NO! NEVER PLUG A MSX DEVICE TO THE ENTERMICE JOYSTICK PORTS!
THEY HAVE A DIFFERENT PIN-OUT(Atari standard) SO YOU CAN BREAK SOMETHING!
It only accepts PS/2 mouses...
Think that the target Enterprise user doesn't have a MSX mouse nor a Neos mouse. Internally it is a PS/2 to MSX adapter attached directly to the Enterprise connectors. It also has extended MSX protocol, it is wheel compatible...
The original Boxsoft Interface shared the Control 1 intersections in the keyboard grid, but in the Entermice design other undocumented intersections had been used to avoid some incompatibilities.
As a result, the next SymbOS version has to be modified to read the Entermice approach. Not a complicate task so, probably Prodatron will leave the original Boxsoft mode as an option.
In that case, if the Boxsoft mode survives the next SymbOS version, a really easy adapter can be done to connect a MSX mouse to the Entermice. YOU CAN'T PLUG DIRECTLY A MSX MOUSE TO THE PROVIDED JOYSTICK PORTS as theAtari standard has the +5 volts and ground on different pins than the MSX standard. Also the Entermice joystick ports lack the output pin STROBE that MSX mice need.