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Barrier: Share mouse and keyboard between computers

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Re: Barrier: Share mouse and keyboard between computers

#101

Post by loxias »

spicybright wrote: post #70
wyager wrote: post #66

Earlier quoted context omitted.

> It should just be a switch, no complex electronics For any high-bandwidth thing like HDMI, you need to do clock recovery and copy over the bitstream at the very least. You can't just use relays or whatever. Doing this at 10gbps+ is going to cost a bit.

I don't see that much of a reason you can't do a relay to "disconnect" one hdmi and plug in another. The computers would see the HDMI cable/USB cords unplugging and re-plugging. Obviously this can be problematic, but I can't see it being that expensive.

Spend just 5 minutes on the Wikipedia page for HDMI and you'll see how much of a folly this would be. :)

It has like... 4? different physical layers running at different speeds and all sorts of other weirdness.

Re: Barrier: Share mouse and keyboard between computers

#102

Post by loxias »

zanecodes wrote: post #39

I can't install Barrier on my work laptop for policy reasons, but I don't want to buy a KVM, so a project I've been interested in building when I have time is porting enough of the Barrier/Synergy protocol to the Particle Photon [1] or BeagleBone Black [2] I've had lying around for a while, and then configuring it to emulate a keyboard and mouse via its USB gadget driver, allowing it to control my work laptop over US…

I'm not entirely sure I see what your describing with certainty, but are you talking about essentially a "barrier client appliance?" A dongle you plug into all the machines you want to control using barrier, which connects wirelessly to the barrier server daemon running on your main computer?

If so, neat idea, and I've done stuff like that before. You can even have the client appliances be configuration free -- they announce themselves to the network and the server pushes out after pairing.

Interesting and fun to build, but I don't quite see the use of such a thing. It would still require running the barrier server on your laptop. I'd try to possibly go a different direction: A cheap device (RP2040 based?) that sits in between an external keyboard and your laptop. Other copies of the same hardware plug into the usb ports of other computers you'd wish to control.

Re: Barrier: Share mouse and keyboard between computers

#103

Post by loxias »

zanecodes wrote: post #61
avidiax wrote: post #53

Earlier quoted context omitted.

The annoying/challenging part is that you need to drive the 2nd machine using relative motions, but place the cursor accurately and keep track of it. If the 2nd OS skips frames or has acceleration, you are pretty quickly implementing a Kalman filter.

According to the Particle Photon docs [1] it's actually capable of moving the mouse to absolute coordinates, but I haven't tried that yet. [1] https://docs.particle.io/reference/device-os/firmware/#movet...

It's been a while since I was deep in the guts of implementing USB HID devices, but I think you can specify in the descriptor if you're sending relative or absolute values.

There's a rewarding UX that can be made by switching the touchscreen to relative instead of absolute, you get more fine grained control.

Re: Barrier: Share mouse and keyboard between computers

#104

Post by octobus2021 »

mwexler wrote: post #9

This still requires a dedicated monitor connection to each box with a hardware or source switch, right? Or a screen per device? That is, the KVM (in the VGA days) used to switch the mouse, keyboard, and video source so a single monitor, keyboard, and mouse switches across devices. But barrier doesn't try to solve that part, I think. Modern HDMI KVM hardware switches seem rather expensive; anyone found a good way to "…

Depends on your price range I guess. You can find iogear/belkin HDMI 4 port switches for a bit under $100. Generic ones will be even less (maybe even around $50). I personally use DVI KVM from iogear (GCS1104) which cost me about $130, one of my machines is a gaming rig with Nvidia card and it works flawlessly.

Re: Barrier: Share mouse and keyboard between computers

#105

Post by bradknowles »

zackmorris wrote: post #56

Barrier looks great, but does anyone know why KVM switches with DisplayPort or HDMI are so outrageously expensive? It should just be a switch, no complex electronics, so I truly can't figure out why any KVM should cost more than say $30-50 US. I suspect DRM or patents for rent seekers are involved somehow. Or maybe they're playing on the naivety of the business community towards this stuff. I'd sure like to know, and…

You should ask the guys at Level1 Techs. They supposedly make the best DisplayPort KVMs in the business.

