What is a Propeller? What do you do with it?

parts-man73 · 2007-09-10 17:34

I hope people don't just read the subject line and think I'm an idiot....

I get asked this quite often by friends and relatives when they see me working with my Propeller stuff.

I never have a great answer for them, I show them video demos, plug in a few LEDs to blink, move some servos, plug in a temp sensor or the like, and they seem very un-impressed.

Anyone know of a demo that may impress the non-technical observer? For us on this forum, we are impressed by some things that others may not be, simply because we know what went into creating something like that ourselves.

One problem may be that others are used to their Playstations and PC graphics that are almost lifelike, and the graphics that the Propeller has to offer currently look quite antiquated in comparison.

Anyone have a killer demo that could be used to show people the power of the Propeller? or perhaps a YouTube video of something Propeller based that will knock their socks off?

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Brian

uController.com - home of SpinStudio

Post Edited (parts-man73) : 9/11/2007 1:20:11 AM GMT

deSilva · 2007-09-10 17:49

Brian,
I know this situation very well! And I have still no aswer to it.

What do we show in fact?
Borderline technology? Not really, that's what happens in the Top500.
Our own skills? Partly, but most people are more impressed by someone bending an iron rod!
Good do-it-yourself stuff? Well, if it is do-it-youself-stuff: A small cell phone? A high capacity mp3player? A fully automated home?

But most of the interesting things we do can be bought cheaper and smaller around the next corner.

Sometimes I think it's a little bit like the Paralympics - people say they are impressed what handicapped persons can do - what they want to really know of is high-performance sports.

hippy · 2007-09-10 18:03

@ Brian : Every single one of my friends who is a non-techie has always asked "could it become a killer robot army" whenever I show them some circuit I'm ecstatic over.

People tend not be impressed by circuits and stuff because they don't see the effort involved or understand how it's a stunning achievement, especially when they can get the same thing from the local Walmart for a dollar or two, or wouldn't want it themselves anyway.

Sometimes you just have to lie to impress; boot up with a Windows(TM) splash screen then show a desktop; "yes that tiny, cheap chip and these four AA batteries are doing all that, and if we had a mouse or a keyboard we could try running some applications

I've found the best things to impress are those which are interactive, sound and games particularly.

Oldbitcollector (Jeff) · 2007-09-10 18:35

Personally, I'm glad Brian is asking this question... It's very worthy of discussion.

I have invested in several advertisements announcing the formation of a Microcontroller Interest Group in my community,
and I've got to come up with some answers to these questions myself. (TOMIG: jeffledger.googlepages.com/tomig.pdf ) There are already several of us here that are planning to get together in "club" like fashion to expressly play with the Propeller, as well as dabble in Robotics. I expect a few of the "unwashed masses" to drop into this first meeting, and I'm sure these questions will be on their minds.

Like it or not, we live in a society that buys cheap from "walmart", expects playstation 3 level entertainment, and figures on throw ing out the technology they purchased within a year or two. The propeller attracts most of us because we would rather have something that has quality in it (Chip's years of development time), and we would rather be entertained (the other hobbiests here) by something that we made ourselves, however simple. I suspect that most of us have the same feelings about the level of waste, values, education, and choice of entertainment. [noparse]:)[/noparse] I'm betting that legos, erectorsets, and 8bit computers were common childhood toys of many here.

To me, the Propeller is electronics sillypuddy, able to be fashioned into anything I desire easily. My first vision of the Propeller was that of a modern microcomputer, a place where I could come to play in 8bit fashion, except that I get to us SD media instead of 5.25 floppy disks (which I have thousands). Since then I've begun to appreciate more mechianical uses for Propeller, as a couple servos have recently been added to my collection, the goal of learning to create my own robotic hand.

How do I explain this next week at the first meeting of our club? I'm still working on it.
Is this another area where you either get it, or you don't?

Aha! UPS just dropped off my Magjack samples... Time to go back to play.. [noparse]:)[/noparse]

Oldbitcollector

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Buttons . . . check. Dials . . . check. Switches . . . check. Little colored lights . . . check.

