Editing Bus mouse (section)

== 9-pin D-sub, female plug ==
{|class="wikitable sortable" align="right"
! Atari !! Amstrad !! Commodore !! Assignment
|-
| 2
| 1
| 2
| XA
|-
| 1
| 2
| 4
| XB
|-
| 3
| 4
| 1
| YA
|-
| 4
| 3
| 3
| YB
|-
| 5
| n/a
| 5
| Middle button
|-
| 6
| 6
| 6
| Left button
|-
| 7
| 7
| 7
| +5V
|-
| 8
| 8
| 8
| Signal ground
|-
| 9
| 9
| 9
| Right button
|-
| n/a
| n/a
| Shell
| Chassis ground
|}

Female DE-9 plug, male socket.
Must not be confused with a 9-pin [[Serial interface|serial port]].
Serial mice' plugs tend to have thumbscrews, but on the Amiga, Atari and Amstrad, the cable's plugs did not, and some ports did not fit those plugs either.

Some third-party mice were made both for the Commodore Amiga and Atari ST, with a switch to select which system it was used with.
The Commodore Amiga and Atari ST mouse ports were also used for game controllers, and have thus inherited much of the
[[Atari interface#Atari joysticks|Atari joystick]] pinout.

Amstrad PCs however, have separate mouse and [[Atari interface#Amstrad|joystick ports]] that are ''not'' compatible with one-another.

===Atari ST===
The Atari ST has two DE-9 controller ports, the first for a mouse (or joystick) and the second only for a [[Atari interface#Atari joysticks|joystick]]). Both were interpreted by the keyboard's microcontroller.
The left mouse button is the same as the first joystick Fire button, and the right mouse button is wired to the second port's joystick-Fire button input.

===Atari PC===
Atari PC's have a Atari ST-compatible mouse port on the motherboard.<ref name="ataripcom">Atari PC Owner's manual 
[http://www.ataripc.net/files/documents/archives/ownersmanual/Atari%20PC%20Owners%20Manual%20-%20English.pdf Scan on ataripc.net]. Page 65. Dated 1987. 
Retrieved 2019-03-24</ref>.
The Atari PC supported also a third mouse button, but were shipped with the same two-button mouse as the Atari ST, only relabelled from "STM1" to "PCM1".
<ref name="ataripcnetpc3">AtariPC.net—[http://www.ataripc.net/pc3-8088/ PC3 8088]. Retrieved 2019-03-24</ref>.

===Amstrad PC===
The Amstrad bus mouse port was on the motherboards of 
Amstrad PC-1512<ref name="amstradpc1512">[http://www.seasip.info/AmstradXT/1512tech/section1.html Amstrad PC1512 Technical Reference Manual]. Copy on John Elliott's homepage, retrieved 2019-03-29</ref>
,PC-1640<ref name="amstradpc1640">[http://www.seasip.info/AmstradXT/1640tech/section1.html AMSTRAD PC1640 TECHNICAL MANUAL]. Copy on John Elliott'shomepage, retrieved 2019-03-29</ref>
and Sinclair PC-200<ref name="sinclairpc200">The Vintage Computer Club Malta—[https://web.computersmuseum.com/collection/sinclair/sinclair-pc-200/ SINCLAIR PC 200]. Retrieved 2019-03-26</ref>
(made by Amstrad).

A curious detail is that the two mouse buttons' lines were fed over the keyboard cable to the keyboard and reported by it as key codes.

===Commodore Amiga===
[[Commodore Amiga]] with AmigaOS were shipped with a two-button mouse.
Commodore made a three-button mouse only for the Amiga 3000UX that ran Amiga [[UNIX]] but many third-party Amiga mice also came with middle-button.
On the Amiga, quadrature signals are interpreted by circuitry in its custom chipset, with mouse support for both of its control ports.
A second Amiga mouse is used only in some two-player games, but the second port's circuitry could also be used for rotary controllers such as steering wheels.

In the late 1990s, there appeared third-party Amiga mice with [[scroll wheel]]s and up to five buttons. A special driver and utility are required to use them.
Pin 5, which is analogue-capable (originally for [[Atari interface#Paddles|paddle controllers]]) is used to send this input as varying current.
The third mouse-button is represented differently than earlier.<ref name="micromysv3">Micromys.de—[http://micromys.de/Amiga_devel.htm Micromys support page - Amiga mouse mode with wheel support]. Dated 2000. Retrieved 2019-03-24</ref>

===Commodore PC===
The Commodore PC-1, PC-10-III, PC-20-III, PC-30 and Colt have a single Amiga-compatible bus mouse port on the motherboard.<ref>Ancient Electronics blog—[https://ancientelectronics.wordpress.com/2015/06/17/commodore-colt-commodore-pc10-iii-pc20-iii/ Commodore Colt (Commodore PC10-III, PC20-III)]</ref><ref>The 8-bit Guy on Youtube—[https://www.youtube.com/watch?v=e63XWCW2ADY Commodore History Part 6 - The PC Compatibles]. Posted 2019-06-02</ref>

{{-}}