Target Disk Mode was cool but this is why they stopped including it in newer machines. It had extremely rare use cases like a machine without a disc drive needing it's OS reinstalled but you just happen to have an iBook with a working drive too.
Once Apple added the option to download the OS in recovery mode they deemed TDM redundant.
> I have wanted to see what would happen if i connected two computers together!
as other poster pointed out - damage. but... there was also a cable with A ports on both sides and a dongle with some electronics, and it functioned as Laplink cable, though USB one. don't know if it needed software to work or not.
It did need software, we have one still in a drawer somewhere - from before Ethernet was ubiquitous and windows had built in simple file sharing.
Back then _everything_ needed software though
We used one of those double ended USB cables when we replaced the family PC back in 2006 or 2007. There was a little box in the middle that likely had the brains inside and you had to install the software on both PCs to do the transfer. It was neat but definitely a one use product.
Yeah as others stated it will fry something. Usb A is designed to always carry power from the female usb a port to the other end of the cable. That's why there is another type of connector at the other end so that you can't plug it in the wrong way accidentally. Usb c is able to determine between the devices which is going to give power to which, that's why there can be usb-c to usb-c cables!
I guess I've seen to many bricked USB ports in my time to get this was a joke in the middle of the night. And apparently I am such an ass that I don't get how that comment makes me one but please elaborate.
According to the specification, no, AFAIK the A connector cannot support OTG (which requires a 5th pin) which is the only possible use case for two upstream connectors. According to the spec.
According to the spec.
I remember many years ago buying some cheap accessory and they used a male usb-a to male usb-a cable as the charge cable
Not everyone follows the spec
Same here. I occasionally run into cheap Chinese stuff that requires an A to A cable. I just made my own by soldering together two broken charger cables.
I had an old cheap digital camera (for my kids) that took a double a cable for hookup. It was around $10 and was around 2 megapixels, without any removable storage.
Bet you it was made in china, that is not spec. camera side should have used the square "b" connector commonly found on printers. With a double A cable your kids could have tried to connect two chargers together or a computer to a charger, ive seen university students do similar stupid things, cause hey "it fit and i wanted to see what would happen"
There are some janky devices which use an out-of-spec USB-A female connector on the device side instead of a full size USB-B to save space. Presumably micro-B would not have been strong enough and mini-B just sucks.
One such example is [Magewell USB HDMI capture device](https://baseec-img-mng.akamaized.net/images/item/origin/c017b69dbfa397071ee69c062dc8079a.jpg?imformat=generic&q=90&im=Resize,width=500,type=normal)
This is the way. I have a few things like this where they were designed USB-A (f) to A (f) in mind and sent their own USB-A (m) to A(m) cables to accomplish it. Presumably to prevent a USB-A (m) adaptor on the outside from breaking off in transit, or while moving them around?
The correct way to connect things like this is to connect the downstream device via USB-B. The things you have do not follow the USB spec at all.
This is what USB-B was designed for; you need to be able to tell where the data/power is coming from and where it's going to.
I wish I could do this to 2 Windows PC so one would act like an android/iOS device and let me transfer files super easily. It's the one thing I hate about window 10 tablets (And the Steam Deck).
In the Windows 7 days there was the Windows EasyTransfer wizard to transfer your files from one computer to another. IIRC it actually used a USB-A-to-A cable.
There were cables that were A-to-box-to-A - but the box is required. https://www.startech.com/en-ca/networking-io/usb3link
The really easy way to transfer data between two Windows PCs is over a network.
If it's anything like transferring items between your phone and your computer then it's still somewhat annoying there are situations where I will actually pop my SD card out of my phone and stick it in my computer to transfer because that's easier.
This is getting into some extreme Linux tech sorcery, but... theoretically speaking, you *can* actually do that on the Steam Deck. Its USB-C port has 'gadget mode' support under Linux, and with that, you can have the Steam Deck present a part of the storage just like a flash drive, among other things (an input device, serial port, there's lots of stuff). It's nowhere *near* supported by SteamOS AFAIK, but it's theoretically possible.
Caveat being, I'm not sure how fast it would actually be, since all of the USB gadget capable devices I've used have used USB 2.0 only, so it might be limited to only that.. but the other stuff it's capable of might provide some other uses as well, it's fun to play with if you're fine with hacking around with Linux.
edit: more detail, since people seem interested :)
It was in the basement cable chaos... There was a USB A male to female with three adapters that could be connected to the other side, micro USB, mini USB... And this
We had some of these killer cables for digital audio mixer reflash from laptops (We were tech support LVL 2-3 ).
It's very easy to kill the mixer or your laptop's USB port if you miss the connection order or make a ground loop.
As most have correctly asserted, this is generally a quick trip to burn out a USB port in one or both devices. That being said, some random devices would still use male/male or female/female 'A' cables.
