This is the problem when I want to give a fast answer.... I make mistakes...
Neos is already Atari norm, so it can be directly connected to the joystick ports of the EnterMice... but it will not work as a mouse, only as a Joystick(if you press the left mouse button while switching-On the computer).
Observe the pin-outs:
[ Guests cannot view attachments ]
So you only have to add the Select(/Strobe) signal to pin 6 on the Neos to make it work on a program that supports it.
Pear added the connector on some of his EnterMices, when the owner asked it. But it is easy to make.
The main difference with the Atari norm is that the Neos use the main button lead to transport the select signal so, when you have it on mouse mode, any press on the left button will stop the mouse movement, because the signal is shorted to GND....
I don't know why they designed so badly the Neos mouse, probably due to the characteristics of the C64 joysticks ports, but it forced the use of the right mouse button as the click button.
----
Ok, once clarified this, I must say that the Boxsoft interface was declared obsolete long time ago, in favour of the EnterMice interface by genius Pear. Why?
-You can´t have at the same time a Neos mouse and a Joystick on port 1, their signals clash.
-EnterMice works on the undocumented K line, not used by any classic device or program. Joysticks ports 1 and 2 usually use the widely used J line.
-The EnterMice Joystick ports add two extra buttons, from lines K and L, and some actual games(mainly converted by great Geco) benefit from it.
-And last but main reason: Actually there are only a few known working
Boxsoft interfaces, two original ones owned from users of this Web page(Zozo is one of them) and an
ugly clone made by me from
Zozo's schematics...
Ok, but this doesn't mean that you can't use the Neos mouse, at least you can on these programs that use the unified mouse driver: EXOS(Basic and any other language), EGI and PaintBox.
Obviously.... a ball mouse will not give you the best feel, nor the best movement resolution, but it is up to you.
First you must install the mouse driver, downloading the latest version from
here.
The best information about the driver is on the EnterMice Wiki, the link Geco has already given to you, and I will not repeat it here.
But is important to point the list of devices that actually work with the Mouse Driver:
0 - Internal Joystick 2 buttons, Space and Enter
1 - Control 1 3 buttons
2 - Control 2 3 buttons
3 - Boxsoft 2 to 5 buttons
4 - EnterMice (default) 2 to 5 buttons
5 - Serial Mouse Systems 3 buttons
6 - Serial Microsoft 2 buttons
7 - SF3 USB Mouse 2 to 5 buttons
>7 - Not implemented