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The thing is, renewable energy is only uneconomical until it's not. Science and technology progress - pretending something won't ever work because it doesn't today is a dangerous line of thinking.

Progress comes in random spurts - but it always comes: http://www.digikey.com/Web%20Export/techzone/energy-harvesting/article-2011july-solar-cell2.jpg

Your ultracaps are right on over here: http://www.digikey.com/product-search/en/capacitors/electric-double-layer-capacitors-supercaps/131084

I don't think the submitter is asking about the optical-stereo kind of 3d (like what you get with "3d movies" and "3d glasses"), but rather just geometric projections of 3d scenes onto a 2d viewing plane, like you get in Leonardo da Vinci paintings or Quake.

PDF can do this. Adobe's viewer can do it for sure. Chrome's internal PDF viewer seems to choke on it. Not sure about other software. It doesn't seem to be an Adobe-only feature. Digikey uses it for some of their parts. Digikey CP-102A-ND is a decent example.

I never understood the point. Splice a parallel port to a bread board and hook it to any beige box PC that folks are literally giving (or throwing) away. They're better than the Raspberry Pi in every way except size. You can hook a LED (maybe w/ resistor) directly to many of the pins of the parallel port and they light up representing the individual bits. IO doesn't have to be serialized and deserialized, so you don't have to use a RS232 or any other integrated circuit chips. The beige box also supports Serial and Universal Serial Bus (USB), not to mention a 56k Modem. Old beige box has more RAM, more peripherals, EASIER to work with parallel interface for hardware. Man, I swear. If I spray painted them brown and called them "Chocolate Quaternion" people would be buying them just as fast as the Raspberry Pi were it to get the same level of press. I mean, it's like the folks buying these don't even search around for ways to do hardware projects with the machines they've got or even look for other single board computers before buying one due to all the damn press the Raspberry Pi gets. I mean, $25 is great, but there's other options with various speeds and features at other prices. It's not the only $100 computer with a nice IO header, damn. Seriously.

I thought the 8086 through 80386 just went out of production in 2007.

By Intel, I would assume. That doesn't stop them from still being produced. Here's the 8086 and 8088.

http://www.digikey.com/product-detail/en/CP80C86-2Z/CP80C86-2Z-ND/1976070
http://www.digikey.com/product-detail/en/IP80C88/IP80C88-ND/1063276

I thought the 8086 through 80386 just went out of production in 2007.

By Intel, I would assume. That doesn't stop them from still being produced. Here's the 8086 and 8088.

http://www.digikey.com/product-detail/en/CP80C86-2Z/CP80C86-2Z-ND/1976070
http://www.digikey.com/product-detail/en/IP80C88/IP80C88-ND/1063276

How, without a redesign of the board and without using a larger MCU?

I can understand that more features require more memory, and they cost more too. But that is counter to the mantra of IPv6 proponents that the change is easy and it costs little. There are millions of Polycom IP phones out there that can only talk IPv4, for example. They cannot be upgraded.

Cost of those little chips cannot be disregarded either. The 128 kB part is $6.99 but a similar 512 kB part is $9.79, a 40% increase. The price of your product will go up by a few percent because of that. Doing that during recession, with US labor and associated costs (taxes) already going through the roof will kill a few thousand more US jobs across the industry through reduction of sales.

If you happen to buy regularly from Digikey, this one might work for you @ $6.40 plus shipping.

I used a PandaBoard in a robotics project recently. It's pretty powerful and full-featured, though it costs $182.

That's what technology like PCM is for. As you shrink the lithography, PCM purportedly gains in reliability due to the reduced amount of material needed to actually store the bit.

That and, unlike memristors, you can actually buy PCM now, and while the price per MB is still quite high... it exists in volume and isn't vaporware, which memristors by and large still are.

A 3' USB 2 cable costs $2.02 at Digi-Key (stock# Q361-ND), qty 1. With USPS shipping it'll still be less than $10 total ;)

If you're buying something that's a generic electronic component/assembly, you don't go to a computer store, you go to an electronics distributor.