— Calvin, of 'Cavin and Hobbes.

mcstar · 2007-09-10 21:51

I think you have to have a need or a want to truly understand the power of what the propeller represents. Personally, I purchased a robot kit over a year ago (the ER-1 from evolution robotics) for about $200. My intent was to extend the program to where it could map its environment automatically. I wanted to then label the map and be able to give it directions like "go to kitchen, turn around, return to living room" etc. This is for a prototype of a larger product that has commercial application. However, with the software·included in the ER-1·this functionality was very difficult. The package was limited and focused on being used extensible on in a very limited fashion. Plus, you had to have the windows OS running in order to run the software. Windows was also required because it contained the drivers needed to communicate with the very powerful motor and IO control module. This turned out to be a fatal flaw in the way the product was designed.·This meant an entire laptop or very expensive tablet PC had to be toted around by the robot. Think of all the waste, the keyboard, screen, harddrive, all this hardware is really not needed by the robot application. This added tremendously to the cost, weight and size of the completed robot.· It also·hurt the Cost/Performance/Power equation to the·point that it limited the commercial viability of products built on top of it. I had the idea to replace the laptop with something compact and powerful, yet specially designed to reduce the weight, power requirements and cost. When I first found the Propeller back in January I began to believe that might be able to serve as the brain needed to make this robot possible. Now, I've redesigned the chasis making it less than half the size of the original. My entire "computer" fits in the palm of my hand and runs literally off 4-double A's. Even with a small LCD screen it has power for days on a single charge. It miserly consumes just the power needed for the current task at hand and intellegently powers down processing power not needed (ie shuts down cogs). The propeller is connected to a vinculum usb host which gives it the ability to communicate with nearly any kind of USB device (just add software).· ·All this and the cost of my propeller and associated hardware is a fraction of what the original robot kit cost! Compare that to a $1500 laptop!· A side benefit from all this is that the process of creating the solution involves learning about things that (in the windows world) would have been left to someone else and just linked to or consumed.· That meant your product was tied to someone else's liscensing requirements and could be changed by them at any time.· UGGGGH, none of this is good for time product creators.

I fullly believe that this huge improvement in the Cost/Performance/Power equation makes the product commercially viable even in a competitive market. This is just one example of how the propeller can be used to "impress"... it sure impresses me!

Post Edited (mcstar) : 9/10/2007 10:01:04 PM GMT

Graham Stabler · 2007-09-10 21:55

First ask yourself when the last time they showed you something impressive!

Its not what the propeller can do so much that impresses me but what it allows me to do. Its not the graphics demo but the fact that with a few clicks and fewer resistors I have a processor outputting video graphics, normally that's a project in itself. And then you still have all that processor left over!!

Graham

mirror · 2007-09-10 22:35

I own an impressive piano - and have been teching myself to play for the last 12 years. I'm not a virtuoso, and if anybody where to listen to my playing they wouldn't be struck with awe. But it gives me great pleasure to discover the music of Beethoven, Debusy and Rachmaninoff for myself. So it is with the propeller - what we produce may never be masterpieces, but it is the process of discovery that's important!

I think that is what we share in common on this forum. We're glad when somebody else makes a little discovery. We are impressed by that which others may find "un-impressive".

I think we should learn to be impressed by anybody who is exploring new things in their lives and making new discoveries. I think the only un-impressive people are those who have given up learning new things.

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_Mark · 2007-09-10 23:33

My guess is, when showing existing demo's of what a propeller (or say, the Hydra) can do, if that does not impress some people, chances are they don't really know a lot about microcontrollers. Nothing wrong with that. The "problem" is simply that they can't relate to it. Similarly, to be impressed by certain kinds of art, movies, music, or whatever, sometimes you have to know at least a little bit about it.

