They're also awesome. Think of them like the AVR or PIC with more.. everything. More RAM. More ROM. More IO. More interfaces, both type and quantity. More Hz. Same price, they work with GCC.
I've been getting STM32s from china for cheaper than the basic AVRs on an arduino (not sure how, as even qty 1000 is like 4x the price on digikey, but they work like the real thing, so who knows?!).
I used to love AVRs, but whenever I go back to them now, they seem so limited. the ARM MCUs have a bit of a learning curve, but it's so worth it. With GCC and libopencm3, it's an entirely open source setup. The nucleo boards are dirt cheap arduino-ish things, to get started on, with integrated programmer & debugger.
There's really no reason to use 8bit MCUs anymore, unless you're making a $0.40 gadget, and need to squeeze out that last nickel.
Price. Why spend $4 where $0.05 will do, and will likely never fail anyway? It's a last ditch protection system, not really something that should be tripping all the time.
That said, it used to be fairly common to have breakers on a couple circuits (headlights, for one).
In addition to cost, I'd suppose reliability might be a second consideration. Breakers have contacts in them, which with enough vibration and temperature/humidity cycling might fail, I guess... whereas a fuse has none.
What else.. fuses are faster, better current breaking capacity for DC (at least at this price point). I'd guess the tempco might be better too. (the trip point both devices moves with ambient temperature).
That's how it generally works already. Important stuff is on one CAN bus (ECU, ABS pump, auto trans controller if it has auto trans, airbags, etc). All the secondary stuff like door modules (controls locks, windows, etc), cabin illumination, the radio/navi and whatnot are on a secondary CAN bus (or LIN, or..).
This way if your rear door module dies and manages to take down the (secondary) bus, the car still runs.
I don't see much point in securing it, as you need physical access anyway. I'd rather see it go the other direction, standard, open interface, instead of each manufacturer using a proprietary communication scheme. (CAN only defines lower layers).
This is like suing computer makers for people being able to hack a computer they have physical access to. It's not possible to prevent.
Here's the rules, FWIW. Pennies are only valid to 25c.
(2) A payment in coins referred to in subsection (1) is a legal tender for no more than the following amounts for the following denominations of coins:
(a) forty dollars if the denomination is two dollars or greater but does not exceed ten dollars;
(b) twenty-five dollars if the denomination is one dollar;
(c) ten dollars if the denomination is ten cents or greater but less than one dollar;
(d) five dollars if the denomination is five cents; and
(e) twenty-five cents if the denomination is one cent.
Short notes: Fancy NiCd, Higher density and sealed. They rely on precise chemistry to be hermetically sealed units (lean on one element, for limiting and only O2 production). High pressure at full charge (~60PSI at room temp), higher if things go south, Pressure drops with charge state. Excess discharge causes hydrogen production.
So, tin can, pressure changing with charge cycles (metal fatigue over many cycles?), H2 production, O2 production... maybe there is some chance for catastrophic failure there.
Though the units in question do have batteries, which have historically been of the NiCd variety, and are in this case as well. I'm not sure if any newer satellites use newer battery tech? (NiMH or some sort of lithium ion..).
I'd imagine more harmful to ingest/inhale uranium ore... in addition to radioactivity, uranium is also a heavy metal like lead. (in both senses of the term "heavy metal".)
However most ore is quite weak, with 1% being pretty decent... I think it's economical to mine it as low as 0.1%. A few mines in Canada are near 20%, though (which I suppose is related to Canada being the biggest producer... 1/5th the ore is end product, instead of 1/1000th!). Ore will often have lead and such in it as well (decay products), which is also toxic.
It might be different in the US, but in Canada they always had terrible stock. So if your thing didn't have a broken lamp or speaker, or a dead battery - you were SOL, as they didn't carry anything else.
There's so much different silicon now that it isn't really feasible to stock even a small portion of it in every mall anyway, so most anything you fix you'll have to order in parts for...
It would have been more reasonable when I was a kid (and they only stocked a whopping 3 transistors and zero fets then, too).