How about not using tantalum?

http://www.digikey.com/us/en/ph/Panasonic/tantalum.html

I suppose Apple's R&D team might not have been up to the task of finding alternatives to tantalum, but with all the billions of dollars Apple has at their disposal (and all the profit they made on iProducts, which were all made using conflict minerals) they could have set up some research teams and labs. Assuming that they actually cared about the issue, which I would not be so quick to assume (to be fair, Apple's investors and customers never cared, they just wanted to see profits and have sleek looking toys).

As for Steve Jobs' statement, why not apply it to working conditions as well? After all, Apple must have its factories in other countries, just like they must use conflict metals, so how are they supposed to ensure that the factories are not mistreating workers? Dell does it too, right?

the same way self winding watches work. Your arm is not a windmill either. In this case, a small magnet, in a tube, wrapped in a coil, such that when the user walks, the magnet slides from one end of the tube to the other, and back again. The real trick is to figure out how to arrange this little setup to maximize the number of times the process occurs, with minimal movement.

No.

Watches will run years on a CR-2025 battery pumping out 163mA @ 3V =~ 0.5 watt.

Smartphones barely last a day with a 1300mAh @ 3.7v = 4.8 watt battery

Using a self-winding mechanism similar to a watch in a smartphone would be completely worthless, it wouldn't power the phone for more than a few seconds

That's what I meant by "busbars for power distribution" :) You can of course use 48V coils to get lowest current at a safe voltage, but the dissipation will remain. And 48V small form factor relays aren't cheap. You could cheat and use optomos SSRs, but that's really aiming low ;)

It could be possible, perhaps, to have the "latching" part done a-la core memory: store charge in a "cell" made up of a capacitor storing enough charge to energize the coil momentarily -- long enough to latch a relay electrically (NO contact powering the coil). Let's see if it's feasible.

Say we use TYCO's TSC series relay. 6mA @ 24V for the coil, 5ms to operate so say we need it to stay, say, on for 20ms on capacitor charge alone. Final discharge voltage could be as low as 18V per the specs. We're discharging the cap through a 4kOhm resistor (24V/6mA). So a 30uF capacitor is plenty enough if we're starting from 24V, it'd be still around 20V after 20ms. I've used this handy tool. To keep refresh rates low, you could use a much larger capacitor.

So -- I'd say that a fairly small capacitor may be all that's needed to implement memory. You'd have row/column relays to connect the cap to the coil of the sense relay, and then that relay would latch itself electrically. They did have electrolytic caps with those specs back then (tens of of uF at 35V V.W.). The reads aren't even destructive -- the sense relay latches when the coil gets a kick from the stored charge, this energizes its coil from 24V using a N.O. contact that just closed. This also recharges the capacitor if there's no isolation diode between the capacitor and the coil. As soon as the row/column relays disconnect the capacitor is out of the circuit, fully re-charged.

If you had a full column of sense relays per each plane of memory, then refresh could be very fast as well. The circuitry for refresh (apart from refresh counter etc) is simple: one isolation relay per row, one sense relay per row, that's it. Nothing else is needed. The isolation relays close connecting the row outputs to sense relays, sense relays maintain the state of their capacitor and recharge it. If you wish, you could use the column of sense relays as the readout relays as well, then the isolation relays would be on the outside of the memory plane rather than on the inside -- they'd be connecting the memory to whatever bus it feeds.

You need one capacitor per bit, so 16 kbits worth of "RAM" would cost you approx. $500 for the capacitors (assuming you'd use through hole ESH476M035AE3AA from Kemet, those go for $0.03249 US each at 16k quantity from DigiKey). If you'd want it to be a 16 bit memory, then you have 16 planes of 1kbit each, organized 32x32 bits. Column select relays can be shared between planes, so you need 32 relays for that. Each plane needs 32 row sense relays for refresh and readout, and 32 row select relays for the output. So you need 32+32+2 relays per plane, or 16*66=1056 relays. That reduces your relay cost by a factor of 16, and reduces your power consumption even further since at most about half of these relays would be on at any given time -- you only select one row at a time for output. You'd also need some relays for the refresh counter. You could of course have 8 planes of 32x64 bits for an 8 bit memory, and then you'd need 576 relays (64 per plane for rows + 8 per plane for shared column selects).