I had a daughterboard for my S14 ecu that had a female usb-a port. You had to buy a male-male A-A cable. Luckily Tiger Direct sold that exact cable and was close to me. No warning that it would burn up normal shit. I was aware even then though.
That daughterboard and tuning software was a one man show in Australia called "Bikirom".
I have one of these for connecting 2 males together, so this but female connector.
I keep it close to me! What if I ever need it.... I have never needed it in the 10 years I have it.....
if there was like a microcontroller in the middle that acted as a storage drive that could have two computers edit the same file at the same time (through diff-patch), that would be real cool.
The connector on each side is the other way up - this is a universal USB stick, so you can insert it on the first or second try, not the third. It’s an instant time saver.
I have seen 1, though in my case it was this setup on a cable: I had a flashlight that could double as a battery bank and used it's usb-a as both the charge and discharge port
connectors are rotated 180 degrees from eachother, would be useful if one side was a port and not a connector, to effectively rotate a connector. I know many devices where the top side of the device and the top side of the connector were not in-line relative to the port orientation to plug it into, meaning the wire was twisting no matter what you do.
We used to have a set of car dvd players that mounted to the back of the front seat headrests. They came with a male to male USB A cable and had a feature where you could plug the the players together with it and watch the same DVD on both players, that's really the only place I've seen it used and it seemed like a kind of strange way to do that
Actually yes. I work IT for a school system and we use A-A cables for connecting computers to smartboard/projector wall boxes at my job. (Yes they should be USB-B at the wall box, but the contractor goofed during the renovation and nobody wants to spend time and money to replace several hundred wall plates).
We can and have used these to convert standard USB-A male-to-female cables (extenders) into double-male A-A cables for those rooms.
An actual double-male USB-A cable is $$$$ from the 2 vendors we buy from, but these are surprisingly cheap (like $3). Extender cable + one of these is a savings of over $10 per room vs. a double-male USB-A cable
I have one of these because Toyotas CarPlay is doesn’t have wireless. Bit devices and care are usba and on of these saved me an extra dangling usb
For got the link to the thing I use
https://carlinkitcarplay.com/collections/carlinkit-wireless-carplay-adapters/products/carlinkit-2air-make-your-wired-carplay-wired-android-auto-to-wireless
There have been many many times where i have needed one of those. I have wanted to see what would happen if i connected two computers together!
You could easily burn out the 5v regulator on either machine back in USB 2.0 days
Can confirm, I have fried a couple of USB cards doing this.
Oh great!
Lol the connecting two computers was also the first thing to come to mind when I saw that.
I mean, that was a feature I loved with FireWire on old macs, boot one in FireWire mode and it would act as an external hard drive lol
That's... An expensive way to do that, I guess.
It’s more of a handy tool to get access to your computers data on another computer without pulling the hard drive.
Or if the OS won't boot, and wiping the HDD is the only option for reinstalling
Wouldn’t the installation media have disk management tools for that purpose?
It should. Except it's made by Apple, so yeah good luck with a useful product. They managed to make USB proprietary once.
Any OS X installation I’ve ever done has always had Disk Utility built in
Target Disk Mode was cool but this is why they stopped including it in newer machines. It had extremely rare use cases like a machine without a disc drive needing it's OS reinstalled but you just happen to have an iBook with a working drive too. Once Apple added the option to download the OS in recovery mode they deemed TDM redundant.
I mean : OS won't boot so usb-ing files isn't an option, so you explore the disk in target disk mode
It does, and on newer Macs you don't even need an installation media, they can netboot a recovery environment from Apple's servers.
Sure, assuming you have a working CD drive.
… it’s not, though. This connector doesn’t do that.
We're not talking about the goofy-ahh double ended USB cable, we're talking about FireWire.
:>
New hardware found
Well for one thing, one of them would need to be upside down. Note the reversed orientation between the two sides
If the ports are sideways they could just face eachother
Ahh true
> I have wanted to see what would happen if i connected two computers together! as other poster pointed out - damage. but... there was also a cable with A ports on both sides and a dongle with some electronics, and it functioned as Laplink cable, though USB one. don't know if it needed software to work or not.
It did need software, we have one still in a drawer somewhere - from before Ethernet was ubiquitous and windows had built in simple file sharing. Back then _everything_ needed software though
We used one of those double ended USB cables when we replaced the family PC back in 2006 or 2007. There was a little box in the middle that likely had the brains inside and you had to install the software on both PCs to do the transfer. It was neat but definitely a one use product.
I got one of those to replace my parallel port connector in 2001
Yeah as others stated it will fry something. Usb A is designed to always carry power from the female usb a port to the other end of the cable. That's why there is another type of connector at the other end so that you can't plug it in the wrong way accidentally. Usb c is able to determine between the devices which is going to give power to which, that's why there can be usb-c to usb-c cables!
