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Man I didn't even realize that Quora was still around, let alone prominent people still answering questions on it. I deprioritized it in my Kagi searches months ago and even then I didn't notice that much of a change in the quality of my searches.
I'm pretty sure Kay's not quite correct about the Eniac not being a stored program computer. In it's original form it obviously was not, as it had to physically reconfigured to solve different problems. However, after the war it was rebuilt to operate like any other stored program (von Neumann architecture) computer, as it was the first recipient of the design philosophy seen in the EDVAC report. It operated in that mode from '48 to '55, when it was decommissioned.
ENIAC in Action: Making and Remaking the Modern Computer is an excellent summary of the initial design and redesign of the Eniac.
Apparently Eckert (John Mauchly and J. Presper Eckert designed the ENIAC) claimed that von Neumann basically stole their idea of the stored program and that they had already came up with the idea and he just took it and ran with it as if it was his
And John Von Neumann? He came and looked at our stuff and went back to Princeton and wrote a long document about the principles. He gets a lot of credit but the inventions were ours. Someday I’ll write a book on who really invented the computer.
Johnny learned instantly, of course, as was his nature. But he chose to refer to the modules we had described as “organs” and to substitute hypothetical “neurons” for hypothetical vacuum tubes or other devices which could perform logical functions. It was clear that Johnny was rephrasing our logic, but it was still the SAME logic. Also, he was introducing different but equivalent symbols; nevertheless the devices still did the same things. Johnny did NOT alter the fundamental concepts which we had already formulated for the EDVAC.
Small wonder, then, that computer history gave von Neumann the credit. Eckert and I, who left the Univ. of Penna. In 1946, no longer had access to the documents which might have helped to show “who did what, when.” But after many years, litigation has unearthed some of those documents, and historians can read what was once classified. But, even after declassification, those reports are not accessible to most people, since they were reproduced in such small quantities. Nevertheless, we hope that more historians will refer to them.
EDSAC as early as 1949 had an "initial orders" module. A boot-up ROM. There was a bank of rotary selector switches, to set the octal digits in each ROM word.
David Wheeler (of subroutine fame) figured out the most sensible thing to put in the tiny ROM was a paper tape loader and mini-assembler that loaded the rest of itself from paper tape. So at switch-on the machine would start reading the tape input and run. Programs could be written on the teletype with mnemonics and relative addresses in octal.
It seems a little strange that more advanced later machines like the original PDP-11 from 1970, couldn't "autostart" from ROM like that. You had to toggle in a bootloader.
I think that was because core memory was non-volatile. (EDSAC didn't use core; it had a refreshing DRAM-like delay line memory.) With core, you only had to toggle the bootloader into once and, provided your software didn't accidentally overwrite it, it was still there after a power cycle. So re-toggling in the boot loader was not really that common, despite how much lore surrounds it.
DEC supplied optional boot rom cards for UNIBUS, starting with the BM792, which arrived as a 32 x 16 matrix of diodes. You had to remove some of the diodes by hand to set the boot code.
Later cards used PROMs, and were pretty fancy. The M9312 had 512 words and included some basic CPU diagnostics. Different variants handled boot from disk, paper tape, console, etc, and you had to specify the options you wanted when you bought the card.
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If you have too much adblock, as I do, you can never visit quora.com. The security check will just loop infinitely.
Funny. Just tested that because I'm always told: too complicated, nothing will work!
And got no check at all.
Maybe the times are changing. Went through with Adblock and vpn. No looping.
Man I didn't even realize that Quora was still around, let alone prominent people still answering questions on it. I deprioritized it in my Kagi searches months ago and even then I didn't notice that much of a change in the quality of my searches.
I'm pretty sure Kay's not quite correct about the Eniac not being a stored program computer. In it's original form it obviously was not, as it had to physically reconfigured to solve different problems. However, after the war it was rebuilt to operate like any other stored program (von Neumann architecture) computer, as it was the first recipient of the design philosophy seen in the EDVAC report. It operated in that mode from '48 to '55, when it was decommissioned.
ENIAC in Action: Making and Remaking the Modern Computer is an excellent summary of the initial design and redesign of the Eniac.
Apparently Eckert (John Mauchly and J. Presper Eckert designed the ENIAC) claimed that von Neumann basically stole their idea of the stored program and that they had already came up with the idea and he just took it and ran with it as if it was his
EDSAC as early as 1949 had an "initial orders" module. A boot-up ROM. There was a bank of rotary selector switches, to set the octal digits in each ROM word.
David Wheeler (of subroutine fame) figured out the most sensible thing to put in the tiny ROM was a paper tape loader and mini-assembler that loaded the rest of itself from paper tape. So at switch-on the machine would start reading the tape input and run. Programs could be written on the teletype with mnemonics and relative addresses in octal.
It seems a little strange that more advanced later machines like the original PDP-11 from 1970, couldn't "autostart" from ROM like that. You had to toggle in a bootloader.
I think that was because core memory was non-volatile. (EDSAC didn't use core; it had a refreshing DRAM-like delay line memory.) With core, you only had to toggle the bootloader into once and, provided your software didn't accidentally overwrite it, it was still there after a power cycle. So re-toggling in the boot loader was not really that common, despite how much lore surrounds it.
DEC supplied optional boot rom cards for UNIBUS, starting with the BM792, which arrived as a 32 x 16 matrix of diodes. You had to remove some of the diodes by hand to set the boot code.
Later cards used PROMs, and were pretty fancy. The M9312 had 512 words and included some basic CPU diagnostics. Different variants handled boot from disk, paper tape, console, etc, and you had to specify the options you wanted when you bought the card.