ARM's ultra-low-power fridge-puter chips: Just what the CIA ordered
'He's just had a Scotch egg, sir' 'Ha! I knew it!'
Prototypes of a new tiny, ultra low-power ARM-licensed processor will be demonstrated at an engineering conference in California next week. The chips are so small and energy efficient that they're aimed at wirelessly hooking up kitchen appliances, light bulbs and 'leccy meters to your network. And to the CIA.
Will this lead to sassy fridges ordering you to lose weight, based on your diet of crappy food, or intelligent heart-rate monitors advising you to stop reading about infuriatingly pointless shleb shenanigans in the news? Our fingers are crossed.
However, one group that certainly thinks it'll benefit massively from a surge in smart sensor proliferation is the world's spying organisations.
ARM Cortex-M0+ enter stage left
The concept of a smart home, or smart hospital ward, kitted out with tiny sensors is comfortably at least a decade old. By gluing microcontrollers (MCUs) to a bunch of detectors and wrapping them up in radio circuitry, you've suddenly got yourself intelligent little data broadcasters reporting back to a central decision-making storage hub.
There are plenty of tiny and very simple 8- and 16-bit microcontrollers out there to do this – but ARM thinks it can do better than everyone else in the low-power world and is determined to park its electric golf cart on the MCU industry's lawns. The Cambridge-based chip designer wants to take its powerful 32-bit architecture and drive it down to levels of power consumption enjoyed by more primitive 8-bit silicon, thus tempting engineers onto ARM's new Cortex-M0+ chips.
The M0+ follows the Cortex-M0 down the path of embedded simplicity. It uses ARM's compact Thumb instruction set; a rather barebones two-stage pipeline along which program code is fetched and executed; faster IO and flash memory access than before; an optional primitive memory protection unit that most manufacturers will leave out; and has added other speed and power tweaks to the design. There's no floating point unit although a ROM provided alongside the core can feature a maths library to provide routines for performing complicated calculations.
There's none of the huge cache, massive pipelines, multiprocessor interconnections, convoluted code execution reordering and other architectural bulk that weighs down Intel's powerhouses; the M0+ design starts off with just 12,000 gates. According to ARM CPU product manager Thomas Ensergueix, it's a completely new design started from scratch to push his company's platform further into the ultra low-power embedded world with minimal baggage.
These cores are expected to be wrapped up in flash and RAM in the order of scores of kilobytes, driven by a clock frequency of at most 50MHz, and draw 9 millionths of an amp per MHz on a 1.2V supply. The floor-plan area – the size the core will take up on a silicon die – is about a millimetre square, and it will cost manufacturers about 20 pence per core in royalties to ARM, we're told.
ARM's performance graph for the Cortex-M0+ compared to rival microcontroller cores. The graph represents just the code executing core and flash memory, using figures advertised by the rival manufacturers. The graph represents CoreMark benchmark performance per nano amp of current drawn.
Speaking to The Reg, Richard York, director of product marketing at ARM, said the 32-bit processor is aimed at embedded applications that need a bit more number-crunching power and perhaps more memory and interfaces, and better debugging support as embedded software complexity increases.
He argued that the amount of information that needs to be transferred can be reduced by using the extra processing oomph to massage raw sensor data in-core before transmitting it: this should further cut power requirements because broadcasting over the air is a significant current draw compared to what's consumed by the code-executing silicon gates.
Seasoned engineers told El Reg they are skeptical of this bold claim, arguing that once you throw in the communications software stack and protocols, the transmission overhead wipes out any power saving from sending 10 bytes instead of 200.
However in the case of a dumb microcontroller spraying a stream of, say, temperature readings to a larger decision-making computer, the benefit of replacing this component with a beefier chip that can turn around this data into a single packet to say "please turn off the heating" is more obvious. It's a delicate balancing act of power consumption in a technology scale where even the way a chip is wired up to the circuit board makes a significant difference.
York pointed towards Ember's ZigBee system-on-chips – which pack a Cortex-M3, 128KB of flash, 12KB of RAM and wireless personal networking circuitry – as an example of technology that can "cook data rather than leave it raw", maximising the efficiency of data transmission while maintaining portability. A hospital would prefer to strap tiny, wearable smart sensors to patients than have them tethered to heavy monitoring equipment, he said, as doctors "would rather have patients walking around than always strapped to a bed".
Ok, I'll bite...
Why the hell would I want any of my kitchen appliances online? I mean, really...
I can't load my laundry remotely anymore than I can take it out and hang it up remotely. So why does my washing machine need an internet connection? It already has a timer, so I can load it up and set it to finish around the time I'll be home.
Why does my dish washer need to be online? I switch it on when it's full. And if I can't fill it remotely I'll always be there at the moment it does become full.
I don't need to constantly adjust the thermostat in the fridge either - I do that maybe twice a year: right before I go on holiday, and right after I come back.
Taking food out the freezer and sticking it in the microwave is the simplest form of 'cooking' there is and I rarely do that. (If you can even call it cooking - it's more like the barest form of survival if you ask me.) And even if I did, I certainly wouldn't be able to do it remotely.
So why? Why do we need these things connected to the net? Really, I want to know...
Re: Kitchen Appliances
If they aren't connected to the net how are they going to download security updates and anti-virus software?
"...in an age when parents set up Twitter and Tumblr accounts for their newborns...."
Just when I think things cannot possible get more mind-bendingly idiotic than they already are, I see something like that.
Has someone been replacing the Kool-aid with Brawndo?
"Items of interest will be located, identified, monitored, and remotely controlled"
So says "King" David Petraeus, the guy who managed to lose track of about 190'000 freshly imported AKMs in Iraq. Oh well. [http://www.washingtonpost.com/wp-dyn/content/article/2007/08/05/AR2007080501299.html]
Let us conclude with the following gem. Guess by whom:
Back in the kitchen he fished in his various pockets for a dime, and, with it, started up the coffeepot. Sniffing the – to him – very unusual smell, he again consulted his watch, saw that fifteen minutes had passed; he therefore vigorously strode to the apt door, turned the knob and pulled on the release bolt.
The door refused to open. It said, "Five cents, please."
He searched his pockets. No more coins; nothing. "I'll pay you tomorrow," he told the door. Again he tried the knob. Again it remained locked tight. "What I pay you," he informed it, "is in the nature of a gratuity; I don't have to pay you."
"I think otherwise," the door said, "Look in the purchase contract you signed when you bought this conapt."
In his desk drawer he found the contract, since signing it he had found it necessary to refer to the document many times. Sure enough; payment to this door for opening and shutting constituted a mandatory fee - not a tip.
"You discover I'm right," the door said. It sounded smug.
From the drawer beside the sink Joe Chip got a stainless steel knife; with it he began systematically to unscrew the bolt assembly of his apt's money-gulping door.
"I'll sue you," the door said as the first screw fell out.
Joe Chip said, "I've never been sued by a door. But I guess I can live through it."
I won't be getting another smart fridge.
My last one killed itself. It left a note. Sait it was tired of feeling so empty inside.