Fuses - How Do They Work?

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Complete newbie here. When programming fuses, may they only be programmed one time as in a conventional fuse?

Thomas Blaine Hamrick

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Welcome to AVRFreaks!

 

You can program a fuse many times.

 

Read more about fuses in Microchip Developer Help here.

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The name "fuse" does date from an era when you effectively burned your bridges to configure a device but these days they are like a NAND memory cell (a charge held trapped on the gate of an isolated transistor) but the state can be changed back by a high voltage pump in the device resetting the gate to the 1 state just like you can erase and reprogram any flash. 

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may they only be programmed one time

Generically termed, yes, "programmed" 0/1 as you like.  More technical, erase is classically 1 and "programmed" means 0...so you can erase & program often!

 

When in the dark remember-the future looks brighter than ever.   I look forward to being able to predict the future!

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Firebird246 wrote:
as in a conventional fuse?

As clawson suggests, in the early days they literally were fuses - and, thus, could only be "blown" once, and never "un-blown"

 

The same was true of early PROM.

 

But, nowadays, they are just ordinary Flash/EEPROM - so can be re-programmed (technically, as avrcandies says, "programmed" and "erased").

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I've been blowing a lot of fuses lately.....apparently this is normal when you have a teenager in the house.......winkcheekydevil

 

 

The term 'fuses' with microcontrollers I have noticed has started to become a legacy term.  Some IDE's now call 'fuses' CONFIGURATION BITS.

 

Jim

 

 

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I think it's been legacy for a very long time now?

 

It's not just the IDEs;  some manufacturers just call them "configuration bits" (or similar) in their documentation - presumably those which don't have legacy of having called them "fuses" in the past?

 

In fact, it seems Atmel were phasing-out the term with the SAMs: https://www.avrfreaks.net/forum/where-are-fuses-info-samd21 (although, confusingly, the datasheet does still refer to "fuses" in 6 places!)

 

 

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Agreed. I think "non-volatile configuration bits" would be a good phrase to describe them.

Letting the smoke out since 1978

 

 

 

 

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digitalDan wrote:

Agreed. I think "non-volatile configuration bits" would be a good phrase to describe them.

 

You don't think 'con-fuses' would work just as well?  laugh  S.

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jgmdesign wrote:
The term 'fuses' with microcontrollers I have noticed has started to become a legacy term.  Some IDE's now call 'fuses' CONFIGURATION BITS.

 

Sounds like when I went to a hardware store a couple of weeks back and asked for Jubilee clamps. Took a couple of minutes to explain what I needed, only to be told ahh, those are actually called Hose Clamps. Ummm. no they are not!

Wayne

East London
South Africa

 

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Let me know what a Jubilee looks like when clamped.  S.

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Scroungre wrote:
Let me know what a Jubilee looks like when clamped

 

The Jubilee is a Line: Waterloo stn, Bond str etc. No clamping down possible.

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WayneZA wrote:

... only to be told ahh, those are actually called Hose Clamps. Ummm. no they are not!

 

Jubilee is a brand name for a manufacturer of hose clamps. 

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A copy machine is not necessarily a Xerox machine.

A nasal tissue is not necessarily a Kleenex.

 

That said, however, this is what a clamped Jubilee looks like (It's only a model!)

 

It's a silver bus

and if you can't read the fine print, see also:

Close-up of the silver bus

 

So there!  devil  S.

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Seems "Jubilee" was a brand name a bit like "Hoover" is a name used widely simply to mean "vacuum cleaner"... 

 

https://en.wikipedia.org/wiki/Jubilee_Clip#History

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A van may not be a "Transit".  A ballpoint-pen may not be a Biro, and a vacuum cleaner may not be a Hoover.  If one isn't one, that's grounds for a change in language.  S.

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Same deal.  You could go into a store and say you wanted a Xerox machine.

 

The salespeople might politely let you know that they don't actually have any Xerox machines for sale, but they do have copiers from Brother, Samsung, and Hewlett-Packard.  Would you like a copier?

 

If you continue to insist only a Xerox machine will do, they would be perfectly correct to send you away.  Even if all you wanted was a copier.

 

If you must demand brand name, there may be a reason for that, but demanding brand name for an otherwise acceptable generic item is idiocy.  S.

Last Edited: Sun. Dec 12, 2021 - 01:09 AM
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Well, in thew above example a Hoover may be a brand name and not a device type name, but when they have been called Hoovers for, I don't know, 40 years plus and then suddenly everyone starts calling them Suction Machines and doesn't know what a Hoover is, that's a problem IMO. Old farts like me will probably call them Jubilee clips for the rest of our lives. cheeky

 

There are lots and lots of international and South Africa examples of brand names becoming synonymous with a type of object rather than a manufacturer, and you guys are right that it is a little misleading. However, when basically everyone knows them by that name, don't go and change it to something completely different and not teach people what it was known as for decades before. laugh

 

The reason this hasn't happened as much to Hoover is that they indeed still make vacuum cleaners (yeah, I do use that name instead of Hoover smiley)

Wayne

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Taking this thread even further from its original direction...

 

Where I grew up, "Coke" was the common reference for pop/soda/soft drink.

 

Others I tend to use:

"Scotch Tape" -> adhesive tape

"Sharpie" -> permanent marker

"Velcro" -> hook and loop fastener

"Plexiglas" -> rigid plastic panel

"Q-tip" -> cotton tipped swab

"Jell-O" -> flavored gelatin

 

And living with three grandkids, probably my most abused is "Band-Aid" for an adhesive bandage... with "Google" a close second

David

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There is a knife "Le Douk-Douk" which is so popular that the word replaces "le canif" in the North Africa countries.

Mind, you can use them as a razor. (Do not buy nickel-plated, a standard model will not corrode).

This knife was also notorious for unfair use, for example chasing out French from Algeria fast way.

 

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Some I use:

 

"Vice-grips" (locking pliers)

"Bungee cords" (elastic rope, basically)

"Channel-locks" (adjustable pliers)

"Stanley" knives (box cutters)

"X-acto" knives (more sharp things)

 

Many are still made by the original manufacturer, too, and are often of higher quality than the knock-offs.

 

S.

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Scroungre wrote:
a vacuum cleaner may not be a Hoover.  

It's amazing how many adverts you see on places like FB Marketplace for things like, "Dyson hoover" ...

 

frown

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frog_jr wrote:
"Plexiglas" -> rigid plastic panel

Tends to be called "Perspex" over here - even though that is a brand name.

 

https://en.wikipedia.org/wiki/Generic_trademark

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