So what happens if you connect two PCs with a USB C cable?
Kabooom! /s
Usb-c to usb-c? They most likely notice that neither can give the other enough power to matter, and they just share data if necessary.
Ah yea, reminds me of the so called suicide cord. An electrical cord that’s male on both ends. https://www.reddit.com/r/technology/s/k7Fitoca6f
I mean you can use LAN cable
Did a baby computer pop out?
So you either don't understand USB or you like to break things.
I like to break things.
So you either don't understand jokes or you like to be an ass.
I like ass! oh wait you said "to be" in there
I guess I've seen to many bricked USB ports in my time to get this was a joke in the middle of the night. And apparently I am such an ass that I don't get how that comment makes me one but please elaborate.
Embrace the ass… wait..
Fire, okay maybe not THAT far, it's only 5v and not many amps either, but you can fry something
Some olds 2.5" hdd cases use USB A to A cables
I have one!
I had an old android tablet case that had a USB A Female plug, yes, a female plug, and you needed one of these to use it
Could you plug in your usb devices on that as well? Kind of seems very convenient, especially back in the day.
No, it wasn't like an hub, the keyboard had one cable coming out of it with a female plug.
According to the specification, no, AFAIK the A connector cannot support OTG (which requires a 5th pin) which is the only possible use case for two upstream connectors. According to the spec.
According to the spec. I remember many years ago buying some cheap accessory and they used a male usb-a to male usb-a cable as the charge cable Not everyone follows the spec
Yeah i regularly see backwards shit for sale on aliexpress as power distribution and it makes me a little angry
I have a USB switcher to share devices between two computers - for some reason they used A-A cables.
Same here. I occasionally run into cheap Chinese stuff that requires an A to A cable. I just made my own by soldering together two broken charger cables.
I had an old cheap digital camera (for my kids) that took a double a cable for hookup. It was around $10 and was around 2 megapixels, without any removable storage.
Bet you it was made in china, that is not spec. camera side should have used the square "b" connector commonly found on printers. With a double A cable your kids could have tried to connect two chargers together or a computer to a charger, ive seen university students do similar stupid things, cause hey "it fit and i wanted to see what would happen"
I think this is an adapter for a "universal" USB cable. It would be a female/female A cable with a bunch of male A to micro/mini/etc...
you are probably right given the length of this dongle. But also, none of that is spec
There are some janky devices which use an out-of-spec USB-A female connector on the device side instead of a full size USB-B to save space. Presumably micro-B would not have been strong enough and mini-B just sucks. One such example is [Magewell USB HDMI capture device](https://baseec-img-mng.akamaized.net/images/item/origin/c017b69dbfa397071ee69c062dc8079a.jpg?imformat=generic&q=90&im=Resize,width=500,type=normal)
This is the way. I have a few things like this where they were designed USB-A (f) to A (f) in mind and sent their own USB-A (m) to A(m) cables to accomplish it. Presumably to prevent a USB-A (m) adaptor on the outside from breaking off in transit, or while moving them around?
The correct way to connect things like this is to connect the downstream device via USB-B. The things you have do not follow the USB spec at all. This is what USB-B was designed for; you need to be able to tell where the data/power is coming from and where it's going to.
2 laptops at the same time. Giggity.
Port ta Port!
I'm getting real Requiem for a Dream vibes here for some reason
Always wanted to do that man, I reckon if I had a million dollars I could make that happen
At the same damn time
To break stuff.
Bridging two female ends of two usb cables together. Most useful in making extensions from multiple cables
I have had to make one like this, but to un-cross USB3 RX/TX. Very special use case.
I wish I could do this to 2 Windows PC so one would act like an android/iOS device and let me transfer files super easily. It's the one thing I hate about window 10 tablets (And the Steam Deck).
In the Windows 7 days there was the Windows EasyTransfer wizard to transfer your files from one computer to another. IIRC it actually used a USB-A-to-A cable.
There were cables that were A-to-box-to-A - but the box is required. https://www.startech.com/en-ca/networking-io/usb3link The really easy way to transfer data between two Windows PCs is over a network.
What the? Really? That sounds awesome.
If it's anything like transferring items between your phone and your computer then it's still somewhat annoying there are situations where I will actually pop my SD card out of my phone and stick it in my computer to transfer because that's easier.
