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Guide To Designing Low Power Handhelds
randomErr writes "iAppliance had a nifty article about designing handhelds. As the state-of-the-art in low-power CPUs races forward, the CPU becomes one of the most critical components in the design of a handheld. New CPUs such as Intel's XScale, Alchemy Semiconductor's Au1000, and Transmeta's Crusoe provide the ability to scale clock frequency and voltage dynamically. As power consumption varies linearly with clock speed and as the square of core voltage, you'll want to have hardware hooks to be able to adjust both clock speed and voltage as necessary, based on device performance."
I know that the ability to have rechargable batteries is out there, but I've always felt it was somewhat funny that while cordless and cellular phones typically run on batteries that you charge when they're not in use, the PDAs don't come with the same option by default. I wonder why this is, and if in the future that rechargable batteries will be the norm.
Unless these handheld companies can figure how to improve input into these tiny little computers, it doesn't matter how fast the CPU chip is because my big mitts won't get the data into fast enough for it to matter. To me, they are nothing more than a static data storage and regurgitation device, not an interactive system like my notebook or desktop.
Strange women lying in ponds distributing swords is no basis for a system of government.
CPU power is not the issue when it comes to portable computing. The real holy grail will be in acceptable display technology. Whether that be some sort of expanding/folding display technology or a lasar retinal display, something significantly better than our current technology is needed to really make a significant jump in usability and functionality.
I could be wrong, but don't we need a discussion about cooling somewhere? I thought one of the key points to the Transmeta Carusoe chips was the "lower power consumption and therefore lower temperatures and therefore less power needed for cooling so therefore longer battery life." While the whole "fan" issue is a moot point, dont they have to make serious considerations about heat dissipation in handheld devices? Why isn't it dealt with in the article....
When in doubt, parenthesize. At the very least it will let some poor schmuck bounce on the % key in vi. (Larry Wall)
The matter is applicable on heat prevention on laptops: Those out that having a laptop with dynamically activated cpu-fan know the problem. Constantly running processes will activate the fan and increase the noise polution- it doesn't matter if the process is nice or not.
To gain a silent PC we would only need a daemon which constantly checks the CPU-temperature and slows down the system (starting or only from processes with lower priority) to prevent heat and noise.
Not to mention that this would even increase battery-power if only less important jobs are slowed down and thus fan activation is decreased to a minimum.
This really sounds like a neat feature, not complicated to implement- or is there already a project out there dealing with this?
You can have one of these when your handheld draws MICRO-amps, and you carry it around all the time.
It will be about the same time as when your handheld can run for a year off an lithium battery the size of a dime.
Show me the backlight on one of those "self-powered" watches. Oh? They can't even power a backlight? It will be a while...
---"Maybe even some antennae that can absorb all the abundant radio/microwave radiation that cell towers, wi-Fi, bluetooth, high-power transmission lines, the sun, etc. etc. are constantly pumping out? Tesla's wireless power dreams finally realized!"
I like tesla too, and I don't mean that "alien supernatural" stuff you see on the web. Look his patents and you'll find a wealth of RF work on his part. However, something you need to remember about his idea of "portable energy" is that teh signal strength is inversly related to the square of the distance. You're talking about piddiling energy. It'd cost more in energy to MAKE the collector than it would ever get in its life.
I igure this battery life argment will go on ad absurdum. My idea is to use a decent low power chip WITH 2 redundant power cells (9 volt?). If 1 dies, the other one takes over. You would be able to "hot swap" batteries. Just go into a store and buy 1. Or ytou could use LiIon batteries. They're a bit more reliable for correct voltage. But when they die.....
I see a problem with voice recognition. It is not the technology itself, but more of where you can use this method. Imagine yourself in a classroom, where all of the students are talking to their PDA, to take class note.
I think a quiet (less dirturbance to the environment) input method is required. Voice is just not the one.
Which do you think is more cost-effective for a software company?
1) tell all their programmers to spend lots of time optimizing their code-- probably making it faster but harder to debug and maintain
OR
2) wait for AMD and Intel to cook up a new batch of microprocessors
If you guessed #1, you just lost. Guess what? Assembly langauge programming was faster, but it died out because (software) optimization stopped being a priority. Already C is starting to look archaic (except maybe for systems-level programming).
The reality is, software in the future will be buried under more and more layers of abstraction, just because it's easier that way. Easy to use, commercialized high level languages like Java are the future.
P.S. Please no flames about compilers vs. human assembly language programmers. Most of the binaries you run are probably compiled for a 386 anyway, if you use linux.
"Any connection between your reality and mine is purely coincidental." -Slashdot
A handheld is not supposed to replace a computer. It's supposed to provide useful functions like keeping to-do lists, schedules, phone directories, unit conversion programs, notes, etc. A good handheld design is a carefully engineered compromise between battery life, features, and speed. That's something that Palm and Handspring have pretty much understood. Only when Microsoft entered the market did people start demanding that handhelds come with 200mhz CPUs, ooh-gobs of RAM, and displays that ran the color spectrum from UV to IR.
A handheld is not an MP3 player. It's not a tiny laptop computer. It's not supposed to run X-Windows, FTP, or a web server. It's not supposed to be used for SETI at home, factoring huge primes, or playing first-person shooter games. I want month-long battery life, not a handheld with a heatsink and 10,000rpm fan. Don't screw up the market by demanding things that sway manufacturers to sell toys for geeks rather than tools for professionals.