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When did supercapacitors start being used in consumer products?
Ranayna:
--- Quote from: Andy Chee on January 07, 2024, 06:59:15 am ---
--- Quote from: Shonky on January 07, 2024, 06:15:09 am ---
--- Quote from: Andy Chee on January 05, 2024, 04:31:51 am ---
--- Quote from: Shonky on January 05, 2024, 03:37:33 am ---Don't need a supercap to store settings.
--- End quote ---
This VCR was built in an era when 4-bit microcontrollers were "a thing" (the chip in the image is a 4-bit micro). In other words, flash and eeprom were an expensive luxury, they couldn't even afford 4 extra bits!
The supercap retaining power to the 4-bit micro was evidently a cheaper way to retain memory settings.
--- End quote ---
The question was why 21st century devices can't remember settings implying a supercap could do it.
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The answer almost always comes down to cost, rather than any technological constraint.
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Most likely reason.
Also, i addition to the super cap to store the settings, depending on what these settings actually are, you might need to implement a way to reset the device to factory default if they get corrupted somehow.
joeqsmith:
We started using them in the mid 80s, when ever NEC started to offer them. I think I still have a few of the early ones.
Siwastaja:
--- Quote from: Shonky on January 05, 2024, 03:37:33 am ---Flash or EEPROM can easily
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In 1980's, you didn't have those - so battery-backed SRAM was the usual way. They managed to build low-power SRAM so even small batteries lasted for years. Supercapacitors this early was news to me, too.
BTW, battery-backed SRAM is still a thing, for example most STM32 MCUs have this feature. It's quite useful for some stuff, without having to think about erase/write times or endurance.
Halcyon:
--- Quote from: Alex Eisenhut on January 05, 2024, 02:52:32 am ---(If so... why can't 21st century stoves, microwaves, and fridges, etc recall their dumb settings when a single cycle of AC goes missing?)
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This shits me about my oven (and it's not a cheap model/brand either).
At least if you're going to have a product that forgets the time, have it fail to a known and predictable state. For example, my Sharp microwave defaults back to a scrolling Welcome/Demo message and after you use the product for the first time (but don't set the clock), it just shows a static "0" when not being used. This is sensible.
My oven on the other hand starts flashing the time and starts counting again from 00:00, so that it's always showing the incorrect time until you manually reset it. I would rather the display be completely blank or just flash a decimal point or something.
coppice:
--- Quote from: joeqsmith on January 07, 2024, 09:39:04 pm ---We started using them in the mid 80s, when ever NEC started to offer them. I think I still have a few of the early ones.
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NEC started offering modern style supercaps in the late 70s. I think their primary target market at their launch was backup which was just becoming a substantial market at that point. This was before EEPROM was really viable for cheap backup.
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