Re: Barrier: Share mouse and keyboard between computers

#106

Post by loxias »

1MachineElf wrote: post #79
zanecodes wrote: post #39

I can't install Barrier on my work laptop for policy reasons, but I don't want to buy a KVM, so a project I've been interested in building when I have time is porting enough of the Barrier/Synergy protocol to the Particle Photon [1] or BeagleBone Black [2] I've had lying around for a while, and then configuring it to emulate a keyboard and mouse via its USB gadget driver, allowing it to control my work laptop over US…

I would love more projects like this, especially ones that utilize the BBB. Personally I've had the same need (shared keyboard and mouse) and same requirement (work policy preventing additional software) for many years now so have resorted to using a KM switch (no V) bought off eBay. If you look up "KM switch", the first thing you'll notice is that most search engines will automatically assume you meant "KVM switch"…

> The problem is that people with the skills and people with the motivation haven't overlapped in a significant way.

Yeah... I, uh, have the skills (and I'm guessing you do too), but I don't see the point of the product. But you're right, a KM switch could be made very inexpensively. Could also be made modular, and wireless (for people who are into that thing).

You don't even need heterogeneous nodes, I think. All the nodes could be the same -- an RP2040 (now my favorite microcontroller for personal projects) can handle being a USB device, and host. The nodes could connect to each other through a daisy chained i2c, with another layer above for autoconfig.

What would be a price people would pay for such a thing? Say, 1 control node and 3 client nodes (allowing you to control 4 computers with 1 keyboard and mouse)? You say under $100 is rare?

Re: Barrier: Share mouse and keyboard between computers

#107

Post by superdug »

checker659 wrote: post #50

Just an FYI for mac users: Universal Control is a native macOS alternative to barrier that's about to debut with macOS 12.3 (currently in beta). As an ex-synergy user, let me just say how awesome the implementation is. What's crazy is you can share your mouse and keyboard not only between two or more macs but also between your mac and an iPad (if you have one, obviously). And the latency is crazy unnoticably low (eve…

I've noticed that this doesn't _always_ work. Sometimes I just mash my mouse into the side of my screen and never get on to my iPad. So I've just switched to Logitech bluetooth mouse and keyboard. It's easier than a KVM and more reliable than software.

Re: Barrier: Share mouse and keyboard between computers

#108

Post by sokoloff »

dividedbyzero wrote: post #71
parentheses wrote: post #67

Earlier quoted context omitted.

IMO KVM Switches with display support are luxury items. Who has 2 computers? People who can afford them.

I didn't pay for my second computer, work did.

Work paid for my DP/USB KVM as well… That fits the same pattern that GP implies.

Re: Barrier: Share mouse and keyboard between computers

#109

Post by zanecodes »

loxias wrote: post #102
zanecodes wrote: post #39

I can't install Barrier on my work laptop for policy reasons, but I don't want to buy a KVM, so a project I've been interested in building when I have time is porting enough of the Barrier/Synergy protocol to the Particle Photon [1] or BeagleBone Black [2] I've had lying around for a while, and then configuring it to emulate a keyboard and mouse via its USB gadget driver, allowing it to control my work laptop over US…

I'm not entirely sure I see what your describing with certainty, but are you talking about essentially a "barrier client appliance?" A dongle you plug into all the machines you want to control using barrier, which connects wirelessly to the barrier server daemon running on your main computer? If so, neat idea, and I've done stuff like that before. You can even have the client appliances be configuration free -- they…

More or less, but in my case I would only have to run the barrier server on my personal desktop, and won't have to install any software on the client I wish to control (in this case, my work laptop). I'd like to piggyback off of the existing Barrier code, since I already use Barrier to control my personal Surface Pro, which also sits on my desk.

I really wish my 49" Samsung Odyssey G9 supported DDC over DisplayPort, so I could also switch my monitor input via software, and essentially have a KVM without buying any additional hardware.

A major consideration for me is avoiding introducing any extra input latency between my input/output devices and my personal desktop, since I use it for gaming. I'm okay with trading off additional latency when controlling my work laptop in exchange for lower latency on my main desktop. That said, I may end up using my BeagleBone rather than my Photon, since it has an ethernet port, and running Linux may prove advantageous.

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