The relays go for about $1.176 in 1000+, again from DigiKey. I'm sure you could optimize the relay count further, perhaps by using diode switches. You'd need to use some diodes anyway, for things like decoding row/column selects from the address bus and from the refresh counter, etc. If you'd hook up rows to the least significant address bits you could probably forgo a refresh counter and just assume that enough straight-line code gets executed that all rows will

The PCMCIA/CardBus connector alone will cost you $9.29 + shipping from Digikey. However you can't just "wire it up" because its pins are too small and fragile. So you need to make a PCB for it, that can't be much more than $100 or $120. Of course once you put the rest of the breakout connectors onto that PCB it becomes around $150. At this point it becomes cheaper to buy a small netbook or a small Atom-based motherboard.

This whole idea seems to be tailored for people who want to build a computer. However majority of people, by my observations, are far past that. Today I don't want to build a computer. I want to build a thing that uses a computer as its part.

For example, right now I need a computer that has a USB host interface to talk to my weather station. The weather station console plugs into a PC and runs very nicely; but I don't have a PC near the console, and I don't want to run a big, noisy and hot PC just for that. I want something under a couple of watts that generates network data. I'm willing to build something but I don't see much sense in building a PCB. If I do that I will then build my own network-ready system out of an AVR32.

re-use of *existing* connectors, housings and assemblies keeps the price right down

lkcl, before you jump into production please make sure that you don't want your SATA and USB work. Because they aren't very likely to; the PCMCIA connector is not a controlled impedance part, and your pinout requires 90 Ohm differential for USB and 100 Ohm differential for SATA. Ethernet is also 100 Ohm, but it has plenty of margin. Even if the board works on the bench, it's not the right thing to do. You need a proper differential connector, something that you can get from Samtec, for example.

I really don't know how much you are an expert in manufacturing, but I built a number of professional designs, and I strongly suggest that you don't pick an old, obsolete connector just because you think it is cool. You need to consider the other side of the connector. How many PCMCIA cages can you find at Digikey? How many of them are easy to solder by hand? Hell, this connector would give *me* trouble, and I can solder 0402 all day long under the microscope. This connector has pin spacing of 0.635 mm, and practically none of your customers can solder it.

I still don't quite understand the business idea of your product. By "business" I don't mean making money; I mean "delivering value," making good things. What value do you expect to deliver if nobody can connect to your board? Your super-small form factor is a problem here. Very few electronic enthusiasts are so much concerned about size and space. They are far more concerned about being able to see the parts without using an electron microscope. If you'd ask me, I'd say you need to think how your customers are going to use your product.

The talk about standard connectors ... if you want it done right, use COM Express. These modules are interchangeable and your product would actually fit into an existing market. You can actually sell the thing without Slashdot. Inventing your own standard, using an obsolete connector and breaking the electrical signaling requirements will not do you any good. You are not large enough to establish a competing standard, and your design is not as good anyway. But if you don't want to deal with COM Express (which is not a pleasure to solder either, I admit) then just forget the unification and use plain vanilla 0.1" headers for everything except high speed interfaces. Or include a CardBus breakout board with your CPU board.

If one is in a hacky sort of mood I would suggest
A Beagle Bone http://beagleboard.org/bone
and then add this http://redpinesignals.com/Products/Chipsets/RS9116.html
and maybe this http://search.digikey.com/us/en/products/ENC424J600T-I%2FPT/ENC424J600T-I%2FPT-ND/2126005
It is only 100Base-t but it would probably be good enough for the connection to your broadband.
Linux plus less power use. Of course a LOT more work.

Forget the EEPROM. The concept of programming a ROM seperately from a chip is so 1970's.

Get a programmer that programs chips with on-chip flash.

I'm biased in favor of Atmel's AVR architecture. http://www.avrbeginners.net/ http://www.avrfreaks.net./

You need to decide: will you go with dated (but doable) through-hole technology, or will you go surface mount (SMT) which is more modern, but more difficult to solder. That will impact what kind of programmer you need. Atmel AVRs can be programmed in-curcuit with a cheap dongle.

