View Full Version : AT&T 6300 / Olivetti M24 mice alternative: Logitech P7-3F

October 20th, 2017, 07:34 PM
It is becoming very hard to find an actual 6300-branded or M24-branded mouse. Luckily, the 6300/M24 mouse is actually a Logitech OEM mouse, specifically model P7-3F, which shows up on ebay from time to time, and works just fine. However, that exact model was shipped with three connectors: 9-pin male, 9-pin female, and 10-pin "bus mouse" connector. You can see examples of all three here:

9-pin male: https://www.ebay.com/itm/Vintage-Logitech-model-P7-3f-Three-Button-Serial-Mouse-/122734865051
9-pin female: https://www.ebay.com/itm/Logitech-serial-mouse-vintage-P7-3F-9F-non-working-/192338776379
bus connector: https://www.ebay.com/itm/Logitech-bus-mouse-with-8-bit-isa-card-vintage-P7-3F-/192338646525

For the record, the correct connector you want to use with a 6300/M24 is the 9-pin male connector. The mouse port on the keyboard is 9-pin female.

While the 6300/M24 house has two buttons, the Logitech equivalent has three buttons. I don't recall if the middle button is functional when connected, but it isn't cause for concern.

Hope this helps someone in the future...

October 20th, 2017, 09:48 PM
Jim, isn't the 6300/M24 mouse a "dumb" mouse? That is, no real active logic, just a quadrature affair?

October 21st, 2017, 11:40 AM
Hello, yes the M24 mouse is just quadature mouse. So you also can adapt Commodore Amiga, Atari ST mices.

You can even find ST/Amiga mouse to USB (but PS/2 protocol) mouse adapters...

October 22nd, 2017, 02:36 AM
Tektronix also used this mouse in the past it has the 9 pin male connector only the pin-out was different.
To fix the pinout issue you can just swap the contacts inside the mouse.

Also the third button is connected to the keyboard controller but i have not found a use for it.

If you want to make a really fancy mouse you can get one of the early optical mouse and wire the quadature signals from the sensor and buttons straight to the keyboard just remove the PS/2 or USB controller chip ;)

November 5th, 2018, 03:57 PM
Just wanted to add that the version with the 10-pin "bus mouse" connector works as well with an AT&T 6300 / M24. You just need to open the mouse up, unplug the mouse cord (connected with a 2x5 IDC connector) and wire it to a male DB9 plug. The pinout on the mouse side is not hard to figure out (it's a simple single-sided PCB - just follow the traces to the three buttons or to the two rotary encoders). The pinout on the M24 keyboard side is as per the Theory of Operation manual.

I've tested it with the SYSTEM.EXE program and it works.