the peril of settings

[Jurek]

Richard Feynman reportedly said "If you think you understand quantum mechanics, you don't understand quantum mechanics,” and he wasn’t joking. Speaking of which.


Bananas: they just work

Using a Biro on a bananananana is exceptionally satisfying.
ETA: And yes, that's the end which monkeys open them.

But:
There is nothing better in life
Than writing on the sole of your slipper with a Biro.

It is a similar experience to that of using a ballpoint pen to write on bananas.

[Cudzoziemiec]

Perhaps I should make that a more high-level question: how on earth do 'silicon chips' store things? What happens when something is 'remembered' on one?

The lies-to-children version of the main flavours of computer memory:

I hope you enjoyed writing that – and I expect you did!

Right, I've got my own geek analogy in my mind now. It's like old-fashioned hump-shunting railway waggons, where you push them all up to the top of the hump then as they trundle down the other side under gravity, switches are switched and points are pointed in such a way as to make all the coal trucks go to the coal train, all the blue trucks to Thomas and all the carriages with dangly bike spaces to the train that goes where all the short people live. Except we've only got two sorts of truck, and they are truck and no-truck, one electron being identical to any other electron. But we've got a series of switches that sort out trains of electrons. And then these trains of electrons don't actually go anywhere, they just get announced: the train now standing at platform one is a letter black pixel. I think it's that interpretation bit I want to understand but let's leave that for another day.

[Kim]

Perhaps I should make that a more high-level question: how on earth do 'silicon chips' store things? What happens when something is 'remembered' on one?

The lies-to-children version of the main flavours of computer memory:

I hope you enjoyed writing that – and I expect you did!

Right, I've got my own geek analogy in my mind now. It's like old-fashioned hump-shunting railway waggons, where you push them all up to the top of the hump then as they trundle down the other side under gravity, switches are switched and points are pointed in such a way as to make all the coal trucks go to the coal train, all the blue trucks to Thomas and all the carriages with dangly bike spaces to the train that goes where all the short people live. Except we've only got two sorts of truck, and they are truck and no-truck, one electron being identical to any other electron. But we've got a series of switches that sort out trains of electrons. And then these trains of electrons don't actually go anywhere, they just get announced: the train now standing at platform one is a letter black pixel. I think it's that interpretation bit I want to understand but let's leave that for another day.

Train analogies aren't bad once you go up a layer of abstraction and stop worrying about the electricity and start thinking  about bit streams.  A hump-shunting yard isn't a bad analogy for a shift register - a type of memory that's frequently used for converting a series of bits on individual wires (parallel data) to one bit at a time over a series of clock cycles^[1] (serial data), or vice-versa.  Sort of thing a CD player might use to turn that stream of 1s and 0s from the FRIKKIN LAZER into a byte at a time to represent voltages for the digital-to-analogue converter.


_{[1] We haven't talked about clock cycles yet.  They're important because it takes time for all this circuitry to settle when something changes state, and if the input of one thing is connected to the output of something that's still in the process of changing from 0 to 1 things can get a bit wibbly.  So you have a clock, ticking out pulses so things only change when there's a new pulse.  This is, like so many things in life, best portrayed through the medium of interpretive dance.}

[Mr Larrington]

What exactly is 'flash' memory and why is it called 'flash'? This is the kind of question which, when answered, is liable to leave me my informed but unenlightened, but I'm asking it anyway.

In even more laymans terms, it doesn't remember what you put in there (as Ian says, "volatile").  We're currently trying to document for a customer that all the non-volatile memory (other than the obvious stuff, like hard drives) in one of our systems isn't capable of revealing their secrets should someone else get hold of it.

Long long ago in a data centre far far away* The Mgt decided some, or more, of our VAXen needed MOAR RAM.  The easiest way to do this was to take out the old memory boards, install new ones with the more capacious chips and flog the old ones on eBay back to DEC.  “Wait… WHAT!” exclaimed a Very Senior IT Manager.  “Suppose the new owners plug it in and start reading OUR data?  No, they'll have to be smashed up with hammers, then burned.  And the ashes fired into the sun!**”  The professionals eventually managed to pummel the concept of volatile memory into his skull, but apparently it took a very long time.

* SE1
** This bit may contain traces of Lie

[ian]

I was once terribly mocked by a gang of uncouth Brazilians for opening a banana wrongways. To this day, I still can't look at a banana without thinking of that moment.

[PeteB99]

Until a few posts ago I had no idea there was a right or wrong way to open a banana. Why?

I've always opened them from the stalk end.

[sam]

Until a few posts ago I had no idea there was a right or wrong way to open a banana.

There's no shame in it. It's something passed down from monkey to monkey.

[PeteB99]

Ah It's a monkey thing is it?  That explains a lot. I'll add it as a footnote to the report I'll take back to my home star system.

[ian]

The stalk is where the banana's butt is. Probably.

It's just easier, the stalk lets you hold the banana so you don't get sticky fingers at the end.

[Mr Larrington]

You mean you ent got one o' these?



Standards are slipping.

[rafletcher]

The stalk is where the banana's butt is. Probably.

It's just easier, the stalk lets you hold the banana so you don't get sticky fingers at the end.

But you do get a mouthful of bitter skin to start off with.

[ian]

No, you pop the seam at the top, while checking carefully for banana spiders.

[JennyB]

No, you pop the seam at the top, while checking carefully for banana spiders.

FWIW that''s what the monkeys and apes I've known do. Baboons use their teeth; chimps use their nails. With a bit of practice you can doo it one-handed and the skin you leave still looks like it has a banana inside. 

[Davef]

You have to be quite careful removing the banana from the bunch not to accidentally open it the difficult way.