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Comment by jmbwell | Hacker News Reader

I always thought 'flash' was a holdover from early reprogrammable ROM technology, non-volatile memory that you could erase by literally flashing a literal flashbulb over a little window on the chip. I would've sworn in a court of law that I recall this being called "flashable" memory, that erasing it was called "flashing" it, and reprogramming it in general was called "reflashing" in a sort of synecdoche. And I'd have assumed that this was the fundamental origin of what became _electronically_ erasable ROM (EEPROM), which led to all the various NVRAM technologies we have now, with "flashing" sticking as the term for reprogramming it, even after you could do it electronically.

It looks like the story these days is that someone at Toshiba thought up the name out of the blue. I'm skeptical!

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> holdover from early reprogrammable ROM technology, non-volatile memory that you could erase by literally flashing a literal flashbulb

No. I can see how that might appear plausible but they're unrelated. Flash was a marketing term invented to differentiate a new EEPROM technology that allowed much higher density, and featured sector erase, from previous EEPROM tech. This was done because engineers saw EEPROM as esoteric expensive tech that had no place in low cost products. The Flash vendors wanted to position the new chips as replacing UVPROM, which was relatively cheap by comparison. So they came up with a name that was a) not EEPROM and b) conveyed that the devices were quickly reprogrammed vs UVPROMs (which had to be baked in an eraser then took some minutes to program in a special piece of equipment).

Flash's big advantage was that it could be programmed on-board, allowing soldered down PROMs, surface mount packages.

Source: I was a hardware design engineer when Flash was introduced and heard the marketing pitch first hand.

Using Flash chips for rewritable bulk persistent storage came much later. The first generation devices didn't have the necessary density.

I never heard of using a literal flash to reprogram EPROMs, but this wikipedia entry[1] makes your story for the origin of the term “Flashing” seem likely

EPROMs are easily recognizable by the transparent fused quartz (or on later models resin) window on the top of the package, through which the silicon chip is visible, and which permits exposure to ultraviolet light during erasing.

[1] https://en.m.wikipedia.org/wiki/EPROM

It does look like all the references I can find point to engineers at Toshiba in 1980 coining the name, although Google ngrams shows some references to "flash EPROM" prior to 1980, so I can't help but wonder if the idea existed at least in some form prior to 1980

Looking into it, those references look miscategorized. It's some Zambian national report that's talking about 0.18um processes (aka, 180nm) in the same paragraph, which wouldn't have come out until the very late 90s.

These things were used in a number of computers from the early 90s, I have a few lying around for my Amiga.

Heard from a greybeard that they had a demo night in university (this was probably early 80s), and one of the demos was was some sort of path-finding rover robot. Of course, it ended up being one of those projects that had show stopping bugs up until a few hours before showtime.

During demo night, it was a big hit, until a stray camera flash got (un)lucky and wiped the microcontroller's EEPROM...

Feels a little apocryphal (I'd assume most flashes have / had UV filters?)

This still happens today. Some chip packaging doesn't provide enough protection from UV.

https://forums.raspberrypi.com/viewtopic.php?f=28&t=99042

You would have put some tape over the window to keep that from happening.

Also erasing takes like 15+ mins, it wasn’t quick.

EPROMs were erased by many minutes of exposure to UV light, not a flashbulb, in a device called a UV eraser. I've never heard anyone refer to any operation on an EPROM as "flashing".

Yep, "UV eraser" confirmed by an elmer I know. A unit with a drawer and a timer knob, he says you'd typically set for 30 minutes.

He says he does recall people calling it "flashing," but not until much later, by which time it would have been actual "flash" memory.

As for my own memory, I'm going to file this under Mandela Effect, cross-referenced under Things People Probably Told Me That I've Believed Since Before The Internet Was Available To Fact-Check!

Note that the Internet isn't always right, and sometimes the dead trees are the only reliable source.

The Mandela Effect is just a name we've come up with for identifying biological memory faults.

Still own and use a little 9V plastic “portable” UV EPROM eraser that I’ve had for 30 years. Never heard the term “flashing” in this use even when I used them commercially. It really makes no sense what it has to do with flashing, it’s a steady gas discharge lamp for 10 to 20 minutes.

The process of programming EPROM was colloquially called “burning” whereas for Flash the programming is called “flashing”, despite the characteristic that the name originally refers to is fast erase speed.

I always thought that "flash" memory was named for EEPROM's erase speed compared to EPROM erase speed (less than a second versus 20+ minutes).

EPROM has erase as the first word in the acronym, so everyone just said "erasing" the PROM when they put the chip in the UV eraser.

Wikipedia lists finer differentiation between flash memory and EEPROMs.

see https://en.wikipedia.org/wiki/EEPROM#Related_types

Programming the windowed EPROMS was called burning. Don't ever recall hearing anything about flashing them for programming or erasure.

Yeah, exactly. 'Burning' itself being a holdover from PROMs, where you'd literally burn certain fuses in the array to select bits.

/pedantic

ROM - Read Only Memory - programmed at the time of manufacture.

EPROM - Erasable Programmable Read Only Memory (AKA UVEPROM because they could be erased using UV light over a period of time, and they had a quartz window to admit the UV.)

EEPROM - Electrically Erasable Programmable Read Only Memory. IIRC it required a special device to erase.

It's been a while since I worked with this stuff but I don't ever recall hearing it called flash.

Actually no, it’s Toshiba trademark for then-new type of EEPROMs that could be erased quickly in blocks rather than having to be set and unset bit by bit.

Intel had italic stylized “FLASH” logo proudly printed on chips. I’ve come across it once.

Old-school windowed EPROMs need to be erased under a UV-C tube for something like 20 minutes. By comparison a flash memory block erase operation is practically instantaneous.

Anecdotally this was also what was told to me by (now retired) electronic engineers who worked in automotive embedded systems in the 80's/90's. The term flash was related to the process of UV exposure to erase memory. This was also humorously explained to me as the beginning of the end for system performance. You didn't need to prove out your system when you could just update your hardware after the fact. In a world of over-the-air flashing we have come a long way from fixed design elements.

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