In article , "BUFF" wrote:

It is possible to use the throttle with another joystick if the game lets
you assign axis etc. & supports multiple controllers.
However, the Saitek throttle has to be connected to the Saitek joystick as
all the "brains" are in the joystick (just put the Saitek joystick out of
the way).
However, if you are having problems related to PS/2 then obviously this
won't change that.

Ok, but my intention was indeed to bypass the "brains" and thus the PS/2
connections, since I think the latter is only needed to simulate pressing keys
on the keyboard for the rotary knobs and all the throttle and joystick
buttons.
I have to find if what make the throttle and rudder level works are two
potentiometers and connect their pins or wires directly to the Y-cable.
But all the above is useless if the MS Sidwinder joystick takes all control on
the gameport.That can be the case, since I guess it needs some sort of
controller to make the hat switch work. And all the pinout charts I've found
on the net about the gameport don't specify any hat switch pin...