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Barrier: Share mouse and keyboard between computers

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Re: Barrier: Share mouse and keyboard between computers

#81

Post by bartvk »

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.

As soon as there's enough volume for someone to design a specialized IC (and reference PCB), and it gets produced by VIA or TI or whatever, sure, then it's neither a problem nor expensive.

Re: Barrier: Share mouse and keyboard between computers

#82

Post by Nextgrid »

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.

Shielding might be a problem. You need your switching circuitry (which is most likely going to be solid state rather than individual relays for each line) to be equivalent to a good cable in terms of interference, crosstalk, etc.

Re: Barrier: Share mouse and keyboard between computers

#83

Post by zamadatix »

ballenf wrote: post #80

Anyone else ever wanted multiple cursors and multiple mice on one computer? Sometimes I'd rather move my hand to a different mouse than drag the cursor across all that screen real estate. Also the different pointers would stay put when not in use.

I'm not sure about multiple cursors but for the large screen real estate problem some mice have a "precision" button that changes the DPI which can be leveraged. The intent is to make the DPI much lower while pressed (or toggled depending) but many allow you to set what DPI value you want it to use directly. This allows you to specify that the mouse will move say 4x as fast while you hold the precision button which is a lot less hand movement and coordination than switching over to another mouse.

Basically manual static acceleration for those that hate automatic smooth acceleration but want to occasional move fast easily.

Alternatively if you're lucky enough to have reasonably steady hands you'd be surprised what you can get used to as a default static speed. My multi-monitor setup is over 70 inches horizontally but I can get across it in a flick or still move pixel by pixel if I want.

Re: Barrier: Share mouse and keyboard between computers

#84

Post by peeters »

ballenf wrote: post #80

Anyone else ever wanted multiple cursors and multiple mice on one computer? Sometimes I'd rather move my hand to a different mouse than drag the cursor across all that screen real estate. Also the different pointers would stay put when not in use.

I've done that for paired programming, it was a decade ago, but IIRC Xorg made it pretty easy to set up. That said...do not recommend :). It's too jarring.

Re: Barrier: Share mouse and keyboard between computers

#85

Post by makomk »

wyager wrote: post #66
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…

> 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.

There are really cheap commodity ICs that can switch HDMI, and they're generally purely analog devices that don't bother trying to reclock the signal. The real reason is that KVMs are specialised devices with a niche market. (Though there does seem to have been a bit of a push to integrate limited KVM functionality into some monitors lately.)

Re: Barrier: Share mouse and keyboard between computers

#86

Post by Mindless2112 »

ballenf wrote: post #80

Anyone else ever wanted multiple cursors and multiple mice on one computer? Sometimes I'd rather move my hand to a different mouse than drag the cursor across all that screen real estate. Also the different pointers would stay put when not in use.

EitherMouse[1] can do multiple pointers on Windows.

[1] https://eithermouse.com/

Re: Barrier: Share mouse and keyboard between computers

#87

Post by wyager »

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.

Because mechanical relays have high impedance at HDMI frequencies.

Re: Barrier: Share mouse and keyboard between computers

#88

Post by muwtyhg »

uoaei wrote: post #42

Any tool that switches screens, too? Essentially one terminal for n computers, with a hardware or software switch between them?

There was a post[0] from a couple months ago for a piece of software called 'display-switch'[1]. It turns a simple/cheap USB switch into a n-computer KVM (however many systems the USB switch supports) by detecting the presence of the USB switch device on either system and switching the video input of the monitors using DDC/CI.

I've been using it for a couple of months and it's been a game changer. No more fiddling with monitor menus to switch inputs or wondering if the monitor is currently set to one computer or the other. You have to make sure your monitors support DDC/CI, though.

[0] https://news.ycombinator.com/item?id=29608967 [1] https://github.com/haimgel/display-switch

Re: Barrier: Share mouse and keyboard between computers

#90

Post by banana_giraffe »

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…

So, I might be missing something, but there are a couple of no-name HDMI/USB KVMs on Amazon in your price range (i.e., https://www.amazon.com/dp/B08NVKHRRT )

Some of the reviews suggest it acts as a pretty brain dead switch, which may cause problems with the OS. I know for a while I had a Windows 10 PC's monitor on a remote switch for silly reasons. I had to make sure to lock the PC before the monitor would turn off, otherwise some combination of driver/os/whatever would treat the disappearance of the monitor as a resolution change, and all my windows would get squished into 640x480. I could see KVMs like this triggering the same sort of madness.

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