I don't always design in-circuit programming, debugging, and emulation into my circuits, so I keep a few of Atmel's AVR boards around. The STK500 is awesome: http://www.atmel.com/dyn/products/tools_card.asp?tool_id=2735

$82.16 at Digikey: http://search.digikey.com/us/en/cat/programmers-development-systems/general-embedded-dev-boards-and-kits-mcu-dsp-fpga-cpld/2621773?k=stk500

You can get samples of the AVR Microcontrollers from Atmel's distributors, or they are available at many resellers, including DigiKey. Search for "atmega" and limt yourself to DIP packages.

(Just as a side note: the electronics hobbyist community has gotten used to dealing with surface-mount parts.)

Also check out:

Adafruit: https://www.adafruit.com/ (Sells arduino and other microcontrollers, as well as "heathkit-like" solder-it-yourself electronics kits).

Dangerous Prototypes: http://dangerousprototypes.com/ (Among other things, they were involved with designing a naked-board, 16-channel w/12K sample depth, 100 megasample/sec digital logic analyzer -- for US$50. Then some guy took the firmware and added as many features that he could based upon an HP 16550a timing logic analyzer.)

Seeedstudio: http://www.seeedstudio.com/ (they're a store that sells cool hardware for arduino and others -- I think they're in China, though)

Digikey for all sorts of electronic parts: http://www.digikey.com/

Jameco Electronics for parts and electronic kits: http://www.jameco.com/

Digikey has 17,000 in stock axial resistors. HSC Electronic Supply probably has some as well, but their website isn't responding. (One of the few things I miss from the Bay Area is HSC.)

Wow, that sounds awesome! I guess the only drawback would be the whole non-existence thing.

OK, they don't exist in the same way a single charger standard doesn't exist. But they do exist. In fact, you can buy a UC right now: There are 522 different models available at DigiKey.

The slow, painful death of Radio Shack is more than symbolic. I see it as completely parallel to the slow and painful death of intellectualism in our national culture.

Or, you know, that Internet thing: http://www.digikey.com/ http://www.newark.com/ http://www.mouser.com/

This sounds like it is practically lego like. If you get light, motion, temperature, humidity, pressure, gps, accerometers, gyros, magnetometers and motor/gyro controllers for this thing, you'll hit almost the entire robotics, weather station hobbyist market. That's a fairly substantial market and would make it worthwhile.

However, I'm an arduino hobbyist primarily because I can open a catalog from some place like digikey and be able to write code to interface with just about anything in there.

Yeah, if you aren't a hardware guy, you might want someone to have already figured out what capacitors, resistors, transistors, diodes you might need to interface with a sensor or whatnot and what the specs of those components should be. The prepackaged modules fit the bill for that is much the same way as an arduino shield.

If you aren't a low level software guy you might be a bit overwhelmed when reading specs full of timing information and not want to deal with it. But there's definitely a place for a simple low-level microcontroller platform that actually lets you get to the bare metal and this .NET Gadgeteer isn't it.

I share your disinclination to get too excited about any widget that has only been made in an academic lab, but super-capacitors aren't theoretical or non-commercial. Look, you can buy 'em on Digikey: http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=131084&k=supercapacitor. Now the magic nano-particle ink on the other hand... (I believe they can make it, but cost effectively?).

When the power failed and they used the battery backup they all kept crap time, often being out by a minute per hour.

The error then would be about 1.5%. My guess is that your clock switches to an RC oscillator, and the frequency is then determined by tolerances of components. No crystal could be that bad.

Also another poster above mentioned that some clocks have an internal switch for 50 or 60 Hz.

One such switch costs more than a few crystals. Besides, it's another "maintenance" item that could be incorrectly set by the customer. I guess some clocks were made this way, after all, but I'm not guilty of that :-)

A simple crystal is cheap. A good calibrated crystal with temperature correction and such is not so cheap.

