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Submission + - Robert Dennard, Inventor of DRAM, Dies at 91

necro81 writes: Robert Dennard was working at IBM in the 1960s when he invented a way to store one bit using a single transistor and capacitor. The technology became dynamic random access memory (DRAM), which when implemented using the emerging technology of silicon integrated circuits, helped catapult computing by leaps and bounds. The first commercial DRAM chips in the late 1960s held just 1024 bits; today's DDR5 modules hold hundreds of billions.

Dr. Robert H. Dennard passed away last month at age 91. (alternate link)

In the 1970s he helped guide technology roadmaps for the ever-shrinking feature size of lithography, enabling the early years of Moore's Law. He wrote a seminal paper in 1974 relating feature size and power consumption that is now referred to as Dennard Scaling. His technological contributions earned him numerous awards, and accolades from the National Academy of Engineering, IEEE, and the National Inventor's Hall of Fame.

Comment Re:non-AI summary: (Score 2) 79

Adaptations beyond provided written instructions required in exactly this task, over the past 3 days: 1) recognizing that the hose clamp for the dishwasher drain was diabolically installed with the screw head toward the back of the cabinet, and at a rotation that jammed the screw head against the fixture; 2) understanding the specific drain coupling arrangement and determining how to loosen and get clearance for each piece before uncoupling the old unit; 3) inspecting the couplings for reuse; 4) horrid cabinet design makes single-handed close quarters lift difficult, order a small lab jack and put it on a stack of old encyclopedia volumes to get the new unit up to the height to engage the locking ring; 5) previous experience in checking that the drain couplings are properly positioned and secure. Circumscription! Cyc! Parrots! Help me AI-wan Kenobi!

Comment Nostalgie de la boue (Score 3, Interesting) 33

As a builder of model planes and rockets in my youth, it was nostalgic and humorous to see his out-the-car-window method for testing stability (center of pressure vs center of mass). At an age with no direct access to cars, we did this by tying a string around the rocket tube at the balance point, then swinging it around to see if it tumbled. My first programming exercise was to mechanize the Barrowman equations for center of pressure estimation, on a Wang programmable calculator.

Comment Re:sequel (Score 3, Interesting) 74

SQL was the sequel to SEQUEL, which in turn was described by the linked 1974 paper. As a snapshot from history, in a course taught maybe 1973 by Prof. Melkanoff at UCLA, I recall a statement (paraphrased) "we have been hearing about a recent development by Ted Codd at IBM Research called the Relational Model, which looks promising as a path forward in databases.". We then were introduced to Select, Project, Join.

Comment Re:My first programming language (Score 2) 107

My first real computer exposure, through the IBM school discount obsolete equipment time warp, was 1620 Model 1. Core memory for this model was I believe in an oil bath with a heater, and required upwards of 20 minutes to get to operating temperature after cold power-on.

Arithmetic in Model 1 was by table lookup from tables loaded into specified memory locations. I believe Model 2 used an actual ALU rather than table lookup.

1620 required 1 memory location per decimal digit; 2 memory locations per alphanumeric character. The disk monitor that we usually used, required typing branch instruction 4900796 into the console typewriter. 1620 punched card in/out was to programmer chosen memory locations.

The contemporaneous IBM 1401 represented alphanumeric card data in one memory location per card column, 6 bits plus Check (parity) and Flag (delimiter bit for variable length fields). Card and print in/out was to fixed memory regions, card input to locations 1-80, constituting a "card image" in the specific BCD encoding. Some of these machines served as card/tape and tape/print machines alongside expensive wide word "scientific" machines like 7094 (which I never used) that usually worked tape-to-tape.

Comment Re:My first programming language (Score 2) 107

No faking here: I coded an audio delay/mix experiment in 8080 machine code, keyed it in with front panel switches on an Altair 8800, and obtained interesting and at times disorienting audio effects through an A/D and D/A board. The first program that I wrote was for a Wang programmable calculator, using IBM Porta-Punch cards (like "hanging chad" ballot cards). I have diagnosed and repaired discrete transistor line drivers for core memory: the electrons must go uphill both ways.

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