Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!rutgers!caip.rutgers.edu!froncio From: froncio@caip.rutgers.edu (Andy Froncioni) Newsgroups: comp.sys.ibm.pc.hardware Subject: Game Port A-to-D Keywords: A-to-D game port Message-ID: Date: 26 Jun 91 16:46:15 GMT Organization: Rutgers Univ., New Brunswick, N.J. Lines: 26 I'd like to do A-to-D from a PC/AT game port, for financial reasons. I only need very slow speeds, so I think I'm on safe ground. From my understanding of the game port, it is basically a 555-timer running in astable mode and whose pulse frequency is set by the charge-up of a capacitor in an RC circuit. The R in this circuit is the joystick potentiometer and the whole thing is hooked up to +5v. I figure it should be possible to substitute the analog signal instead of the +5v and use a fixed resistor instead of a pot. to "trick" the 555-timer into modulating its pulse frequency linearly with the analog signal. Has anyone done this before? Can soem one help me with making sure that the zero-offsets and the full 0-5v input range is covered? Thanks, Andy -- Andy Froncioni CAIP Center Parallel Computing Lab froncio@caip.rutgers.edu Rutgers University, Piscataway, NJ