3 ms·

I appreciate this question, I would also appreciate a solution, and the explanation of why it happens is interesting. However, what I really want is just to be

I appreciate this question, I would also appreciate a solution, and the explanation of why it happens is interesting. However, what I really want is just to be able to switch the input via command line. I know that there is a protocol that supposedly allows this (ddc?), But it seems that support for it is not standardized. This means the feature I want can't be found in the product specs. So my question: what's a monitor I can buy that will allow me to switch inputs by command line? (Ideally 4k)

balefrost 4y ago
If you just need "switch using keyboard", not necessarily "switch using shell", some KVM switches allow input switching using keypresses. For mine, it's <SROLLLOCK> <SCROLLOCK> <1-4> <ENTER>, though I think that can be customized.
- alanbernstein 4y ago
  Well, what I actually want to do is switch via my DIY macropad. My keyboard switch goes through that, without relying on any of the main computers. I had a cheap HDMI switch that worked the same way, but it just stopped working reliably after a month. I sometimes want independent control of the keyboard switch and the monitor switch, so I'm not sure if a KVM is the best option for me.
Davertron 4y ago
I think Dell has pretty good support for this, I had a pretty old Dell model before my current monitor and ddc worked fine with it. I now have an AORUS FO48U and it also supports it. I'm not sure it's always listed as a feature though when you're buying a monitor so it might be tricky. FYI, I originally learned about this stuff via https://haim.dev/posts/2020-07-28-dual-monitor-kvm/ https://haim.dev/posts/2020-07-28-dual-monitor-kvm/.
alin23 4y ago
In 5 years of getting support emails for Lunar (https://lunar.fyi/ https://lunar.fyi/), LG monitors were the least mentioned of all. They seem to have the best DDC compatibility of all monitors. I also keep a public monitor database here where you can check if a specific monitor usually works with DDC or not: https://db.lunar.fyi/ https://db.lunar.fyi/ The problem with LG is that they report very generic names so they can't be filtered well in the database. You can see what I mean with this query: SELECT DISTINCT ON ("DisplayProductID") name, ddc, "resolutionString", "refreshString", "dotsPerInch", "isHiDPI", "isRetina", "DisplayProductID" FROM displays WHERE ddc AND "is4K" AND width IS NOT NULL AND NOT "kCGDisplayIsVirtualDevice" AND NOT "isAirPlayDisplay" AND NOT "isTV" AND "DisplayProductID" != 0 AND name NOT LIKE 'Unknown Display%' -- Filter out those in a semi-connected state AND name LIKE 'LG%' AND "DisplayProductName" LIKE 'LG%' ORDER BY "DisplayProductID" DESC LIMIT 10; Also keep in mind that the GPU used and the hub/dock/adapter can affect this, so aim for as few indirections as possible. A direct connection is almost always the best.
- alanbernstein 4y ago
  Excellent, thank you!

balefrost 4y ago

If you just need "switch using keyboard", not necessarily "switch using shell", some KVM switches allow input switching using keypresses. For mine, it's <SROLLLOCK> <SCROLLOCK> <1-4> <ENTER>, though I think that can be customized.

alanbernstein 4y ago
Well, what I actually want to do is switch via my DIY macropad. My keyboard switch goes through that, without relying on any of the main computers. I had a cheap HDMI switch that worked the same way, but it just stopped working reliably after a month. I sometimes want independent control of the keyboard switch and the monitor switch, so I'm not sure if a KVM is the best option for me.

Davertron 4y ago

I think Dell has pretty good support for this, I had a pretty old Dell model before my current monitor and ddc worked fine with it. I now have an AORUS FO48U and it also supports it. I'm not sure it's always listed as a feature though when you're buying a monitor so it might be tricky. FYI, I originally learned about this stuff via https://haim.dev/posts/2020-07-28-dual-monitor-kvm/ https://haim.dev/posts/2020-07-28-dual-monitor-kvm/.

alin23 4y ago

In 5 years of getting support emails for Lunar (https://lunar.fyi/ https://lunar.fyi/), LG monitors were the least mentioned of all. They seem to have the best DDC compatibility of all monitors. I also keep a public monitor database here where you can check if a specific monitor usually works with DDC or not: https://db.lunar.fyi/ https://db.lunar.fyi/ The problem with LG is that they report very generic names so they can't be filtered well in the database. You can see what I mean with this query: SELECT DISTINCT ON ("DisplayProductID") name, ddc, "resolutionString", "refreshString", "dotsPerInch", "isHiDPI", "isRetina", "DisplayProductID" FROM displays WHERE ddc AND "is4K" AND width IS NOT NULL AND NOT "kCGDisplayIsVirtualDevice" AND NOT "isAirPlayDisplay" AND NOT "isTV" AND "DisplayProductID" != 0 AND name NOT LIKE 'Unknown Display%' -- Filter out those in a semi-connected state AND name LIKE 'LG%' AND "DisplayProductName" LIKE 'LG%' ORDER BY "DisplayProductID" DESC LIMIT 10; Also keep in mind that the GPU used and the hub/dock/adapter can affect this, so aim for as few indirections as possible. A direct connection is almost always the best.

alanbernstein 4y ago
Excellent, thank you!