The mythical $5 microcontroller

I think us hobbyists are just plain cheap.

I've never had any of my customers come back to me and say my boards are not worth the price. In fact, mostly the opposite. There are over 50 parts on my MAVRIC-IIB board. I sell lots of boards to companies making and prototyping products and solutions, and I'm sure you do as well. These are folks where time matters a lot - they know that the lost time spent breadboarding and testing the equivalent of my MAVRIB-IIB would cost them many many times the price of buying them from me already designed, debugged, built, tested, ready to drop into their target application. So the price is really a no brainer.

But us electronics/robotics hobbyists - and I'm guilty of this too, we like building stuff. Most of us have a DIY mindset. I tend to build my own h-bridges even though commercial ones are available. I'm just that way. But if my company was paying me to "make something move," I would not waste my company's time and money by building my own bridge

- I'd purchase a proven design. If it's my own project and time is not of the essence, I'll prefer to build my own, probably better than most commercial products I've seen and with the exact features I want. I do enjoy designing and building many of the parts I use on my robots.

When it comes to radio modules - no way, it's out of my field of expertise. I like the MAXStream 9XStream transceiver modules available from Digikey for $42 each and I'm happy to pay it.

While you might not be able to build your mythical board for $5, you can get close or for a little more. I would typically use a small breadboard, ATmega8 or perhaps an ATmega32 DIP, MAX232 + 4 or 5 caps. Program it using ISP using simple cable programmer to the PC parallel port + a few resistors. I perfer GNU GCC for high level C program development which is freely available - not because it is free though that is nice, but because it is superb and works extremely well on my development environment of choice - Unix.

It _can_ be done very much on the cheap, the above parts are really all that is required. Probably around $10, even counting the breadboard to hold it. But it is _not_ a polished solution.

They exist - they're just not as polished as an end product. I consider these as being similar to MLW's hacked mouse encoder. It will just never touch a well designed built-to-purpose encoder made to fit the motor.

As just a small example, I mentioned there are over 50 parts on my MAVRIC-IIB. Some of the more expensive parts actually go into something as "mundane" as the power supply section; I'm a sticker for good stable power supply with proper bypassing and the regulator is superb. Pricewise it is many times the cost of a typical 7805. But I don't want my customers' boards to die when they accidentally apply power backwards (the regulator protects against that) and I absolutely don't want to be chasing down phantom problems due to poor power layout. Good power layout is generally something that you can't really even do on a breadboard due to the layout constraints. So a hand-made $5 or $10 circuit on a breadboard won't even come close by comparison.

-Brian

-- Brian Dean BDMICRO - ATmega128 Based MAVRIC Controllers

While not a very high end microcontroller, I have a whole box of picaxe

08's. They dont make them anymore, they've upgraded to the 08M's which are mroe powerful. They're only an 8 pin micro, and cant take alot of code because they're Basic based systems (on-chip interpreter) on a flash PIC.

While not as powerful as alot of things I find them invaluable, and can get them here (in america) through peter anderson for ~3.00 a piece (actually 3 for $10)

They're only 8 pins, only run at 4mhz, are interpreted so it's even slower, but it's a single chip, programable via 2 resistors, has 5 I/O's, and room for enough code to make an amazing number of chips for menial uses. Revolution Education (makers of the picaxe) also make bigger chips, up to 40 pin, but I almost always go for the 8 pin version when I need something done quick and simply. I also use other pics, and have recently moved to AVR's (AVRMEGA32 so far to be specific), but being able to program them in basic takes only a minute, and programmed through two resistors rather than a programmer takes jsut a few seconds. It's almost like having your own ASIC factory in jsut 5 mintues of work.

The holy grail of $5 micro's? No. Most of them are $15 and up unless bought in serious bulk. But Ii've used these little picaxes to get around ALOT of problems very cheaply and very quickly.

--Andy P

Actually, Randy...

Rather than guessing at what people are building, there are a number of sites that contain example robots and describe what's in them, and some builders mention their cost. The DPRG, which you belong to, has a robot gallery, but a very good one worth browsing is Robots.net, which I'm sure you're also familiar with, as it's run by current and past DPRG people.

I like to go to the index page and just thumb through the robots. Knowing what people build really helps in knowing what they want to build -- and therefore what they might buy. (Yes, there are a couple in there with PICs and AVRs, along with some that have just one transistor. That's the nature of hobby robotics.)

