port that supplies extra power "for rapid device charging" and front panel ports are dirt cheap.
That still leaves the question if they are capable of providing more than 500mA *per* port to USB 2.0 devices. Just having a decent power supply might not be enough - if they stick to the official USB 2.0 spec - in some cases.
I can't work out so far from reading around if USB 3.0 hubs will offer 0.9A power to all devices connected to them - or only if they are detected as USB 3.0 devices - to keep within the spec?
Indeed, Belkin has also advertised one their hubs as being multi TT capable, they termed it 'turbo transaction translator technology'. I've used this model exclusively on a number of PCs/external device combinations for years without any issues.
It's not something that many manufacturers highlight so I've worked out out whether it's ubiquitous or the exception.
Seconded - It's what I use - faultlessly. Powers the Pi, HDD, USB stick and WiFi. Tried to find the model on the Targus site with no luck - maybe discontinued? Found on eBay uk, but didn't see it on Amazon.
Anyway, it's this one.
http://tinyurl.com/q38g7hb
But I'll order the Pimoroni version, as I think the Targus uses a single TT thingy -from the manual "Do not data to or from multiple hs devices such as camera and scanner at the same time." (and it's a bit of a fugly ucker, so it's hidden best as I can)
> one of the tiny ARM-based computer’s signal limitations: too few USB ports
In my experience, the number of USB ports on the Pi is a small matter. Ther are other design points that are more important to improve.
If anyone was planning on designing a "model C", I'd suggest dumping the Ethernet port, in favour of a Wifi device. Moving the ports around so they don't come out of all sides (possibly start by changing the SD card for a micro-SD), thus making it easier to integrate into other equipment. Adding some onboard flash, to obviate the need for an external card - though keeping the option for one.
It would also be nice if the board had (at least) a reset button, or, better, a header to break one out to a front panel. Do the same for some user addressable LEDs, so that the embedded version of "Hello World" doesn't need any hardware hacking and add an audio input port and you'd get to compete with the current best hobby SBC products like Cubieboard-2 and Olimex's A13
Could they supply it without one but with the chipset still included so people can solder/clip one on?
Although I feel having a tiny computer which is smaller than all the bits you glue on to make it usable suggests you should perhaps have bought something a bit more complete in the first place!
25GBP was their problem.
Ethernet is super cheap, Wifi not so much. Also Ethernet is universal worldwide Wifi has different power levels/channels depending on region so it would have been a real pain having to produce more and get appropriate certification approval (they had approval issues with the current model)
Moving the ports around so they don't come out of all sides
If only there was a standard to define board size, port locations and mounting screw points so that there was a readily available supply of cases etc that the RP gould fit into .... micro/pico/nanoITX anyone?
Erm many of your design points don't actually make sense. All ports on one side? Not physically possible without larger board and the intent was to cost reduce. On card flash removes the convenience of being able to just pull & replace the OS without faff. Reset button, header is present in later revisions. User addressable leds? Why waste those GPIOs + add cost? It's trivial to add what you prefer without dictating. Similarly wlan vs ethernet, buy a model A and add wifi dongle. No audio input? Come on.
You're forgetting/ignoring RPi was designed for a specific purpose - not necessarily matching your desires or the feature set of other SBCs. Cheap & educational and easily replaced. It does the trick. If you want "better" there's plenty of alternatives, stuff based on far more powerful ARM cores etc.
> You're forgetting/ignoring RPi was designed for a specific purpose
Nope, nothing forgotten here. It's important to understand that this is a suggestion for a model C (per. the post) and not as a replacement / substitute for the existing boards.
Since the hardware is open source, there is scope (though nobody has taken it up yet) for any other manufacturer to produce the current board or any future improved Pi - even with their own custom additions. As it is, pretty much all the later hobbyist SBCs have gone for bigger, better, faster processors and beefed up I-O, memory and facitilites. While the Model-B fills a niche, you'd kinda home the original developers weren't resting on their laurels and had some plans for a refresh.
>Nope, nothing forgotten here. It's important to understand that this is a suggestion for a model C (per. the post) and not as a replacement / substitute for the existing boards.
I think you will find that any possible model C, (which is a long, long way off,) will be addressing the same market as the model B. The Raspberry Pi is fantastic as a hobbyist computer, but that is not what it is designed as. It is designed as a cheap computer for kids. None of your suggestions are good ideas in that context.