FWIW, the Audi dealer still lists... must be at least 95% of the parts for my 80's audi, down to the nut. I don't think any american marque does that..
Of course they charge you for it, but they do carry it.
Lithium cells are pretty benign in general. There are a few variants in chemistry, the worst would probably be the cobalt based ones. (others use various combinations of iron, nickel, manganese, and phosphorous, which are pretty tame). Though the cobalt variants are quite common.
NiCd is far worse, cadmium is fairly nasty... much more than cobalt.
In every 'dead' laptop battery I've torn down, one cell (or pair, in parallel) is totally kaput, and the remaining cells retain at least 50% of their nameplate capacity. Protection circuitry will lockout recharging of the whole pack, which wouldn't work with the dead cell anyway.
So the battery as a whole is utterly useless for the laptop, but 2/3rds of the cells or more have some life left in them, for other purposes.
I imagine a lot of the too-cheap-to-be-true off-label replacement laptop batteries are in fact combinations of two dead ones, with the remaining functioning cells rewired into one working (but lower capacity) pack. Certainly seems about right judging by the performance of them, anyway.
Slashdot Mirror
Because the militarization of police in the US.
I love Geany. There's a windows port as well, if people aren't aware of it.
They're also awesome. Think of them like the AVR or PIC with more.. everything. More RAM. More ROM. More IO. More interfaces, both type and quantity. More Hz. Same price, they work with GCC.
I've been getting STM32s from china for cheaper than the basic AVRs on an arduino (not sure how, as even qty 1000 is like 4x the price on digikey, but they work like the real thing, so who knows?!).
I used to love AVRs, but whenever I go back to them now, they seem so limited. the ARM MCUs have a bit of a learning curve, but it's so worth it. With GCC and libopencm3, it's an entirely open source setup. The nucleo boards are dirt cheap arduino-ish things, to get started on, with integrated programmer & debugger.
There's really no reason to use 8bit MCUs anymore, unless you're making a $0.40 gadget, and need to squeeze out that last nickel.
At least the dust is less toxic these days.
That's a myth. Asbestos based linings were never banned, and still exist.
I learned that a couple years ago. I swore it was banned too, but it isn't the case.
There are roughly 8.7 Wales to an Oklahoma.
Price. Why spend $4 where $0.05 will do, and will likely never fail anyway? It's a last ditch protection system, not really something that should be tripping all the time.
That said, it used to be fairly common to have breakers on a couple circuits (headlights, for one).
In addition to cost, I'd suppose reliability might be a second consideration. Breakers have contacts in them, which with enough vibration and temperature/humidity cycling might fail, I guess... whereas a fuse has none.
What else.. fuses are faster, better current breaking capacity for DC (at least at this price point). I'd guess the tempco might be better too. (the trip point both devices moves with ambient temperature).
That's how it generally works already. Important stuff is on one CAN bus (ECU, ABS pump, auto trans controller if it has auto trans, airbags, etc). All the secondary stuff like door modules (controls locks, windows, etc), cabin illumination, the radio/navi and whatnot are on a secondary CAN bus (or LIN, or..).
This way if your rear door module dies and manages to take down the (secondary) bus, the car still runs.
I don't see much point in securing it, as you need physical access anyway. I'd rather see it go the other direction, standard, open interface, instead of each manufacturer using a proprietary communication scheme. (CAN only defines lower layers).
This is like suing computer makers for people being able to hack a computer they have physical access to. It's not possible to prevent.
That's also how ethernet works... differential transmit and receive signals, transformer coupled for isolation. (to prevent ground loops and such).
Shutting off all the electronics on a fly-by-wire plane seems like a fairly bad idea.
Here's the rules, FWIW. Pennies are only valid to 25c.