Yes of course this $5 microcontroller may require some other investment to program, but that investment is made once. You wouldn't expect your car mechanic to go out and buy a new set of socket wrenches for each car he serviced, right? People don't add in the cost of a volt-ohm meter or oscilloscope or soldering iron to the pricetag of their robot. These are tools of the trade that, once used, can be used again.

As for your AVR-based board not selling, what were you attempting to sell? AVR development boards are a dime a dozen now, precisely because of the popularity of the chip, and there are already some "leaders" in that field. I don't think Parallax would have sold a 10th of their BASIC Stamps had they not also provided thorough documentation, tons of app notes, school curriculum, published books, magazine articles...you get the idea. A $50 BASIC Stamp is a $5 microcontroller with $45 of support behind it. That's how you have to look at it.

-- Gordon

Gordon McComb wrote: [...]

Exactly! The point I tried to make with mlw as regards OS and computer languages. You need more than a good product you need to sell it by showing the buyer it will get them what they want, not what you think they should have.

-- John

Geez, Gordon, this is getting worse by the minute. I thought your $5 micro was stretching it. Now, one post later, they're $0.00833 for a full development board? No wonder I can't keep up.

Maybe that is an Ebay dime a dozen. Twelve boards for $.10, shipping and handling is $100 per item . ;-)

Certainly! In cars, micros are cheaper than wire. Look, I'm not talking about volume processes. You really can get a useful micro for $.70 (even in volume 1 ea). But that is a real micro chip, A chip, not a solution. Certainly not the mytical $5 micro that is so often listed as the solution to all our control needs.

That $.70 chip is known not to be the system cost. Is there a crystal? Oh, no, another $.50. Is there a regulator? Oh yeah, well, I'm not going to count that because I've already got 5V over... oh, it's not beefy enough, I'll just order a heftier part, no problem.

The phantom $5 micro comes with all these included for free, doesn't it?

Now the mythical $5 micro is supposed to cost $5 and be the solution, the answer, the unarguable indesputed rock solid pre-existant system. Instead it is a phantom, as turns out, nobody has ever seen or realized (in low volume).

Yes, this is a very good example. You could just as well say, "It's just a simple matter of using a $5 micro" as to say, or at least to follow up with, "problem can be easily solved because a program can be written to do it". Rrrrrrrrrrrrright. Just those minor details, and we're finished.

Randy,

Wow, that's almost a rant! We are getting to see a whole new side of you :-)

I suppose you are right though. I know that I am responsible (if not in voice then in action) for being just as you state. I tend to look at something and think "I can do that and I can do it better!" If only I did not have to spend so much time earning a living then I would be able to make a few more of those claims come true (or maybe not, but better to try and fail than never to try at all). Even when I do take some idea and run with it, starting with a $5 PIC, AVR, or whatever, by the time I am done I certainly have a lot more than $5 in the project. Still, in the robotics hobbyist community, we are specifically a group of people who in general are exactly what you calim we are: We see something and think we can do it better and cheaper. We are dreamers who refuse to squelch our dreams just because the reality of life (limited time and budget) keeps holding us back. At the end of the day I would rather spend $100 and 100 hours working on something that I made myself than buy someone else's kit and just glue it together. I think that the hobbyist community will always be that way. We are more interested in creating things ourselves, and working out the problems ourselves and gaining a deeper understanding of the problems and solutions than we get by buying canned parts. It's simply way more exciting to have your robot fail and have the h-bridge burst into flames than to just buy one from IFI that can handle any motor you throw at without breaking a sweat. The feeling of accomplishment is so much deeper when you have built it yourself and it actually works. When I hear some youth Thunping down the streen with a million watts of stereo in his car and I see that look on his face of "I'm so cool because my stereo is better than yours", I always think "yeah, you have more watts, but anyone who wants can just go to the same stereo shop and spend a little mor money and get more watts than you. If you want to impress me, show me what YOU can do." Robotics is the same way. When I go to a competition and a winner opens up their bot and I see a bunch of canned gear from known and reputable vendors, I think "nice kit, my 10 year old could have built that kit too and probably taken the prize." I'm much more impressed with the guy who lost because his h-bridge fried or his PID loop went nuts when the 16 bit wheel encoder counter he used for odometry rolled over.