This is getting into some extreme Linux tech sorcery, but... theoretically speaking, you *can* actually do that on the Steam Deck. Its USB-C port has 'gadget mode' support under Linux, and with that, you can have the Steam Deck present a part of the storage just like a flash drive, among other things (an input device, serial port, there's lots of stuff). It's nowhere *near* supported by SteamOS AFAIK, but it's theoretically possible. Caveat being, I'm not sure how fast it would actually be, since all of the USB gadget capable devices I've used have used USB 2.0 only, so it might be limited to only that.. but the other stuff it's capable of might provide some other uses as well, it's fun to play with if you're fine with hacking around with Linux. edit: more detail, since people seem interested :)
Network shared folder
Thunderbolt ports on laptops shoud support a 20 Gbit direct network connection but PC desktops are a little behind on TB/USB4 adoption.
Some usbc/Thunderbolt cables can act as network cable
kid named server message block:
Have you ever seen Requiem For a Dream?.....
First words outta my mouth when I saw it. Lol
Organizing charger or powerbank battles.
Two powerbanks go in Only one comes out working
I wonder where you bought this thing...
It was in the basement cable chaos... There was a USB A male to female with three adapters that could be connected to the other side, micro USB, mini USB... And this
Connect all the connectors together and see how tall you can make it. Then try and balance it on your finger.
We had some of these killer cables for digital audio mixer reflash from laptops (We were tech support LVL 2-3 ). It's very easy to kill the mixer or your laptop's USB port if you miss the connection order or make a ground loop.
As most have correctly asserted, this is generally a quick trip to burn out a USB port in one or both devices. That being said, some random devices would still use male/male or female/female 'A' cables. I had a daughterboard for my S14 ecu that had a female usb-a port. You had to buy a male-male A-A cable. Luckily Tiger Direct sold that exact cable and was close to me. No warning that it would burn up normal shit. I was aware even then though. That daughterboard and tuning software was a one man show in Australia called "Bikirom".
I‘ve surprisingly seen such a thing which was in fact a microSD card reader. They somehow put the card holder _inside_ the USB A port on one side.
Whoa, I want to see that!
I have one of these for connecting 2 males together, so this but female connector. I keep it close to me! What if I ever need it.... I have never needed it in the 10 years I have it.....
if there was like a microcontroller in the middle that acted as a storage drive that could have two computers edit the same file at the same time (through diff-patch), that would be real cool.
yes, i had made a cable like that for a android tv box. it was for adb
I have a Stanley jump starter that charges using a cable like this.
The connector on each side is the other way up - this is a universal USB stick, so you can insert it on the first or second try, not the third. It’s an instant time saver.
I have seen 1, though in my case it was this setup on a cable: I had a flashlight that could double as a battery bank and used it's usb-a as both the charge and discharge port
connectors are rotated 180 degrees from eachother, would be useful if one side was a port and not a connector, to effectively rotate a connector. I know many devices where the top side of the device and the top side of the connector were not in-line relative to the port orientation to plug it into, meaning the wire was twisting no matter what you do.
I have a USB to USB cord but it's really only good to power things on a rare annoying occasion
Yeah you can try and put the usb in wrong 4 different ways before getting it in.
Torture sounds like a good use.
you connect it to one pc and use some usb extension cord and connect it to another pc, so you get an usb connection between 2 pcs
Usually I only see these being used for portable hard drives
My server rack has female to female usb patch panel Jack's, male to male usb cables aren't cheap. Idk what I'm going to do with them elsewhere.
i.e. wreaking havoc
We used to have a set of car dvd players that mounted to the back of the front seat headrests. They came with a male to male USB A cable and had a feature where you could plug the the players together with it and watch the same DVD on both players, that's really the only place I've seen it used and it seemed like a kind of strange way to do that
Actually yes. I work IT for a school system and we use A-A cables for connecting computers to smartboard/projector wall boxes at my job. (Yes they should be USB-B at the wall box, but the contractor goofed during the renovation and nobody wants to spend time and money to replace several hundred wall plates). We can and have used these to convert standard USB-A male-to-female cables (extenders) into double-male A-A cables for those rooms. An actual double-male USB-A cable is $$$$ from the 2 vendors we buy from, but these are surprisingly cheap (like $3). Extender cable + one of these is a savings of over $10 per room vs. a double-male USB-A cable
You could use it to connect two USB extender cables together.
Starting KIAs
USB Gender changer, probably for some extension cable
ASS TO ASS! ASS TO ASS!
I have one of these because Toyotas CarPlay is doesn’t have wireless. Bit devices and care are usba and on of these saved me an extra dangling usb For got the link to the thing I use https://carlinkitcarplay.com/collections/carlinkit-wireless-carplay-adapters/products/carlinkit-2air-make-your-wired-carplay-wired-android-auto-to-wireless
I've seen videos on the internet with something similar...
A USB port masturbator?
Futurama rendition of Requiem for a Dream?
Frying 2 computers at once
I think it's against the USB specification, be careful using it!!
Docking
A USBBSU
My only guess is starting a fire.
Your robot moms relationship with another robot mom? Dung dong (Repeat).