Usb 2 and Usb 3 connectors

[#1]

I have a small problem. I'm trying to add a few extra usb ports to an old pc. The ports on the pc are Type A, USB2. I would need to purchase something like the usb equivalent of a mains extension lead - you know, a cable with a 13A plug at one end and a block with 4-off 13A sockets at the other. In this case the cable would have Type A connector on the end of the cable, and the block would have a few Type A receptacles. The problem is I cannot get them to tell me if the USB connector on the end of the cable is USB2 or USB3. If I buy one of these and it has the USB3 connector at the end of the cable, I believe I can plug it into the USB2 receptacle without damaging anything, but what happens to the extra 5 connections the USB3 connector has - do they cause a problem or are they isolated from the rest of the electronics? Will the extension just work like a USB2 cable? The equipments I would be connecting to the block are all USB2s.

However, I dont know how a USB system works. Would the pc only expect one remote equipment on the receptacle in the pc, so would I have to have only one remote equipment powered up at a time, or can USB cope with multiple equipments under these conditions?

Before anyone rushes to tell me about the difference in speed between USB2 and USB3, I know about that, and it is not a problem. I will live with the equipments running at USB2 speed. Also, I know the block part of the extension cable may need a power supply.

I hope that is clear. Thankyou for any help

[#2]

A 'block of 'USB3' connections plugged into a USB2 port will, in effect, be USB2 and operate as such. So long as the USB port has sufficient power, any equipment on the extension will work - in other words, if you use all the ports on the extension then all devices plugged into the extension will work.

[#3]

@penneck  I have  a 6 port USB3 adapter permanently plugged in to my laptop.  1st usb socket contains a HDTV USB DVB t1  stick, so I can watch tv on my laptop.. ( extension from house aerial cobbled up to the DVB aerial socket) .

Four of the others are filled up with short Android phone charger cables, which charge up some LED strip lights used for "nightlights".  There is a spare/empty USB slot that I use to transfer photos from my camera to the laptop, when needed, or use to download videos from the laptop to another 64GB usb memory stick.. it also has slots for SD cards.

On occasion, I have had three USB memory sticks in the 6 port extender, and they all worked and were showing on the "Devices" list, according to what their descriptions were.  I could transfer to and from any one of them, to or from each other, or via/to or from the laptop, while still watching the TV program.

The only issues I have found with this set up, is that if I am trying to edit a video on the USB stick, the TV pic goes "blocky" and falters. Not a big problem, as I `m obviously working on the video and the tv is not a priority.

One thing I have found is that If i try to access a standby/backup HDD in a caddy behind the laptop.. it HAS TO BE plugged in directly to the laptop, to be able to access it. Probably because of the 5v power requirement on the HDD. Plugging it in to the spare 6th port , it does not get "recognised" or show up on the "Devices" list.
My two USB 2 sockets on the laptop, are permanently engaged , one for the mouse, and the other to run an app.

Similar to this....  https://www.ebay.co.uk/itm/196144585939?    options on the "Select" box for up to 7 slots

[#4]

Hello @jab1  & @shutter . Sorry for the delay in replying to you. Its been a bit hectic here since last night. Nothing serious, just other things had to take top priority.

Thankyou to both of you for your help. Your experience of doing something similar to what I want to do has helped. I just want to clarify a couple of things if I may:-

1. You didn't confirm that the laptop connector is USB2. You did confirm that the adapter is USB3, and I have assumed that meant the flying lead connector was USB3, not the ports on it - just checking and being cautious.

2. You stated that the HD caddy would work if connected directly to the laptop, but didn't work if connected via the adapter. Could the caddy use a separate psu, and if so, would it then work in your adapter. I am just trying to see if there is a solution to that type of problem.

Thanks and have a good weekend

[#5]

@shutter I think the questions above were meant for you. 😀

[#6]

@penneck 

The problem that you have is that USB connectors are only backward compatible, that is, you can plug a USB3 extender in to a USB 2socket. The problem then arises if you try to plug a USB2 cable into the USB 3 output. You will find that these devices are either one or the other, you are unlikely to find devices say USB 3 in and USB 2 out (or vice versa)

There are USB 2 extenders available. For example

https://www.amazon.co.uk/ISOUL-Ultra-Slim-Portable-Expansion-Splitter/dp/B01DYD3Q28/ref=sr_1_17?crid...

USB works like Ethernet switches. You can use all the extender outputs at the same time but note that unpowered extenders have to share the one 0.5A output capability of the source.

[#7]

hello @shutter ,

As a follow up to my earlier reply, I took a look at the adapter that you suggested (the one that was on sale on ebay). I noticed that of the 4 ports, it stated that one was USB3 and three were USB2. As I understand it, USB Rules state that USB3 ports are supposed to be blue, and USB2 ports are supposed to be white. On this adapter, all of the ports are blue. Does this mean that the four ports have the USB3 pin arrangement, but three of them are only wired as USB2? Have the colour rules been changed, or is this manufacturer just ignoring them? Or are all four ports USB3-capable, but the ad doesn't say so?