I, like most hobbyists, have a load of bits and pieces that I have bought over the years. Some because they just can't be beat and some just to see how they work. For example I have one of your (new micros) ServoPods. What a cool little board. While I'm not the biggest fan of FORTH in general, I love the state machines and the "command line interface" give it such a multithread OS feel. I just love it. However, I will admit that I have only 1. I use it to try out new things (like it's the first thing I attached the theraminvision to when I got it assembled). I even developed a few I2C devices for a client and I used it to do the initial development of the command set for the new slave devices. But at $200 each, that same old thing pops up in my head again: "I can do it better, faster, cheaper...", and while that is actually not true, it turns out that the ServoPod is way overkill for most of the applications I initially use it for, so by the time I design something to replace it, the replacement is generally cheaper and works as well as (or better than) the ServoPod because it's designed specifically for the task (and never mind that when I buy from someone else, they actually do like to make a little profit).

All of that said, that is my hobbyist approach. When I'm doing work for hire, I just want things that work and that I can hit the ground with quickly. Usually in the professional sense, time to market and reliability are more important than unit price. I have actually delivered a few black boxes to clients that had a 'Pod inside. But it sure wasn't a $5 part!

I guess where I'm going with all of this is that in the professional market, a $5 microcontroller does not matter because engineering costs are spread out over production quantities, and in the hobbyist market even if there ware a $5 microcontroller we would still say "I can do that better, faster, cheaper...". I have quietly read many of your posts about your new motor controller and it's many features and small size. None of them have mentioned a price point, but in my head I keep thinking "I can do that...". However, when a project for hire comes along that needs something like that NOW and that's proven to WORK and my own "better, faster, cheaper" unit is not ready, you can bet that the first place I'll go is the new micros web site and click the buy button. I'll build what my customer wants and deliver it with confidence that it's going to do what it's supposed to do. Then after I get my check, if there is anything left over after I pay my bills, I'll probably continue to work on my own "better, faster, and cheaper" one. That's just my hobbyist mentality. I'll never let the dream die...

-TE

Exactly! Now you're getting to the essence of it. The micro is cheap.

?Ref=377168&Row=236377&Site=US It turns out though, it's actually $15.05 from DigiKey.

Huh, imagine that? It ships for $15.05 but somehow only costs $5 on the other guys board. Must be the new math. Oh well, this one is a little better, and I might need the programming space.

Oh, come to think of it, isn't the shipping of the chip from DigiKey more than $5? Opps, it isn't a through hole device, gotta make a board. Can you get a single PCB made to hold it for $5? Or can you make a board by hand for less than $5 of chemicals and broken drill bits? No, huh? Isn't the shipping of the $2.50/sq.in.PCB more than that, too? Huh! It's in now, +/-$40 some bucks later, and it still isn't working. Well, it's just the matter of a simple program now. Any average robot maker should have that knocked right out, in about two hours, and three weeks of hard debugging and head scratching. And hey, don't forget those fuse settings...

The Mythical $5 Micro!

A myth of vast proportions, and myth of lost dreams.

The Mythical $5 Micro, piloting many abandoned, silent, and motionless robots. What a savings!

The $5 Micro could be made to work with seperate radio transceivers on each port thus making it a self-contained unit. Any additional components or peripherals are then in a seperate category from its deemed description. Add-ons are seperate, affordable commodities. What should be the transceiver range?

----------------------------------------------------------------------- Ashley Clarke

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As if the concept weren't hazardous enough?!?!

Oh, as long as we're just discussing mythical, why not spec the range for just a little over half way around the Earth? Enough you could get a good overlapping from low orbit. Not that we'd have to go far, like, the moon or anything difficult like that. And all conditioned that it doesn't raise the price much over the $5 mark. You know, $5.05 max, don't you think? ;)

Yes, Michael Simpson has an interesting approach to the market. You've got to figure those are tight margins, though. You spend 10 minutes per, supporting a product like that, and everybody looses. So more power to him for trying.

And again, you are right. Kronos is ~$7 and not a system. Any additional anything, crystal, ceramic resonator, low voltage detector, RS232 buffers, LED's, regulators, reverse polatiry diodes, pull ups, PCB, solder even, and the system price goes up.

Short of a bare micro with nothing but machine code, you've found a chip very close to the mythical $5 system, but cost is off by atleast 2X to make even the most rudimentary system out of it.

Again a very close entry, but still not a system. And as you say...

