search

thatoddmailbox / kvm

An open-source HDMI Keyboard/Video/Mouse (KVM) switch, which lets you switch two monitors and four USB devices between up to three computers.
10 stars 1 forks source link

Collection of resources and idea #1

Open NiKiZe opened 2 years ago

NiKiZe commented 2 years ago

I'm interested in something similar. My idea is to have "a stack" that can be used with separate boards for video & USB.

To replace your setup it that stack would be

Maybe this is this something that is interesting to track here?

(will try to get back with some resources I have found so far)

thatoddmailbox commented 2 years ago

Thanks for reaching out, that sounds like a really interesting idea! You could definitely move the HDMI and USB switches onto separate modular boards; however, I would wonder how you would switch between the displays? For this project I had the keypad on a separate board with a 3x3 grid of buttons, but if you have a flexible number of displays then I'm not sure how you would do that?

Also, this KVM can switch three HDMI ports onto one display, but what if you needed more (or fewer) ports? Could you mix a 3-to-1 with a 4-to-1 board? I think you would also need to make sure the boards are fairly compact, since otherwise the end result would be very bulky.

Overall I think it's a really cool idea, and I would definitely be interested -- if you know of any existing resources, it would be great to hear about them!

NiKiZe commented 2 years ago

Great to hear that. The "CPU" would be separate (or combined) and could have input from external switch board.

Just to agree on terminology Your board has 3 "channels" HDMI A, HDMI B, USB

The simple way would be to expose 3-4 bits of sel lines, that could allow for up to 16 input selections. Another would be to use i2c or similar between the boards (all on the same bus) But I'm thinking that both could be possible. You used one "set of buttons" to control each channel individually, my idea is probably to have all channels switch input from the same selection. - but I hope that both could be possible.

So for my main use-case 3-4 bits of selection, would be enough, that could be controlled directly from pikvm, or by a i2c bus, or a serial interface, I still see that as being controlled by a CPU that could be different between the 2 versions while other parts being the same.

Starting to collect data on some maybe interesting chips:

I hope that most of these can be used in a Hi-Z state, which would enable 2 chips to be connected in parallel and that way double the number of inputs, and just select between them by enable.

What I hope exists somewhere is a HDMI + 1 channel MUX that could be used to switch both HDMI + USB in the same package.

I still have ways to go here, I hope to get some more time to clarify my ideas more.