----- Original Message ----- From: "Sridhar Ayengar" <ploopster at gmail.com> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Sent: Friday, February 26, 2010 2:54 PM Subject: Re: joysticks for dos games Speaking of which I snagged a CH Products F16 flight stick and the matching throttle today at a thrift store. Do you need a special dual joystick card to use them both at the same time? The throttle looks like you might need to loop it into the keyboard port as well.

The IBM PC games controller interface card allowed for 4 variable resistor inputs (conventionally a pair of 2 axis joysticks and 4 buttons. THe variable resistors controlled the times of the 4 sections of a 558 (think of a quad 555 timer chip, but the secions are internally wired as monostables). Writing to the port address triggered all the monostables, rhey could be read back, along with the 4 button inputs at the same address. There was a single DA15 connector carring the 8 input signals, +5V and ground. Many clone cards had a pair of DA15 connectors. One had the IBM pinout, the other carried the same signals, but with the pin for variable resistor 0 swapped with that for VR2, VR1 swapped with VR3, and similarly for the buttons. Te idea was that you could plug in a pair of joysticks, each wired to the VR0 and VR1 pins and have them appear as a dual joystick plugged into the IBM card. Alternatively, there were Y cables available which did the same thing if you just had a single DA15 socket on the card. Were there joystick interfaces that allowed for more inputs? I've not seen one, but I am not well-up in games. -tony