You most certainly don't need a TCXO. If you get one, like DS32KHZS#T&R, it gives you ±7.5ppm. This translates into 4 minutes of error per year if the frequency error is never adjusted or otherwise compensated for. There are temperature compensated crystals with better stability. However a common crystal comes with tolerance ±20ppm and hopefully has stability that is not worse. This figure translates into about 10 minutes per year, and that is perfectly fine for most people.

If, however, you can't accept the fact that you need to touch your clock at all, you have an option of using WWVB broadcasts at 60 kHz, or WWV that is broadcast on HF. Or you can get some Rubidium or Cesium standard.

When the power failed and they used the battery backup they all kept crap time, often being out by a minute per hour.

The error then would be about 1.5%. My guess is that your clock switches to an RC oscillator, and the frequency is then determined by tolerances of components. No crystal could be that bad.

Also another poster above mentioned that some clocks have an internal switch for 50 or 60 Hz.

One such switch costs more than a few crystals. Besides, it's another "maintenance" item that could be incorrectly set by the customer. I guess some clocks were made this way, after all, but I'm not guilty of that :-)

A simple crystal is cheap. A good calibrated crystal with temperature correction and such is not so cheap.

You most certainly don't need a TCXO. If you get one, like DS32KHZS#T&R, it gives you ±7.5ppm. This translates into 4 minutes of error per year if the frequency error is never adjusted or otherwise compensated for. There are temperature compensated crystals with better stability. However a common crystal comes with tolerance ±20ppm and hopefully has stability that is not worse. This figure translates into about 10 minutes per year, and that is perfectly fine for most people.

If, however, you can't accept the fact that you need to touch your clock at all, you have an option of using WWVB broadcasts at 60 kHz, or WWV that is broadcast on HF. Or you can get some Rubidium or Cesium standard.

This one is within 2.5 minutes per year.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=300-8763-ND

These can be calibrated via microcontroller and high precision clock for much better accuracy, but no one would do this for a cheap clock.

Now, there's no choice but to go to DigiKey and Mouser, and figure out how I'm going to meet their minimum order requirements, when all I wanted was $5 worth of stuff

Um... what's DigiKey's minimum order again? I regularly buy small quantities of stuff from them. AFAIK, they have no minimum order. And they're fast and reliable.

(Posting as AC because I'm too lazy to login) Maybe they've dropped it; but I thought it used to be $25. I guess they DID drop it!, summabitch! THANKS!!! Shows how long I've been ordering from DigiKey, LOL!

http://onlinecatalog.digikey.com/skin/entrymap/entrymap_DigiKey.asp?SkinId=7.4.2.7

That's somewhat variable.
Peltiers basically blow if you use them at over half their 'sticker' maximum temperature difference.
At that point, they have perhaps a COP of 1.
At a temperature difference of around 1/6 maximum - they are up to around a COP of 4-5, which
isn't bad at all.
However - this is a delta of 6C or so - which isn't really usable in most applications.
It's worth noting that a COP of 1 isn't useless.
If you can make it cheap enough, you can make a electric heater with double the output.

I should have actually saved the graph I made.
To replicate - go to http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=102-1663-ND get the datasheet - now refactor the graph into power in vs heat pump capacity over temperature and current.

Like Japan, Taiwan does a lot of high-tech manufacturing.

There is more than one level of high-tech manufacturing. It's one thing to take a 0402 capacitor and put it onto the PCB. It's a very different thing to make that capacitor from microscopic parts in the first place. Do you think there are no trade secrets in ceramics that allow you to cram a few uF into an 0402 part? (Murata is a Japanese company.) Even this tiny segment of passives is dominated by US and Japanese manufacturers (TDK, Taiyo Yuden, Kemet, Panasonic, Murata.) Even AVX, a very solid US manufacturer, has nothing to offer if you need 4.7uF in size 0402.

Companies like Panasonic-ECG and Rohm are doing very well, and they are producing very cost-competitive components. If you are looking for a low cost surface mounted aluminum capacitor, Panasonic is the most likely manufacturer.

At about a buck a good quality silicon version is already great for hackers and hobbyists.

