PS/2 to Dreamcast adapter

[Sparkfist]

For starters no I'm not looking for the adapters, I've been searching recently and wondering if its possible to connect something like a mouse or keyboard directly to the controller ports.
I looked at a pinout of a PS/2 keyboard, it only uses 4 connections, a mouse uses 6. So I'm a little confused.

I'm sure that you can directly connect the mouse/keyboards as they sell adapters as small as the ones that take a USB-PS/2 so there is nothing but crossing pins.

[gannon]

If you look at it, only 4 of the pins on a ps/2 mouse of keyboard are actually used. Search for ps/2 pinout on google.

[Sparkfist]

Well would the clock wire be required? The pinout I found of the mouse had 5 or 6 wires and one wire was the clock, and another was reserved. I dont know what the hell resevered means.

If it only takes 4 or 5 wires then that would be perfect. The only thing I need to figure is how to make a switch so I can turn the mouse off when a controller is pluged in.

[gannon]

The only needed connections should be clock, data, power, and ground. I'm not even sure if it'll work, but I'm sure it's worth a try.

[Sparkfist]

Well now that I've solved the problem with my Dreamcast I'll see about disection the PS/2 trackball mouse I have lying around. The keyboard I really didnt care about I have the Dreamcast one.

P.S. It seems Sega built a safty into the system you have to have the fan plugged in other wise the system just shuts down, guess they're really worried about over heating.

[gannon]

did they build the safety with a 3 wire connector instead of the standard 2 for the fan?

[Sparkfist]

No just two, I was looking at it today and finally noticed that the connection to the fan wasnt there, and the plug was stuck under the mobo. So after disassembling the whole thing I tured it on got passed the time/date setup and turned it off at the game screen.

Also, Gannon if you know of a place that sells fans like the Dreamcast please tell, and when I say that I mean ones that use 5v rather then 12v.

[gannon]

you do know that 12V fans will run on 5V, they'll just run slower, right?

Also, I'd try mouser or radio shack for the fan.

[Sparkfist]

Nope didnt know you can do that with the fans, and thanks for the info. I can use it with other portables when I get the chance.

[kylerock96]

epic bump


so,did this work?

[limpport]

Reading though this, I'm curious now too. I did a Google search for "connect a mouse to dreamcast" to see if there was anything, and the first result was this topic

[tom61]

Reading though this, I'm curious now too. I did a Google search for "connect a mouse to dreamcast" to see if there was anything, and the first result was this topic

If that's the case, let me answer this multiple year old thread.

You can't just splice some wires together to get a PS/2, USB or other type of non-Dreamcast mouse or keyboard to work on the Dreamcast.

More technical: PS/2 protocol uses a simple slow speed serial interface to communicate with a PC, whereas the Dreamcast's controllers use a much more sophisticated, higher speed bi-directional serial bus with identification descriptors for different devices called 'Maplebus'. I don't have links ready for more specs, as most information is now findable only on the Internet Archives now. Commercial controller adapters most likely use a microcontroller to convert the signals back and forth to the Dreamcast (all the adapters I've taken apart have bare chip covered in black epoxy.)