About USB to PS/2 : Not every USB mouse will work with PS/2 passive adapter (it needs to be "dumb enough").
As such, not all combo ports on boards support simultaneous mouse + keyboard inputs (as you now know).

DoomGuy II wrote on 2023-05-06, 15:54:

So, I tried the PS/2 Y cable that I recently got in the mail and plugged it in. Unfortunately, I could not get both the mouse and keyboard working simultaneously. Only one or the other on the keyboard output on the Y-cable. Nothing happens on the mouse output.

However, I pulled out my HP Omnibook 4150 to test and see if the Y-cable was actually working properly. And sure enough, after plugging it into the PS/2 port on the laptop, with an appropriate mouse and keyboard into their respective ports, it actually worked very beautifully. I can move the mouse and operate the keyboard as normally.

In Asrock Z77 Extreme a PS/2 is not a combo port. It's connected only to keyboard DATA (59) and CLOCK(58) signals of a SIO controller. Mouse signals (pins 57,56) are not connected to PS/2 (the pins can be used also for something else).
IMO, the Y-cable is usually for laptops.

Roman555 wrote on 2023-05-06, 19:06:

In Asrock Z77 Extreme a PS/2 is not a combo port. It's connected only to keyboard DATA (59) and CLOCK(58) signals of a SIO controller. Mouse signals (pins 57,56) are not connected to PS/2 (the pins can be used also for something else).

You're probably talking about the Z77 Extreme3.

https://www.asrock.com/mb/Intel/Z77%20Extreme3/index.asp

But I have the Extreme6, which DOES have a PS/2 combo port.

https://www.asrock.com/mb/Intel/Z77%20Extreme6/

Currently using it on mine with a PS/2 mouse and it works just fine. The trouble is getting the keyboard and mouse working simultaneously with a Y-cable on the same port. And I have seen certain boards with it that can utilize a Y-splitter to make it work that way.

DoomGuy II wrote on 2023-05-06, 20:05:

You're probably talking about the Z77 Extreme3. […]
Show full quote

Roman555 wrote on 2023-05-06, 19:06:

In Asrock Z77 Extreme a PS/2 is not a combo port. It's connected only to keyboard DATA (59) and CLOCK(58) signals of a SIO controller. Mouse signals (pins 57,56) are not connected to PS/2 (the pins can be used also for something else).

You're probably talking about the Z77 Extreme3.

https://www.asrock.com/mb/Intel/Z77%20Extreme3/index.asp

But I have the Extreme6, which DOES have a PS/2 combo port.

https://www.asrock.com/mb/Intel/Z77%20Extreme6/

Currently using it on mine with a PS/2 mouse and it works just fine. The trouble is getting the keyboard and mouse working simultaneously with a Y-cable on that port. And I have seen certain boards with a combo port that can utilize a Y-splitter to make it work that way.

Combo means it supports mouse and keyboard on the same port, but NOT NECESSARILY SIMULTANEOUS https://en.wikipedia.org/wiki/PS/2_port, if you will plug a mouse in to the ps2 port of this motherboard https://www.asrock.com/mb/Intel/Z77%20Extreme3/index.asp it will not work at all. For simultaneous operation you need certain signals present on the ps2 port.

If you have some soldering skills, you can try running 2 wires from Super I/O chip with the data and clock signals for the ps2 mouse to the 2 not connected pins of the ps2 female plug of the board.

Years ago when I bought a PS/2 Y cable for my Compaq laptop, the company that sold the cable had three different kinds of PS/2 Y cables; One for Compaq and two other kinds for other Laptop brands. I suppose they where all wired differently somehow(?)

DrSwizz wrote on 2023-05-06, 21:06:

Years ago when I bought a PS/2 Y cable for my Compaq laptop, the company that sold the cable had three different kinds of PS/2 Y cables; One for Compaq and two other kinds for other Laptop brands. I suppose they where all wired differently somehow(?)

Generally for "PS/2 age systems", like these laptops and their docks, the only difference in the splitter is which connector is purple - the computer only supports one kind of device without the splitter (the mouse for IBMs) and the other must go on the "alternate" pins...

The "autodetecting" port already existed by then but wasn't very common, at least openly - and I'd have expected it nowadays to also support splitters but this very discussion suggests otherwise. Guess it's par for the course from manufacturers using SuperIO chips with a full floppy disk controller inside, then giving you the choice between NONE and ONLY A: 1.44M ?

If everything else fails, you could buy a PS/2 expansion card, if you have a spare PCI slot in there. They shouldn't be too expensive.

Roman555 wrote on 2023-05-06, 19:06:

In Asrock Z77 Extreme a PS/2 is not a combo port. It's connected only to keyboard DATA (59) and CLOCK(58) signals of a SIO controller. Mouse signals (pins 57,56) are not connected to PS/2 (the pins can be used also for something else).

exactly

DoomGuy II wrote on 2023-05-06, 20:05:

You're probably talking about the Z77 Extreme3.

no, you can see for yourself https://www.electronica-pt.com/esquema/ ... ew)-73991/ opens in https://github.com/OpenBoardView/OpenBoardVie … ases/tag/9.95.0

You probably need to buy the correct PS/2 splitter that routes separate keyboard and mouse traffic back to a single port.

Reference this message from the weecee PC thread.

Re: Tiny Vortex86-based DOS gaming PC - weeCee

DoomGuy II wrote on 2023-05-06, 20:05:

You're probably talking about the Z77 Extreme3. […]
Show full quote

Roman555 wrote on 2023-05-06, 19:06:

In Asrock Z77 Extreme a PS/2 is not a combo port. It's connected only to keyboard DATA (59) and CLOCK(58) signals of a SIO controller. Mouse signals (pins 57,56) are not connected to PS/2 (the pins can be used also for something else).

You're probably talking about the Z77 Extreme3.

https://www.asrock.com/mb/Intel/Z77%20Extreme3/index.asp

But I have the Extreme6, which DOES have a PS/2 combo port.

https://www.asrock.com/mb/Intel/Z77%20Extreme6/

Currently using it on mine with a PS/2 mouse and it works just fine. The trouble is getting the keyboard and mouse working simultaneously with a Y-cable on the same port. And I have seen certain boards with it that can utilize a Y-splitter to make it work that way.

Sorry, I misused the meaning of "combo". I meant you can't use ps/2 keyboard and ps/2 mouse simultaneously in the ps/2 port. Also soldering additional wires from SIO to PS/2 won't help because a mouse signal is used in a GPIO mode
UPD. It's in Z77 Extreme4. In Z77 Extreme6 (thanks rasz_pl for the link to the boardview) the mouse signals of SIO are unconnected. So maybe adding wires will work.

agent_x007 wrote on 2023-05-06, 16:29:

About USB to PS/2 : Not every USB mouse will work with PS/2 passive adapter (it needs to be "dumb enough").
As such, not all combo ports on boards support simultaneous mouse + keyboard inputs (as you now know).

Actually it has to be "smart" enough to detect the connection type, and choose protocol accordingly 😀 But yes, modern mice generally only support the USB protocol.

Assuming that the mouse OP got working with the laptop is the same that didn't work with the ASRock board, I'd also guess the problem is related to the PS/2 controller rather than the mouse, that it can't handle more than one device like you're suggesting. Maybe the mobo manual can shed some light on that?

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An active USB to PS/2 adapter would solve the problem otherwise. I've had luck with Chesen CSC0101A based ones, like this one from Startech. The specific Hama ones I'm using seems to be out of production, but anything with the same chipset should work the same, and Startech seldom disappoints. They can handle mouse wheels, more than two buttons, etc. Be aware that old KVM switches might not though.