I just did a survey looking for some lab hardware, and their stuff really isn't that competitive with TI. (And I'm not going to even get into the thermal engineering / power supply issues that have popped up on some forums)

F.ex., you can get a dual-core, A9-based board with similar features for $175.
http://www.digikey.com/us/en/ph/texas-instruments/pandaboard.html

Admittedly, it doesn't have "a plug" (or a case for that matter), but are those things really worth that much? If you're coding on one of these... you're probably not Joe Sixpack taking a break from the Superbowl.

(Would love to hear dissenting opinions and/or link! I'm not trying to shill TI's stuff here, but it does seem there's a lot of price disparity in the embedded protoboard / SBC market. And that's not even getting into all the companies still selling previous generation hardware for full price...)

The large squarish chip in the middle is an atmega 8535 microcontroller. The two rectangular chips farthest from the USB connector (shiny metal thing) drive the LED's (MIC5400YWM). Brightness of each of the 8 LEDs' 3 colors (24 total) is controlled by a 10-bit PWM, at 1.3KHz. Each color, collectively, can have its current adjusted, using a 4-bit DAC. Each LED can be set to off; on, at some brightness and color; blinking between the "on" state and "off" state; or phasing in and out (like a constantly turning dimmer switch).

But, if you just wanted on/off for each of the 24 LED's, all you would need is a smallish USB microcontroller, an I/O expander (because 480mA is too much for one MCU), and LED's

Project Website, including pictures
MIC5400

Please, nobody mod me up! We've gotten far off topic, and I really don't want my site to get slashdotted - it's being hosted in my parents basement, from an OpenWRT router.

Well, I may an idiot, but I think you've jumped to that conclusion prematurely. I have done quite a bit of research in this area trying to find some prior art, things got close a few times, but no cigar.

As to your claim that it's possible to do this with an existing FPGA, According to Digikey, their "biggest" Xilinx Spartan 6 FPGA, which prices out at about $150 is capable of providing 5831 CLBs... which is less than 1% of the capability of the bitgrid chip I proposed above.

A chip devoid of specialized routing hardware and all the complexity that entails, will be far cheaper to design, test, and ship out the door. I estimate, base on NO actual experience, just a gut hunch... that $10.00 for the final device would give a very nice profit margin to the manufacturer. I would imagine that a second generation device would include far more cells, and perhaps some specialized I/O.

The FPGA industry optimized on complexity, and trying to get the maximum performance out of a piece of silicon. It's my thesis that they prematurely optimized, and a much simpler architecture could provide a new class of solutions which may be far more efficient for a number of applications

As you said, building the FPGA isn't the hard part... actually understanding the architecture enough to maximize its use is. The BitGrid is dead simple, can process data in all 4 directions simultaneously, can route around defects, and can add/remove a bit of precision from a function with no major hassles. This is NOT the case with an FPGA design.

The thing I really need to find out, is just how much power does a 4 input/ 4 output LUT actually consume. I haven't been able to find that type of information, as it's all behind paywalls.

In any case, thanks for the time and attention and discussion.

There may be weird command paths that produce unique delays and unless you tested all possible combinations of commands so you can emulate everything, you can't be sure there isn't something left.

That would be indeed a somewhat worthy challenge; though the hacker would just run the tool for a day or two and collect all feasible code paths and delays associated with them. That alone wouldn't be a big deal to spoof.

However in practice a dependency on those "unique delays" is impossible. The average life of an IC on the market is anywhere from 6 months to 1 year. This applies to everything, from external USB Flash (storage and the controller) to internal (parallel or serial) Flash to, as matter of fact, anything else. Nobody is willing to produce obsolete devices, and there is no need to either - they do a decent production run, pay some big bucks for that, and sell the parts until they are all gone. Then a new part is sent to manufacturing.

