MICROSOFT COMPATIBLE MOUSE INFORMATION


Credits:

Microsoft Mouse is a trademark of Microsoft Corporation.
All information contained in this document is compiled
through my own experimentation.


Communications:

The Microsoft compatible mouse is connected to either a
bus or serial port. This documentation is for the serial
port. The communications parameters are as follows:

BAUD: 1200
BITS: 7
PARITY: NONE
STOP: 1

The signals used are:

COMPUTER MOUSE
SIGNAL DB-9 DB-9

RxDATA <- 2 1
TxDATA -> 3 3
DTR -> 4 4
RTS -> 7 2
GND 5 5




Data Format:

When the communications port is initialized and DTR is
active, the mouse responds with a hex 4D. This means the
mouse is ready.

After the mouse is online, when an event occures from the
mouse, the mouse responds with a three character event
status. The events are mouse movement, button press, or
button release. Below is the BASIC program I used to
determine the characters returned. The mouse was connected
to COM1. Following the BASIC program is a chart with bit
descriptions:

10 OPEN "com1: 1200, N, 8, 1, CS0, DS0, CD0" FOR INPUT AS 1
20 A = ASC( INPUT$( 1, 1) )
30 PRINT HEX$(A)" ";: GOTO 20


First Character:

Always 1

Left Button Depressed

Right Button Depressed

00 = Down Movement
11 = Up Movement
00 = Rht Movement
11 = Left Movement


6 5 4 3 2 1 0




Second Character:

Always 0

Horizontal Mickey Sign Bit

Horizontal Mickeys
Traveled


6 5 4 3 2 1 0





Third Character:

Always 0

Vertical Mickey Sign Bit

Vertical Mickeys
Traveled


6 5 4 3 2 1 0