I'm only asking

Cheers

Graham

[#8]

Everything you need to know about USB https://en.wikipedia.org/wiki/USB

[#9]

@penneck  OK...

1.  the usb port  (used for the 6 port USB adapter)  on the laptop is USB3... the other two are USB 2.

2. The "caddy" i am using is an "ealier type"...  that did not have an enclosure, as such, but had adapters for different HDD pin out configs... so there was no PSU part of it.

The "old" hdd and the connector are permanently "fixed" to the wall behind the laptop screen, by BluTack!.. and the USB lead is located near the USB 3 slot.. ( I woud think the lead is USB2 )

I don`t often have occasion to delve into the "old" hdd, it is just "there" in case it is needed, rather than having to look for it in a drawer of othe HDD`s ! .

3. I suspect that a more modern " enclosure" type of HDD/SSD caddy with a PSU facility, might work, but have no experience of this,

 Regarding your "update"  and the blue and white bit... sorry , but haven`t a clue about that..  I do, vaguely remember reading somewhere, that USB3  was/is supposed to have faster transfer rates, but if USB 2 is plugged in to a USB3 adapter it reverts back to the USB2 speed...  This has never bothered me, or been an issue with how I use them !.

[#10]

@Baldrick1  If I understand your first paragraph correctly, I can plug an extender with a USB3 plug into a USB2 receptacle, but the extender wiill have USB3 ports and I cannot plug USB2 devices or cables into USB3 ports. If that is correct then I need to make sure I buy an extender with all USB2 connectors, that is plug and all ports. However, I suspect that the use of the word 'then' in the second sentence may be a mistake. On the other hand, perhaps USB2 plugs may be able to go into USB3 rece3ptacles, but the extra wires through the extender and required if you want to use USB3 would be isolated because they wouldn't be connected at either end because the extender plug would be in a USB2 receptacle, and the remote device would use a USB2 cable from the extender receptacle to the device (or a USB3 cable which doesn't actually use the extra wires).

When I was looking on the web for extenders, they usually only described the  plug as USB (the picture showed it as Type A), but didn't mention if it was USB2 or USB3. There was at least one that described its plug as USB3, one of its receptacles as USB3 and the rest as USB2, but the picture showed all the receptacles coloured blue. Now my understanding of USB plugs and receptacles as being coloured white if they were USB2 and blue if they were USB3, so I am back to my more recent posts about this, and the various questions I asked about how this could be. So far, nobody has answered those questions. Whatever these answers are, I still need to be cautious when buying anything

Cheers

Graham

[#11]

@penneck I haven't re-read all this topic, but basically, the USB3 plugs will fit USB2 ports, but as the machine (laptop/computer) is only USB2 capable, it will perform at USB2 speeds - but I doubt you would notice any difference.

the USB3 kit is backwards compatible with the USB2 standard - ignore the fact that the ends are different colours.

[#12]

I just install a 2 port usb3 card in my aged HP box.  One of the ports connects to a  powered 4 port  usb3 hub.

PC under the desk, usb hub on top of the desk.........

[#13]

@shutter  Bearing in mind my limited knowledge of USB, and think I can state you are correct about the different speeds of USB2 and USB3. USB3 has extra wiring. What I dont know is how data is actually transferred.

USB2 has two power wires and two data wires, but whether in those data wires, one wire is for transmit from the pc, and the other is receive at the pc, or whether both wires are used for transmit, and the same two wires used for the receive. The latter would require some sort of control/protocol so that both ends dont transmit at the same time and that control/protocol is a mystery to me.

USB3 is even more of a mystery. It has an extra 4 or 5 wires, so my guess is the original two wires are used to transmit, and two of these extra wires are used for receive. What the remaining two wires are for, I have no idea unless they are control wires.

Now having typed all that, quite how a USB3 connection in the pc would work out that the remote device is only USB2, so sets itself up to work as USB2, is lost in a thick fog as far as I am concerned. Nobody who knows any of the above ever seems to make that public.

Cheers

Graham

[#14]

@Champnet - yup that is a possible way round to utilise the extra speed of USB3 - providing you can do the installation/know someone who can...

[#15]

We seem to be meandering away from the original question. As I understand it @penneck just wants more USB2 ports on an old PC with a spare USB2 port.

As such pretty much any old 1:many USB adapter will do the job. USB2/USB3 is irrelevant as they're all plug- and downward-compatible.

The blue ports thing is a red herring, many manufacturers don't follow that "standard" anyway, certainly not consistently.

The only possible limitation, depending what @penneck wants to plug in (as discussed to a degree) is power provision. If multiple devices want to take significant power get a unit with an external power supply.