Replacement ICs, even though they are [sometimes] functionally identical, will have any number of differences in those "unique delays." So if you originally used some TSQ1234ZS and it's now obsolete, you solder a new TSQ1235ZSG and it's all of a sudden incompatible. This makes an OEM's life very interesting, to put it mildly, even if you just use the part per the datasheet. But if you went insane and decided to bet everything on undocumented features ... did I mention "insane" already? :-)

And as a side note, typical delays in ICs are pretty small, they are measured in nanoseconds usually. The Flash erase or write cycle is longer, but you can't write just to authenticate. Reading from Flash is pretty fast, around 50 ns if not faster. You need a very accurate clock to measure possible differences between accessing of certain addresses ... and that is possible only if an async device is used (one that tells you when it's done.) Synchronous devices do not tell you anything, they just return the data a bit faster than you are reading. In theory it's possible to probe individual addresses at different speeds and find the delay that is the threshold of data delivery. But that would require a complicated controller, with a DCM probably, or with a clock that is around 1 GHz.

It's far more practical to use instead a chip that is designed for auth/TPM use. That would be a secure (tamper-proof) microcontroller with a key that is programmed (once) and with some algorithms to generate whatever signatures or encryption you desire. That microcontroller would be in fact reviewed by a competent person to see if it leaks key material through its power pins or RF - and that won't happen with any Flash. And try to beat their 3-pin SOT23 size.

It's news to people young enough to be surprised.

You can still buy Intel 386, though Wiki states production stopped in 2007. Other fabs are still going.

I'll submit next week's ancient technology shocker now: NASA still uses interchangeable threaded fasteners.

I don't mean a flat on the mating part of the connector, I mean a flat on the plastic body.

http://media.digikey.com/photos/Assmann%20Photos/AK%20678-2.jpg

Modern receivers are small, cheap and low power to integrate.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=TEA5767HN/V3,118-ND - for example is a FM radio chip.

It comes in a 6*6mm package, with under 5 tiny cheap external components required, simply adds onto the I2C bus present in most all phones, and the total price at 100K is around $1.2.
The operating current is at 10mA typically a small fraction of the power needed to decode mp3, and when unused it draws essentially no power.

In newer chipsets, it tends to come along for free, as it's integrated into many bluetooth chipsets these days.

A little good news -- the cost of a ghetto-fabulous JTAG programmer has come down. WAY down. FTDI released a single-chip USB host a few months ago with onboard JTAG capabilities AND ready to use royalty-free driver DLL for Windows. It's around $12 for the bare chip, and around $28 for a breakout board with the chip and support components soldered to it ( http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=768-1030-ND )

It still sucks to have to even screw with JTAG for this, but it's not *completely* hopeless.

Now, what would be REALLY funny is if someone motivated by desire to root & reflash his DroidX ends up using his new knowledge and JTAG to crack something whose security really DOES matter to Motorola, like his cable box. The Law of Unintended Consequences has an amusing way of extracting periodic revenge ;-)

> Oh, so we just have to wait a couple of weeks for some teenager to crack it. Awesome.

If it's hardware-based 2048-bit encryption, it's not going to be hacked in a couple of weeks. CSS encryption used on DVDs was a complete joke of an encryption standard, and everyone knew it at the time. It was security by obscurity, and almost worked for a couple of years.

When it comes to military-grade hardware encryption, Motorola doesn't screw around.

If Motorola doesn't back down, realistically the best prospect for reflashing a DroidX is a homebrew JTAG programmer built with a FTDI 2232H on a breakout board -- http://ftdichip.com/Products/FT2232H.htm

About $30 worth of parts (plus shipping) from Digikey -- http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=768-1030-ND

God, talk about the Law of Unintended Consequences -- savor the irony if Motorola becomes the company that makes JTAG a household word :D

No shields, which is why it's rather pointless. He just used the SPI interface pins connected to one of these. He even had to perform voltage level conversion.

To answer your question, you can just get any bitbanging USB JTAG interface based on the FT2232D or FT2232H chip. I own this one, which also happens to include a USB to RS232 converter channel (since the FT2232 has two comm channels). FT2232D versions are more common but are only USB full-speed. FT2232H versions can bitbang faster, as they USB High-Speed peripherals. You can use these with OpenOCD, which should work on Windows and Linux (and OSX and other OSes).

They sell to anyone, or you can buy their modules from Digikey.com, etc.