Ethernet is fast, easy and foolproof. Not so WiFi. In a school environment, you need to be sure everyone is connected to the right network. WiFi would also increase the cost.
Any change in the layout to move connectors would increase the cost because the board would have to grow.
IIRC, Micro SD was considered, and it was found that the sockets were of insufficient quality. I would prefer a full-depth metal socket, but that probably comes down to cost too.
Having all the OS on exchangeable SD is what makes the RaspPi work in an educational setting. It is impossible to brick it.
Actually, the point about the port layout if VERY pertinent - with ports on all four sides, designing a case for one of these is VERY limiting, and has almost no affect on cost - if the PCB was twice as big, the component cost would rise by less than a quid.
Funnily enough, that was my first thought about this hub - why didn't they design it to also be a case for the Pi?
You could be right. Overall though, it does the job for me as it is. It would be nice for some backups to complete more quickly, but it's not that important. My laptop connects in via VPN so it's often doing it over 3G anyway.
New revisions of the Pi are likely to cover more connectivity options, higher power etc. but only if doing so doesn't affect the price too much. It is what it is.
Actually, you havent described problems - you've just described a different feature set you'd like on a Model C.
Not having wifi? Not actually problem. (USB Wifi stick)
Not having a reset switch? Not a problem. (Pull the plug out, or use GPIO)
etc
As for uSD - easy to lose, slots are more fragile, and more expensive.
And no, they are not resting on their laurels, but it's important to keep a stable platform for the intended market.
It's not just RasPis which suffer from MicroSD failings, but at least you can solve the issue on those by pulling out the other end.
I'm fairly careful, but my phone's MicroSd power socket is unreliable after 2 years. Time to fit a new one.
I suspect the the EU made a mistake in specifying them as a standard power connector, but it's strongly motivated me to ensure the next phone has contactless charging onboard.
>I'd suggest dumping the Ethernet port, in favour of a Wifi device.
Disagree. To expensive & specific. Mini PCI socket, on the other hand would be superb: Fit a nice MIMO WiFi card if you like to create a beast of a home AP/router/server or fit something else for other projects or leave it empty and save yourself the dosh... Of course an AP/router would still NEED ethernet. PoE would be a nifty addition.
>Adding some onboard flash, to obviate the need for an external card - though keeping the option for one.
Completely disagree there too. Why ADD to the cost of the thing? It's SUPPOSED to be AS CHEAP AS POSSIBLE!... how about a PAIR of micro SD slots? Methinks that'd be even nicer while NOT recklessly inflating the cost. In a similar vein, how about an empty EEPROM socket? If you have a need specifically for onboard storage.
A big fat NO to onboard flash. The beauty of the thing is that it's practically impossible to brick it from software. If you corrupt the card, take it out and reflash it on another machine, and voila, unbricked.
Can't do that with onboard flash, unless you can make it check if the external SD is bootable and boot from that, before attempting to boot from the onboard flash (still leaving onboard visible as a block device to the external-booted OS)
SD for micro-SD? Second of my purchases/addons: an Adafruit micro-sd adapter. Does still stick out a bit, but offset by the fact the micro-SD can be taken out with the case on. Others - the micro-SD comes out from the side. Yep, the Pi's Achilles heel.
The first of my purchases? Some replacement SD connectors*. Mine broke on scond insertion, warranty replacement exactly the same. Held with a piece of broken credit card carefully glued on top of the socket (the embossed numbers giving exactly the right amount of downforce)
*ebay, search 'alienspec'.
But no Ethernet? No go on that one, mate! Wireless router app, for a start!
I like it, it's a really good idea. Nice design for the kids, bright and fun and that's where to be honest it becomes a slight problem for me. I love the fact that it's "proper" USB and that you can power a Pi from it so negating the need of buying a separate PSU for it.
Personally I'm not a great fan of USB hubs (or almost any device) that has cables spewing out of it at all angles. My latent OCD kicks in when it comes to cable management I'm afraid, I like to see cables all heading in roughly the same direction. It would be great to see a second version of this cased in a normal rectangular type box that would be easy to mount alongside (or on top of) a normally cased Pi. Yes I know that due to PCB/tooling costs this is very unlikely to happen and it is a fairly minor gripe.