The thing with technology is, of course, that people expect it to be immediately useful to them. It's not easy to see the usefulness of a propeller when comparisons are made to modern PC's or other high-tech stuff, unless one understands that it is like comparing apples and oranges. You could tell them that, for example, comparing the propeller to a mobile phone or GPS car navigation system, would be a bit closer to reality. With the right components and software, the propeller could well be at the heart of many such devices (and robots of course, but that might not be a strong argument for people who don't care about that). You could add that the propeller, when compared to other microcontrollers, is one of a kind and brings a combination of power and relative simplicity that has impressed many experts, and yet has made it very accessible to the casual hobbyist. At a low price.

Which brings us to another point. For many people, playing with electronics (or robots or microcontrollers or model trains, or whatever your area of interest is), is simply a hobby. The propeller might be a pearl to someone who has such a hobby, and a pebble to someone who doesn't. Likewise, some people love to paint, play the piano, or collect stamps (no pun intended). And likewise, the people who are most impressed by a hobbyist's painting, or song, or an obtained stamp, will most likely be people who know something about it, who have a common frame of reference. People who understand it is beside the point, that one could perhaps buy "better" paintings, songs or stamps in a shop down the street.

If a propeller does not impress one's friends or relatives, that's alright. It's your hobby, it does not have to be theirs, if it just doesn't do anything for them. I'm not as impressed by motorcycles as some of my friends are, but I still share in the joy when one of them buys a new one. If you can show something cool that you've made for yourself, with the propeller, and of which you are terribly proud, perhaps your friends will share in the joy as well, even if they're not as excited about it as you are. But I don't think there is a "killer demo" for the propeller, or any other device, that would truly impress someone who wasn't already into that kind of thing.

To make this post even bigger

here's an example out of my own personal life in the last couple of days. The background story is, I used to be a software developer, but I am currently in training to become a bus driver (it's true!). When I told a friend of mine that my propeller had arrived, he was happy for me, but he doesn't really know what it is or what it means. What he does know as well as I do, is that my usual driving style would not be appropriate when driving a bus

and that I am currently practicing in my own car to drive more relaxed and smooth. When I told him that with the propeller, an accelerometer, a buzzer, and some batteries, I could create a device that would warn me whenever I break or turn a corner too abruptly. Trivial as it seems, he instantly felt that was pretty cool!

Fred Hawkins · 2007-09-10 23:38

1) there's Chris Cantrell's text game that was in published in the August Circuit Cellar

2) then there's Franz's internet page (which could be made flashier for us to brag about). Everyone believes in the internet.

3) Peter's box, (released yet?), which does all sorts of stuff and looks very competent, ie hot.

4) no example, but a common hack: an line of led's that use persistence of vision to create text messages. Be sure to have a keyboard (and software) that lets you change the text.

5) get 4au's oled package and store last year's photos. Bore them to death.

6) pester Graham for a link to something cool that he built -- ad hoc flat bed printer?

7) the OS drone demo video: http://forums.parallax.com/showthread.php?p=662235

Everything is more impressive if you do it on a plain breadboard in real time with a minimum of stuff. Practice! Real magician's have patter, a rap, know where they are going and what they want to do. Script it out, prep the demos ahead of time. Think snake oil. Pretend you have a hole in the wall store that sells neat stuff. Sell the sizzle.
Show em a sd card and then use it. (Only camera companies know how to use sd cards.) Try not to use too many breakout boards unless you wirewrap them. WireWrap
anything, even add do nothing wires for the "wow, complicated!" factor.

For instance for Cantrell's game, add the sd card to a breadboard by plugging the breakout board wires in front of the audience. Then add the keyboard and tv/vga interface at the same time -- a couple resistors and the accessory plug kit. Then take your desktop's keyboard off the pc and slap it on. Run the rca cord to a regular tv. Get it the game going, let em play for a minute, pull the sdcard interface, swap out the eeprom and show em something else.

Oh yeah, try to use just one 9 volt battery that you clip into the board as you set up. Have the power circuitry all set but add the power on led after the battery is on. Avoid walwarts because they dilute the magic -- the black transformer and wire yell not-built-here. Plus they know too much and are telling the prop how to do all the things it does.

Consider getting a lab coat like Jaguar or Mercedes·repairmen.

