I believe 3 wire memory was first introduced by IBM in their 360 systems, and it was a very large development effort. They would almost certainly have patented their way to do it, but I have not checked.
Marc From: cctalk <[email protected]> on behalf of "[email protected]" <[email protected]> Reply-To: Jon Elson <[email protected]>, "[email protected]" <[email protected]> Date: Thursday, April 18, 2019 at 7:08 PM To: Noel Chiappa <[email protected]>, <[email protected]>, "[email protected]" <[email protected]> Subject: Re: Plane of core memory On 04/18/2019 03:15 PM, Noel Chiappa via cctalk wrote: > From: Jon Elson > As soon as somebody figured out that you could combine the sense and > inhibit wires, everybody immediately went to 3-wire planes. I"m suprised the idea wasn't patented. Or maybe it was, and they made the license widely available at modest terms? I was thinking the same thing, but can't find any references to who invented it. it certainly sounds like the sort of thing to get a patent on. Point of interest, my freshman advisor was Bill Papian, who was Jay W. Forrester's grad student when he invented coincident-current core memory. Jon