Anyway it should look great on a desk in a computer lab in a school, which I guess is it's primary target. So good luck to them and I hope they sell shed loads
Pity the EU hasn't 'aligned' power connectors.
Think this has been considered but as for competition reason the standard would have to differ from all existing plugs (to avoid any country/region getting unfair advantage) then its not been considered feasible.
UK ringmain designs effectively mandate the use of fused plugs or individually fused outlets, but there's NO compelling reason to use rainmains in new builds or rewires (extra labour costs far outweigh a few pence saving in copper)
It might be possible to standardise on C12/C13 and C19/C20 but that would take a lot of politicking I certainly wouldn't want to get into when pretty much all the EU is using or moving to variants of Schukos and the UK is the odd man out.
FWIW the contact pressure and surface area in the UK plug is lower than in most countries, resulting in a higher possibility of socket thermal damage when the pins are subjected to overcurrent conditions - which is partly why the thing got scaled up to ensure "overcurrent" would blow the fuse first.
(Round pins are also a bitch to deal with in terms of contact pressure as it's difficult to get 100% mating in mass produced brass components which in turn means the contacts can have hotspots and end up desprung. Blade type pins (USA/AU/NZ/China, etc) are easier to fabricate, make reliable sockets for and have more consistent contact pressure, but it hurts like hell if you stand on one in the middle of the night. They can also have pin shrouds - AU/NZ plugs have had these for about a decade)
Ring mains solve quite a few problems compared to radials or spurs in a domestic environment.
Much higher current available at a double (or triple) socket (kettle plus microwave at the same double socket), and no marshalling or junction boxes needed to join any number of sockets to a single fuse/RCBO/MCB at the fuse box/DB, as there will only ever be two cables at each join.
Construction is the same really, just pull the cable along the route and back, with a loop of spare at each socket, and if a run is hard, just cut at a socket and pull that run direct, same as for radials and spurs.
Not sure what you mean by "shrouded", but sleeved L&N pins have been a requirement on both BS1363 and BS546 since 1984, making it safe to slide child fingers behind the plug while it's being inserted and removed.
I've also not seen a BS1363 socket damaged by overload except when a fake (or wrong/no) fuse had been fitted.
That said, the "stackabilty" of the NZ/AUS plugs is rather nice and avoids a problem faced elsewhere.
Many UK multi-way adapters are actually rated at 6A or 10A total, making them annoying and sometimes dangerous as people may refit the wrong fuse after overloading them.
Yup,
While others might be smaller, we only need ONE type of plug, no matter what the amperage of the device!
I had to swap over plugs myself in a flat once, they had installed the wrong kind for my cooker, even when they KNEW it was supposed to be a higher amperage socket!
But standing on a UK plug won't break it. You have to drop them quite a long way onto a hard surface to damage them.
Standing on any of the myriad of EU plugs may break it, standing on a NZ/AUS plug will probably break it, and looking vaguely in the direction of a US Edison plug will shatter it into a myriad of pieces.
And no, there's no such thing as a standard EU mainland plug anyway. The only thing that's common across most of the EU is the approximate location and rough size of the two Live/Neutral pins.
Spain and France (CEE 7/5) are round and have a female PE off-centre, Germany (CEE 7/4) are round and use clips at the top/bottom, Denmark has a half-round PE, Switzerland (not EU but close) are roughly diamon-shaped with a round PE off-center, while Italian plugs (CEI 23-16) put the PE exactly in the middle and come in two nearly-identical but incompatible sizes, neither of which quite match anything else. Multi-standard sockets that meet CEE 7/4 as well as CEI 23-16 are getting common the Italy.
It's only physically possible to get a CEE 7/7 plug that correctly fits German and French (CEE 7/4 and 7/5) sockets. All the others are incompatible due to the impossibility of getting the Protective Earth.
The closest thing to an "EU mainland plug" is the un-earthed CEE 7/16 - which isn't a safe way of powering anything other than Class II equipment, and doesn't work in Italy.
In summary - everybody should use either B1363 or BS546 plugs and sockets, because those are by far the best ever invented.
>But standing on a UK plug won't break it. You have to drop them quite a long way onto a hard surface to damage them.
I wasn't talking about breaking the plug. In the battle of foot vs plug, foot is going to lose, and it's going to f*****g hurt too.
Indeed! Your post reminds me of this tongue-in-cheek review of various AC plugs in use around the world. It has a nice swipe at the Euro habit of trying to standardise things too.