Post Edited (Fred Hawkins) : 9/11/2007 12:12:24 AM GMT

Fred Hawkins · 2007-09-11 00:08

Aha! Arithmetic. Anything with arithmetic.

Oldbitcollector (Jeff) · 2007-09-11 00:13

Fred, Your post has left me in stitches! ROFLOL! Seriously, the ideas of building a Prop setup in front of folks and removing the wall-wart are a good idea, and I will use them next week when I demonstrate the Propeller in all it's glory. [noparse]:)[/noparse]

Oldbitcollector

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Buttons . . . check. Dials . . . check. Switches . . . check. Little colored lights . . . check.

— Calvin, of 'Cavin and Hobbes.

Ken Peterson · 2007-09-11 00:58

Wish I could convince my wife that my time spent playing with my propeller is well spent! She sure doesn't get it. "You already have a computer, why do you need another one??"

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The more I know, the more I know I don't know.· Is this what they call Wisdom?

parts-man73 · 2007-09-11 01:16

Ken Peterson said...
Wish I could convince my wife that my time spent playing with my propeller is well spent! She sure doesn't get it.

I didn't want to mention any names, but she was definitely in the "friends and family" category that I mentioned in my first post in this thread. And she needs to be convinced that not only my time is well spent, but I also have to justify the charges on the credit card for Parallax, Spark Fun, Mouser, etc

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Brian

uController.com - home of SpinStudio

sam_sam_sam · 2007-09-11 01:27

Hi Everyone

I understand what you guy are talking about in this post.......................................

·And i know that what i used
was not a Propeller but i though that i would share it any way

Here is what happen to me the other day when some people·came to·my house and i just installed a automatic chlorine feeder to my pool
And they ask how many hour i ran the pool·pump ·i said well it run for 6 to 7 hours a day

Well where is the timer· they said to control the pump i said on the wall.............

Then said well how do you set the clock

This where i have a Basic Stamp with a Time Chip ( the DS1302 ) and a led to see if the sun is out playing and if so then· turn·ON the pump for an hour and OFF for·an hour and so on

Then said well you can buy one at the store I said yes you can but those you have to reset the clock when you lose the·power..... This one you do not have to do anything·there nothing to·reset you just plug it in away you go
·
This part of what i said caught there eyes
·I would not be surprise if he dose ask me to make one so he can do the same thing

·

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··Thanks for any·

·that you may have and all of your time finding them

·
·
·
·
Sam

Post Edited (sam_sam_sam) : 9/11/2007 3:26:33 AM GMT

Fred Hawkins · 2007-09-11 03:09

The important thing to stress is that the doing of things is the fun. And that fun doesn't neccessarily come in box just bought at the mall.

So sayeth my better half after looking this thread over. (Trust her, she's programmed main frames since May 24th, 1966 when she took a three week course on assembly*.
*NCR 315 assembly. Hot (s-word expletive) stuff, J sez)

Kevin Wood · 2007-09-11 03:43

_Mark, your friend might be interested in this:

http://forums.parallax.com/showthread.php?p=609533

jamodio · 2007-09-11 04:21

Ken Peterson said...
Wish I could convince my wife that my time spent playing with my propeller is well spent! She sure doesn't get it. "You already have a computer, why do you need another one??"

I've the same problem if you find a good answer let me know. On a side note it took me a while
to convince my grandmother not to step on my ICs when they fall in the floor, sometimes they
may have "bugs" but are no insects !!!

Cheers

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- Jorge

Duffer · 2007-09-11 06:08

I don't know if this will help to get the "uninitiated" interested in the Propeller (or any other micro controller)·or to understand why we do this, but here goes (warning: this is going to be a bit long, but there is a point).

I was having what I thought was a problem last·summer. Too often, I thought, I would go upstairs or into a room and realize I didn't know why I was there.·I spoke to my doctor and she said that I probably just needed to get my brain out of its rut and make it do something different. While discussing what that "something different" might be, I mentioned that I had enjoyed the electronics training that I had gotten while in the Navy (didn't end up using a lot of it, but I found it interesting). Long story shortened, I decided to re-teach myself electronics from scratch.