I really believe in having a stache of micro around you're familiar with and "at the ready" to use. Even if you just use them for testing or signal generation of some timing patern you need, you can save lots of time, which usually in engineering circles translates to buckets of money. The cost of the micro is completely inconsequential when compared with the cost of your time not to have it.

Of course, I'd wish it was my processor everybody would fall in love with, but hey, at least the principle is very sound! ;)

Yes, I agree, and also agree with the word "us".

Sorry for the diversion, but this brings up a memory. In the mid-60's I suffered a serious set back in my electronics program. The hogs broke into the shed where my carefully hand dissected TV parts were kept. They seemed to prefer those capacitors over anything else. Back then, circuits were hand built, and it wasn't a circuit if it wasn't mechanically twisted on _before_ the solder flowed. The pigs ate about two years of manual effort unwrapping and recovering those caps. I was devastated. Talk about cheap... I was mad about my capacitors. My dad, on the other hand, was worried about his pigs ability to survive the digesting capacitors. Anyway...

Oh, same here. It's not the customers who complain. Its those who don't intend to become customers, that have the $5 micro, publicly waving its legend at you.

Agree absolutely.

Yes, that's true. But. What I'm suggesting, is, how did it come to the point that our lives aren't even work $5 an hour? I mean, doesn't that $5 micro cost at least 10, maybe 20, hours or more time out of our lives, over buying an assembled one with support and just sticking it in?

Are any of us getting younger out there by working on our robots?

Are any of us doing significantly better and more abundant robotics for having taken many hours longer and saving a few bucks? or does that go the other way 'round?

I'm saying, the same principle you already acknowledge for work, still applies, when the end result is working robot vs. no robot working any time soon. Even as hobbiest, we're using a false economy, no manager accountable for results would accept.

Good point on power supply you make. Somethings DIY just can't reach the point of "well done".

And that is sad isn't it? to be so cheap, we consume your life's blood, the only thing we truly have a limited amount of, time, and in the end not even have something polished? We spend our time reinventing the wheel to save a few bucks, and get far less done, at a far greater price than our bucks.

That's the part I'm suggesting is the tragedy of the mythical $5 micro. It steals what life could have been, on the cheap.

Okay, but it's terrible english.

-- Gordon

You're right. We. "Us are ..." doesn't make much sense, my bad.

-Brian

: Yes, that's true. But. What I'm suggesting, is, how did it come to the : point that our lives aren't even work $5 an hour? I mean, doesn't that : $5 micro cost at least 10, maybe 20, hours or more time out of our : lives, over buying an assembled one with support and just sticking it : in?

Well, since you ask. :-)

I've run into both cases. I've tried to build something myself, and ended up paying more in parts then I would hvae on the unit (and do I ever wish I had bought that motorized lazy susan when H&R had it . . .).

On the other hand -- It woud take a LOT to go from a $7.99 ATmega16 to a $99 board. Yes, I spent $80 on a stk-500 -- but I've built four projects with it, each of which as a $8 controller in it. I've also fried 2, and would be much more upset if I had blown two $99 boards.

Also, with sites such as AVR Freaks, you don't actually have to write most of this yourself. There are enough pre-written modules that you can take an $8 micro, add some existing software, and have PID going in no time at all.

Also, for me, any time spent IS the goal itself, not the means to an end. It's a hobby -- building is the fun.

Yes, seems like for the most part, a $10 microcontroller is a more realistic aim. However, you might want to take a look at Picaxe microcontrollers at

They also can be purchased in the United States through You CAN get an

8-pin Picaxe 08-M microcontroller (based on pic 12F683) for under $5.00 USD. I have built a couple of simple robots with it. One using just one 08-M the other using three. For around $3.00 US for the chip, and making the programming serial cable yourself, and downloading the free software, you can have a working microcontroller based project operating, in a few minutes, for under $5.

I went to the first site and found near the top of the page:

The Amazingly Inexpensive PICAXE PICAXE-18X - A bit over $10.00.

So as you say, the $10 microcrontroller is closer to a truth. Yes I did find under $3 PICAXE-08 and PICAXE-08M. I was thinking they needed a resonator or low voltage detect, or what have you. Apparently not. Pretty simple to use. RS-232 "interface" via two resistors apparently.

So they have a snazzy basic compiler on the PC, and you download via serial cable. You get like 40 to 80 instructions depending on 08 or 08M. That about right?