Michael J. Mahon wrote: > Matthew Carpenter asked: > > > I would like to know if there is any reason to have a joystick with > >three buttons on an Apple IIGS. > > > > My reason in asking is that while I was at the Goodwill a couple days > >ago I saw a joystick just like the one a friend I used to know about 12 > >years ago had on his IIGS. The only difference being that this one I have > >found is a PC version of the joystick. I bought the joystick when I left. > > > > This is a Gravis joystick, it has one fire button on the stick and two > >buttons on the base. I found a black and white picture at the following > >url: > >http://www.atarimagazines.com/v7n6/gravis.jpg > > > > I went into the CSA2 FAQ and found info on making an adapter to hook up > >PC joysticks to an Apple II and noticed that the adapter would only have > >two of the buttons connected to anything. I'm wondering what it would be > >needed for the third button. > > The 9-pin external IIgs joystick connector has only two pushbutton > lines, but if you plug into the internal 16-pin DIP Game Port, all three > pushbutton lines are available (as well as two more paddle inputs). Sorry, that is not correct. The external D9 connector on the IIe and IIgs provides access to both joysticks (four paddle inputs) and three switches/buttons (seven pins in total) plus power and ground. The IIc's game connector only provides access to one joystick (two paddle inputs) and two buttons. It also supports a mouse. The internal 16-pin game connector on the II+ and IIe provides access to the four paddle inputs, three switches, annunciator outputs (4 in total) and strobe output, plus power and ground. There are two unused pins. The differences between the IIgs and IIe 16-pin game connectors are: - The IIgs doesn't have a strobe output (the pin supplies a static +5V signal through a resistor). - The IIgs has a fourth switch input, only available on this connector. - The IIgs connector is oriented the opposite way around from the II+ and IIe. There is one unused pin on the IIgs 16-pin game connector. -- David Empson dempson@actrix.gen.nz