In November of last year, the company I was working for announced that, in conjunction with the upcoming holiday party, they were having a tree ornament contest. Teams or individuals would submit their creations for judging at the holiday party and the winner would receive a $50 gift certificate. Since the judges were to be the three managing partners (all from tech backgrounds),·I thought something high-tech might be just the ticket and what would be more high-tech than a ROBOT! My search for a robot "base" led me to Parallax and I purchased my first Boe-Bot around the end of November. In about three weeks, I built "an autonomous, tree-seeking, self-hanging tree ornament ". It was the hand-down winner (the demo was highly contrived and actually worked maybe·one in three tries). Certainly no something you would find a Wal-Mart (their's would probably work every time).

I·have since gone on to experiment with more complex robots and recently took up the Propeller challenge, but the point (finally!), it that it has worked. My mind is sharper, I don't have the lapses that I was having last year and I am thoroughly enjoying my new hobby/therapy. The wife doesn't complain (too much) about the expense (it's cheaper than psychiatric treatment) and she sees that it makes me happy.

I think that one of the things that you might do when asked the tough question (see thread subject line), is·ask some questions of your own: "Have you ever wondered HOW some of the things you use every day actually work?" , "How does you oven KNOW when it's reached the temperature you set?",· "How does you car KNOW when the tires have lost traction and started to skid?",· "How does you microwave KNOW what buttons you pressed and what they mean?" and you can probably come up with about a hundred more. The answer, of course, is micro comtrollers and sensors.

Some people will want to understand how the technology they use every day works. Those are the people that you want to attract to your "club".·Having a way·to learn how stuff works and to take some to the techno-magic out of the technology we use, will attract the kind of people you want.

Lastly, when someone sees one of my bots or other projects and asks: "Did you do that yourself?", my killer answer is: "Yes, and so can you".

Steve

ErNa · 2007-09-11 10:19

Propeller is a gym for those, who already have muscles !

Mightor · 2007-09-11 11:00

ErNa said...
Propeller is a gym for those, who already have muscles !

Or those who don't care for them [noparse]:)[/noparse]

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| To know recursion, you must first know recursion.
| I'm afraid I might be phobophobic.

Fred Hawkins · 2007-09-11 12:58

"An autonomous, tree-seeking, self-hanging tree ornament " sounds as good as the under-the-bed-monster-killer-robot. Got a link?

crgwbr · 2007-09-11 13:27

It certainly isn't an easy talks to show others what the propeller is capable of, or why it's so amazing. Telling them that it's a 8 core multiprocessor that runs at 160 MIPs just doesn't cut it for some reason. Just the other day, a non-techie friend of mine stopped by my workplace; seeing a very industrial looking box setting on my desk, made him ask me what it was. Since the project was only half-built, about all I could show him was a couple LEDs flashing on the cover and a few air valves turning on and off (and then blowing papers all over my office, I had forgotten that it was connected to a 120psi airline). He wasn't that impressed. It definitely wasn't something that you could go to walmart and buy, but sitting on my desk, half-built, I couldn't show him what it could really do.
I opened the box to show him what was inside, a PropPLC I designed and hundreds of wires going all over the place (hadn't had time to clean it up yet); this was what impressed him. Long Story Short, sometimes its the way a project looks that will impress a person, not what it can do. But, at the same time, it doesn't hurt to "explain" some of the more complex aspects of the project in a way that they will never understand. While you are doing this, they will be thinking nothing but, "Wow, he's smart." lol

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My Blog: Prog | Electro | Mech

I would love to change the world, but they won't give me the source code

People say that if you play Microsoft CD's backwards, you hear satanic things, but that's nothing, because if you play them forwards, they install Windows.

I spent a minute looking at my own code by accident. I was thinking "What the heck is this guy doing?"

The Wangster · 2007-09-11 14:25

Andre LaMothe will be here shortly with a post lamenting about how when he was a kid,·a dedicated hobbyist·could build bleeding edge technology in·his basesment, and nowadays kids are spoiled with their 3 GHz dual core PCs and lifelike realistic games and nobody bother to do anything themselves anymore.