I use one pi (old model B) headless for my tinkering and a new model B as a media system. It pulls media over ethernet and I have a wireless keyboard/mouse combi. This leaves a spare USB if ever I decide to use it.
I do like the look of this port device though. The pi seems to have brought people together with ideas of good (and working well) kit as well as aesthetics. Providing a board with components on it seems to have had a good effect on people and brought out a lot of creativity.
Initially just with a KB/M hooked upto the onboard ports and the whole thing running off an underpowered wall wart. Solved that with a powered hub (1 amp) then got myself an external 2.5'' HDD that was playing a bit fast and loose with the USB spec.
After half a dozen solutions I ended up using my samsung tab charger and an A - B usb lead to inject power into the bus and get the whole lot spinning. I really don't like the way that if there is any power on the USB bus, the Pi will keep running, regardless of the state of its power socket, just seems shoddy.
The review on the Raspberry Pi site states that this hub *won't* back power the Pi through the USB port when using the downlink (A->B cable) port. This is unlike pretty much all the hubs I've encountered or others have discussed.
This "feature" (behaving correctly) may be what makes this hub actually worth what it costs.
In addition, the 1A port that can be used to power the Pi puts out 5.2V, very similar to the Adafruit 5.25 1A power supply. This design compensates for the very low quality power cables so many people seem to use.
Although, I'll need to find a compatible 3A supply with a US plug... I suspect that Adafruit will probably come up with one.
Was most interested in Pi when announced 2 years ago, but seem to recall reading it not aimed at, and did not handle well high bit-rate 1080p MKVs with hi-fidelity audio. Read its CPU, being a previous generation to ARM7, was too weak to run heavyweight Linuxes like Ubuntu.
For a Model C, I would like a design capable of being a sink for streaming all qualities of multimedia, from just HiFi to Active Speakers, to hi bit-rate 1080p MKVs to HDMI, using more current SoC, eg Snapdragon 600/800 or Tegra4, 4xUSB to reduce need for hubs, left-right audio-out brought out to headers to allow adding better sockets i.e. RCA, as already suggested, a miniPCIe socket to allow a decent WiFi card with good antenna, an internal socket for expandable flash.
Does anyone know of a device like this available now ?
Back-feeding 5 volts into the Raspberry Pi via its USB port is not a feature, it's a bug.
It means that the subject USB hub has left off the special, low voltage drop, Schottky diode that should be used to allow the host to power the hub while preventing the hub from powering the host. That spot on the PCB has been jumpered.
The problem to be prevented with the diode is the situation where the host (perhaps not a Raspberry Pi, or perhaps a combination of gadgets) requires some arbitrary amount of current that's just enough to cause intermittent problems (low voltage at the host) but not enought to be the obvious cause. Recipe for frustration.
The only reason to leave off this "expensive" Schottky diode is to save a couple cents on the BOM.
I bought a USB Hub from a famous online vendor based in Hong Kong with the name starting with DX and ending with .com. It was about $8 (shipped!) and has ten (!) ports. It had the same missing diode cheapskate short-cut. I cut an internal trace in the cheap hub to isolate the power supplies. It now *requires* the included AC adapter, but at least I don't have to worry about sharing power in a manner that will not help with reliability of the Rasoberry Pi in outlying cases where the current is creeping up to the ill-defined trouble point.
Nice Raspberry Pi logo on the reviewed USB Hub though. Full credit for style.
Wouldn't it have been a good idea to add a USB socket or an extra micro USB cable coming out of the PiHub's power supply so you can directly power the Pi without losing a port on the USB hub or having to use a separate adapter - as this is being marketed to use with the Pi?
Also, making it a Pi case would also be a winner, so four additional USB ports below the Pi board, holding the board in place by taking the lower USB socket.
I hope its better then the NewLink one that was listed as 'compatible' with the pi.
I got one of those as they were touted as the best USB powered hub for the pi.
I am running a 1 wire temp sensor network, Webcam and external SSD, it ran this setup for a month before refusing the power the SSD, I replaced SSD and external caddy, no joy, just refuses to run it now. (power LED flashes continuously on, SSD, Hub and Pi! works fine in pc. I guess 2A isn't enough to power this lot! Lets hope 3A1 is, a PiHUB is now on order.
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