The Mouse 1351 is a mouse made by Commodore

Commodore International

Commodore is the commonly used name for Commodore Business Machines , the U.S.-based home computer manufacturer and electronics manufacturer headquartered in West Chester, Pennsylvania, which also housed Commodore's corporate parent company, Commodore International Limited...

 in 1986, which can directly be plugged into the 9-pin control port of a C64

Commodore 64

The Commodore 64 is an 8-bit home computer introduced by Commodore International in January 1982.Volume production started in the spring of 1982, with machines being released on to the market in August at a price of US$595...

/128

Commodore 128

The Commodore 128 home/personal computer was the last 8-bit machine commercially released by Commodore Business Machines...

/D/DCR.

Description

The Commodore Mouse 1351 has two buttons on the upper side and a ball on the bottom side. It works in two operating modes: the joystick mode and the proportional mode. The operating mode is decided when the computer is switched on: when the right mouse button is pressed, the mouse goes into the joystick mode, otherwise (default) into the proportional mode.

The "Mouse 1351" contained next to the manual also a Test/Demo-Diskette.

Joystick mode

The joystick mode enables the use of the mouse with every joystick

Joystick

A joystick is an input device consisting of a stick that pivots on a base and reports its angle or direction to the device it is controlling. Joysticks, also known as 'control columns', are the principal control in the cockpit of many civilian and military aircraft, either as a center stick or...

-compatible software. It is also provided as a "reserve" for the case when the used software does not support the proportional mode.

Proportional mode

The proportional mode needs a special driver program in machine language to unfold its full abilities. Here the mouse works as followed:

1. Every movement is registered inside the mouse. The current position is transfered modulo 64 every 512 micro seconds to the SID registers POTX (for the x-position) and POTY (for the y-position), without the need of software.

Register assignment:

Bit position	7	6	5	4	3	2	1	0
POT register	X	P5	P4	P3	P2	P1	P0	N

wiht:
X ....... bit not used
P5-P0 ... mouse position modulo 64
N ....... special (noise) bit

2. The left mouse button is connected as a joystick fire button.

3. The right mouse button is connected to the contact of the upward movement of the joystick.

source: 1351 Mouse User's Manual

Manual

The "Commodore 1351 MOUSE User's manual" contains information about the mouse and the software interface in eight languages, as well as English listings for mouse driver and a pin-out.

Contents:
Deutsch .............................. Seite 1-13
Francais ............................. Page 15-23
English .............................. Page 25-33
Italiano ........................... Pagina 35-43
Español ............................ Página 45-54
Nederlands ......................... Pagina 55-64
Dansk ................................ Side 65-73
Svenska ............................. Sidan 75-80

Basic and machine language
programs for 1351 mouse and C 64 ..... Page 81-86

Basic and machine language
programs for 1351 mouse and C 128 .... Page 87-92

1351 Mouse Pin-Out ................... Page 93

Contents of the test/demo disk or utility disk

The content of the first side was an English menu program for the C64/128, which contained a standard and a more advanced driver as well as a short demo program for testing the mouse.

Side 1:
5 Startup.102486 PRG
3 COMM 1351 USR
1 MOUSE64.BAS PRG
2 MOUSE64.BIN PRG
7 MOUSE64.SRC SEQ
2 M1351.64.BAS PRG
2 M1351.64.BIN PRG
11 M1351.64.SRC SEQ
5 DATA64 PRG
6 DEMO64 PRG
2 MOUSE128.BAS PRG
1 MOUSE128.BIN PRG
7 MOUSE128.SRC SEQ
4 M1351.128.BAS PRG
2 M1351.128.BIN PRG
12 M1351.128.SRC SEQ
5 DATA128 PRG
6 DEMO128 PRG
1 MOUSE.POINTER PRG
3 SPRITES.0E00 PRG
575 BLOCKS FREE

Side 2:
GEOS Upgrade
18 upgrader USR<
7 gRABBER UPGRADE USR
7 mERGE UPGRADE USR
10 GEOdEX UPGRADE USR
0 BLOCKS FREE

On side 2 is the GEOS

GEOS (8-bit operating system)

GEOS is an operating system from Berkeley Softworks . Originally designed for the Commodore 64 and released in 1986, it provided a graphical user interface for this popular 8-bit computer.GEOS closely resembled early versions of Mac OS and included a graphical word processor and paint program...

 upgrade to version 1.3 (1986) by Berkley Softworks for the Commodore 64C