The cool thing about the modules I use is that they're intended to be rs-232 modem replacements. As such, they act as a transparent comm channel by default, but can also be put into an API mode where you can send explicit commands and data to any node(s) simultaneously.

The other cool thing is that they have on-board A/D converters and digital I/O lines that can be sampled explicitly _or_ the whole module can sleep for a specified period, wake up, check for data, take some samples, send them, and go back to sleep. This is excellent for remote battery-powered endpoints.

Take a look at the product manual for their XBee ZB OEM modules. If you're interested in playing around w/ ZigBee, their starter kits can't be beat - they include several different modules, prototype boards, ac adapters, cables, etc. Everything you'll need to get started.

Be careful of their product names - they have a ton of products with very similar names. For ZigBee you want XBee ZB or XBee-Pro ZB, NOT XBee Znet 2.5 or digimesh or 802.15.14 or anything else. The -Pro means high power, btw. 100mW vs 1mW.

The Znet 2.5 modules are the same hardware as the ZB ones, the only difference is a firmware flash.

Support page for XBee OEM modules

Their store

One of their starter kits

starter kit at digikey.com - only $129.

Just another stupid me-too handheld. Why doesn't somebody start putting BeagleBoards into a case with a 480x640 touchscreen LCD??? That, I would buy.

A few op-amps. One configured as a sawtooth generator. The second as a comparator.

It would cost more. The reason is that you need at least one RC pair to set the frequency, and you need a few more resistors to set the gain for those OAs, and the variable threshold for the comparator. And still an OA as a comparator is not an ideal solution, with gain set too high it may become unstable, or its bandwidth may drop below your intended switching rate. A good comparator here should have a hysteresis, and you can get such a comparator at Digikey for something like $0.64.

In any case, this is all doable, of course, but it can't beat a microcontroller in a SOIC8 package (ATTiny) where you just apply power, connect your LED to the PWM output, and connect your control to some other pin... A microcontroller today is cheaper than just one tantalum capacitor. And it allows you to create any input/output dependency, not just what your OAs are set to do. The pure hardware design won't let you build a pulsing light, for example - but an MCU design can do that and more. From a hobbyist POV the MCU is the way to go. Doing it in hardware makes sense only when you are dealing with specific requirements that aren't achievable by the MCU; latency comes to mind as an example - a popular "do or die" requirement in ALC circuits.

There is a reason soldering iron handles are bright yellow.

I haven't seen a professional soldering iron with a yellow handle. Usually they are black or sometimes cyan as it is a trademark Weller color. Hakko was traditionally black but now has blue irons too.

All these irons are pretty safe - in part because they come with enclosed stands, and in part because the handle's shape allows you to feel the position of your grip without looking. After a few years of practice burns of that type just don't happen.

The most popular type of a light burn among novices is produced by holding the part with fingers and soldering it.

There is a reason soldering iron handles are bright yellow.

I haven't seen a professional soldering iron with a yellow handle. Usually they are black or sometimes cyan as it is a trademark Weller color. Hakko was traditionally black but now has blue irons too.

All these irons are pretty safe - in part because they come with enclosed stands, and in part because the handle's shape allows you to feel the position of your grip without looking. After a few years of practice burns of that type just don't happen.

The most popular type of a light burn among novices is produced by holding the part with fingers and soldering it.

What an early adaptor might look like:
http://rocky.digikey.com/weblib/Altera/Web%20photos/PL-BYTEBLASTER2.jpg

But, but... the ATmega644P costs 9.28$USD!

And you can keep your half-sunflower seed ATtiny10, I'd rather use a DIP-8 ATtiny85!

And your ATtiny10 is actually 1.19$USD, so don't crap on my 2.44$USD ATtiny85. ;)

* This message was not approved nor endorsed by Digi-Key.

But, but... the ATmega644P costs 9.28$USD!

And you can keep your half-sunflower seed ATtiny10, I'd rather use a DIP-8 ATtiny85!

And your ATtiny10 is actually 1.19$USD, so don't crap on my 2.44$USD ATtiny85. ;)

* This message was not approved nor endorsed by Digi-Key.