(2) A payment in coins referred to in subsection (1) is a legal tender for no more than the following amounts for the following denominations of coins:
(a) forty dollars if the denomination is two dollars or greater but does not exceed ten dollars;
(b) twenty-five dollars if the denomination is one dollar;
(c) ten dollars if the denomination is ten cents or greater but less than one dollar;
(d) five dollars if the denomination is five cents; and
(e) twenty-five cents if the denomination is one cent.
These ran NiCd cells. Here's some TL;DR from NASA about a variant of NiCd they use(d), not sure if it applies here.
http://www.nasa.gov/offices/oc...
Short notes:
Fancy NiCd, Higher density and sealed. They rely on precise chemistry to be hermetically sealed units (lean on one element, for limiting and only O2 production).
High pressure at full charge (~60PSI at room temp), higher if things go south, Pressure drops with charge state.
Excess discharge causes hydrogen production.
So, tin can, pressure changing with charge cycles (metal fatigue over many cycles?), H2 production, O2 production... maybe there is some chance for catastrophic failure there.
http://en.wikipedia.org/wiki/R...
Though the units in question do have batteries, which have historically been of the NiCd variety, and are in this case as well. I'm not sure if any newer satellites use newer battery tech? (NiMH or some sort of lithium ion..).
they even try to steal live high-tension lines. which are aluminum around a steel core, nothing there but electrocution, folks.
Aluminium is 30+ cents a pound, that's enough to buy some glass. They'll have to steal 10x as much to make the same money, but...
Many do... but not Russia, which happens to be where the guy is.
It's thinned about 25-50% with naphtha so that it flows. "diluted bitumen".
LiFePO4 would be well suited to things like cordless tools and the like. iDrill?
There's no switching (or otherwise) power supply in a SD card though. Not much of anything other than flash and a controller.
I'd imagine more harmful to ingest/inhale uranium ore... in addition to radioactivity, uranium is also a heavy metal like lead. (in both senses of the term "heavy metal".)
However most ore is quite weak, with 1% being pretty decent... I think it's economical to mine it as low as 0.1%. A few mines in Canada are near 20%, though (which I suppose is related to Canada being the biggest producer... 1/5th the ore is end product, instead of 1/1000th!). Ore will often have lead and such in it as well (decay products), which is also toxic.
It might be different in the US, but in Canada they always had terrible stock. So if your thing didn't have a broken lamp or speaker, or a dead battery - you were SOL, as they didn't carry anything else.
There's so much different silicon now that it isn't really feasible to stock even a small portion of it in every mall anyway, so most anything you fix you'll have to order in parts for...
It would have been more reasonable when I was a kid (and they only stocked a whopping 3 transistors and zero fets then, too).
Though it requires active cables, which cost quite a bit more. So it might have a place for bleeding edge stuff, but not so much for economy.
FWIW, the Audi dealer still lists... must be at least 95% of the parts for my 80's audi, down to the nut. I don't think any american marque does that..
Of course they charge you for it, but they do carry it.
This is not Canada bending over for Amerika, It's Harper saying "Screw you" you're not going to threaten Canadians.
Bullshit. Harper lives to bend over for Americans. He'll do it without them even asking.
I'm not british and like jaffa cakes. orange and chocolate is an awesome combination.
Lithium cells are pretty benign in general. There are a few variants in chemistry, the worst would probably be the cobalt based ones. (others use various combinations of iron, nickel, manganese, and phosphorous, which are pretty tame). Though the cobalt variants are quite common.
NiCd is far worse, cadmium is fairly nasty... much more than cobalt.
In every 'dead' laptop battery I've torn down, one cell (or pair, in parallel) is totally kaput, and the remaining cells retain at least 50% of their nameplate capacity. Protection circuitry will lockout recharging of the whole pack, which wouldn't work with the dead cell anyway.
So the battery as a whole is utterly useless for the laptop, but 2/3rds of the cells or more have some life left in them, for other purposes.
I imagine a lot of the too-cheap-to-be-true off-label replacement laptop batteries are in fact combinations of two dead ones, with the remaining functioning cells rewired into one working (but lower capacity) pack. Certainly seems about right judging by the performance of them, anyway.