Main page

What is PS/2 and what mice may be?

PS/2 connector PS/2 is a name of old PeeCee series from IBM. PS/2 computers are forgotten long time ago, but they have interesting solution - synchron serial port for mouse. It was times very early before USB, and this solution become popular in third-party PeeCee motherboards because of it allows to be free all RS-232C ports. Now ATX standard defines PS/2 mouse connector as default, and PS/2 mice become very popular. Before this time most popular mice are RS-232C (they have similar DB-9 connector that Amiga mice, but imcompatible electrically). PS/2 mice have MiniDIN connector with six pins (see photo). RS-232C mice have extremely poor quality - mouse pointer with them doesn't move, it jumps. It is because generic 3-button RS-232C mouse reports about movement only 25 times per second. PS/2 mice work better - all of them can report about state 80 times per second, and most of them (excluding 5-button or wheel mice) can report 200 times per second.

RS-232C mice were accessible for Amiga users - there was some software drivers and hardware controllers. But it is not good solution because of described above. PS/2 mice were not accessible on Amiga at very long time - but this time now is in the past.

PS/2 mouse can work on Amiga with my controller too well as works native Amiga mouse. But you can ask - why you will do my controller, if your Amiga mouse works similarily?

Here is an advantages of PS/2 mouse usage instead of native Amiga mouse:

Optical Sensor Some words about optical mice - if you don't know what is it. Agilent company developed in later 1999 new optical sensor, that can be used in mice instead of ball - see center of the left picture. Optical mice don't have inertia, don't require clearing and mouse pads, always move smoothly, and are much more comfortable than mechanical ones. Of course, them are relatively expensive - like 25-30 USD for Genius NetScroll Optical - but mouse cost is not very important in comparison with all computer cost, and I don't recommend you economize on mouse in damage for your comfort.

Additional Buttons Additional buttons (look at two red buttons at the left side of the mouse) can be used for similation of some actions, like keys pressing - for example, «Back» in Web-browser. Wheel(s) are used for scrolling, selection of cycle-gadget item (supported in MUI now) and any other purposes.

Adwantages of my PS/2 controller in comparison with RS-232C mice you can read here. Additionally, RS-232C mice require +12v and -12v logical levels and additional scheme for level transformation - and PS/2 mice has simple TTL logic levels with +5v power.

Where to get it?

It is a self-made product. I am not a factory building this controller. If you want it - do it by yourself or ask your friend. This manual contains all required instructions, schemes and files. It will cost for you only material and your work cost.