Anyway, I'm too young to remember the 70s and 80s, but I still find retro hardware cooler than modern stuff.

ErNa · 2007-09-11 21:37

A propeller is a multiverse in a pocket!

With a propeller, you can watch a computer watching a computer that watches five computers!

Ken Peterson · 2007-09-12 01:53

I don't know why that makes me laugh, but it does.

When I got my Commodore 64, I got the "Mapping the C64" book and I also studied the schematics. How lucky I was to have such a thing! How many here have (or had) a Commodore 64?

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The more I know, the more I know I don't know.· Is this what they call Wisdom?

Duffer · 2007-09-12 05:05

Ken,

I went the Atari route, but I know what you mean.

My first was a 400 (membrane keyboard, cassette tape for storing/loading programs), next, the 800 (real keys! and a hacked 5 1/4 inch floppy drive), then the 1200 and 1600. The 800 was then converted into a "development machine" with hardware debugger, "big time" 6502 macro assembler and UV eprom burner (I wrote a couple of commercial graphics apps with a friend that did the hardware side).

I don't mean to turn this into a nostalgia thread, but the point is, getting ones hands on those machines and having access to real computing power on the kitchen table was exciting stuff. I've rediscovered that kind of excitement with both the Stamp and the Propeller.

I think there are a lot of people out there that want to know what goes on inside all those high-tech gadgets we're surrounded with these days. Not with the idea of building a better iPod, but with the possiblity of building a working MP3 player with ones own hands and understanding how it all works (as an example). Turning a technophobe into a technophile is a beautiful thing to watch.

Steve

Post Edited (Duffer) : 9/12/2007 7:32:54 AM GMT

Mightor · 2007-09-12 05:05

Mine is down in the basement, together with an Amiga 500 (with PC emulator board + 2x floppy drive). Not even sure if still works.

Gr,
Mightor

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| To know recursion, you must first know recursion.
| I'm afraid I might be phobophobic.

Fred Hawkins · 2007-09-12 05:32

Mightor said...
.... Not even sure if still works.

It probably works better than any retired Windows·pc·with a·used-up registry. My Atari ST almost never crashed and I had to screw up big time to bring down my TI99-4a. Those things were engineered to work for kids not to·give up·with a blue screen. Did I mention boot times --- ah -- never mind.

Beau Schwabe · 2007-09-12 07:25

Duffer,

I don't think I could have expressed it better myself... "That feeling" is hard to find, and when you find it you don't always realize it until it starts to go away. I too have strong Atari roots, and experienced a similar lineage that you describe.

I've experienced the same question several times over the years, and most often I find myself describing or relating "what a microprocessor" does by comparing it to things that the other person uses on a regular basis ultimately convincing them that if it weren't for "nerds" like myself, you wouldn't get to play with your neat little gadgets.

The Propeller, SX, BS2, BS1 are building blocks that allow you to·explore an idea or an invention in a tangible way. If it weren't for tools like this, many ideas would never leave the paper.

"Prop Rocks" - Spin Candy for your mind - Experience it!

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

Post Edited (Beau Schwabe (Parallax)) : 9/12/2007 7:29:55 AM GMT

Duffer · 2007-09-12 07:28

This is for Fred H.

I was able to find a video of the self-hanging tree ornament bot. View at you own risk!

It used a PING))) sensor and bracket (with a tiny Santa hat and the "eyes" peeking out). Quite a sight, believe me!

http://www.youtube.com/watch?v=ft3QVt7nHwY

I'm only going to leave this up on YouTube for a few days.

Post Edited (Duffer) : 9/12/2007 7:42:54 AM GMT

Fred Hawkins · 2007-09-12 09:54

Duffer,

Thanks, it's as you said, a great (my adj) winning idea, a bit contrived and looks in low res a lot like a turkey. That tree, however, is suspect.

Fred

What is a Propeller? What do you do with it?

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