Lots of hobbyists seem to frequent the Microchip forums, and are using the Microchip assemblers and compilers. Free versions of the compilers are available, that are suitable for use by hobbyists, and for many professional applications, as extensive optimised peripheral libraries written in assembler are available. Using those libraries makes everything very easy, even for beginners.
I have one of my "lunchbox" projects which is an Arduino. I have a separate PAL (B+W) video chip so that it doesn't steel all of the '168's ram. This is TellMate by BatSocks, which comes as a shield normally, 40x25 is ok for debug output or a bit of retro.
Most VGA is very limited, mostly because of the smaller internal RAM.
Arduino is the defacto standard in the educational/hobby environment because it was designed at the outset to meet specific goals ie.-
"The project began in Ivrea, Italy in 2005 to make a device for controlling student-built interaction design projects less expensively than other prototyping systems available at the time."
The Arduino is a complete system/eco-system whereas the Prop is basically a chip.
In re-thinking it, I'm sure the biggest obstacles to active interest/adoption of the Prop are:
A) Lack of common programming language*, ie Basic, C, C++ which requires an unknown language called Spin. I think this is overlooked by many as a mere trifle.
I don't think people stop and think about what going the proprietary route means. A decision must be made by the instructor as to whether or not he/she wants to expend x amount of time learning a new language. Teachers are busy/lazy as anyone else, and expecting them to learn a new language to teach a course versus using what they probably already know (Sketch/Processing) is not what I would be willing to bet my paycheck on. Add to that the very real fear that they would look too novice like to the students they are teaching, and.....
*Yes, I know other languages are available, however its not really far to use as an example as its not what is Officially spec'd by Parallax, and not really known outside of the forum I think.
A multi-core interrupt-less controller..... I can see the head scratching by a potential instructor, heck, I've seen 2 Principle Systems designers (ARM) who are in the Hobby-side as well scratch their heads. One asked me "what does -not- having Interrupts ultimately buy me as a designer/programmer? Interrupts are well understood and have been used for 40+ years to build basically everything in the world." Again, these are comments by designers who are in the hobby, not myself, a novice.
I wonder if the one, best thing Parallax could do to increase interest and adoption of Prop would be to draft in the Arduino wake.
Just hire or contract someone to get Processing and Wiring ported to support the Props. Or, fund some of the OSS dev's?
Does anyone not think the Prop would be far more attractive to instructors, students, and the Arduino masses if it used a similar language and environment? Assuming it is technically possible.
Imagine if it was magically made available, if just 10% of Arduino users took the now very small baby step over to the Wiring/Processing Prop? And imagine if every year, as new Uni students come in that additional 10% reoccured, and then 10-20% second/third year students needing more power picked up on this Prop-thing.....
It seems like this is happening in part already organically with the Prop ASC and other efforts. I think Parallax could make this happen at warp speed if they put some resources behind it.
It would only make uptake of the Prop/Prop II that much easier from a Buy-in decision as less expended time, familiarity, etc, and more successful to the existing Prop community and Parallax as a company.
Hopefully no one takes offense at my comments, as I think the Prop's are beyond cool. I just see a number of obstacles to real adoption that could be ameliorated.
The Prop, to me, still has that hidden away "engineers" niche. As many before have lamented, if only that breakthrough could happen for the Prop. The lunch box I carry around is a demo board sort with a breadboard on the top of a Betacam SP tape box, it was an Arduino before. The almost built in periferal support made it a staight choise.
Koehler, Processing is a language for PC built on top of Java. It talks to Arduinos over the serial port and can talk to the Propeller over the same serial port. Wiring uses Processing for its IDE on the PC. It cross compiles C and C++ on the PC to produce a machine language file for the AVR microcontroller on the Arduino board. That is probably not feasible for the Propeller. I don't think that Spin is the killer for the Propeller. There is a free Basic, a free C, and a commercial C.
As you work through the labs and assignments with the Arduino, do the same labs and assignments with the Prop.
I think analog input might be the only thing that the Arduino platform has over the Prop chip in terms of hardware capabilities. Get an MCP320x chip and use the excellent drivers at obex.parallax.com.
Once the professors see how easy and powerful the Prop chip is, maybe in the future they will consider introducing it in the curriculum! Better yet, they'll have your documentation via lab/assignments for the Prop chip as a reference.
You probably won't get to use the Prop officially for your assignments, but you'll learn a great deal, and probably come away with the conclusion that the Prop makes a lot of the tasks of schoolwork assignments TRIVIAL! (yeah, I said it, trivial). Of course, the non-trivial stuff comes from your actual application logic and you'll have much more fun developing that portion than fighting with the deficiencies of antiquated microcontrollers (yeah, I said it, AVR, PICs... antiquated compared to the Prop. Okay, maybe if you're producing hundreds of thousands of a particular product you might be better using the cheapest PIC possible, but how can that be fun? ... or if you really need to just do something very very simple then one of the many of hundreds of low cost PICs might fit your need).
As for the PIC comparisons, I'm actually glad that we studied the PIC in college, as it has helped me to understand the old way of doing things: setting up registers, banging your head against the documentation (even supplementary material) to understand all the various modes of the CCP module, messing with interrupts, etc ...
I am beginning to thing that the Arduino's success is all due to 'latte' effects - the average user appears to not be some an engineer as someone that likes Italian style. If it were not for the Italian origin, it may have not gotten lift off. Many of the people involved in Arduino seem to lack any knowledge of what went before the Arduino and the foundations of its success.
Yes PICs are good, so are AVRs. SXes were great because they were faster than PICs. But the peer-to-peer culture behind a product is where the average learner develops their product loyalty and preferences. Unlike most big companies (e.g.; Microchip and Atmel), Parallax has always been devoted to peer-to-peer support for the newcomer.
I repeat, Parallax's success in the educational market place has always been about their support and in particular their publications. Admittedly, they have tended to ignore C. But that has been because the C compilers that were any good were quite expensive and beyond the reach of the student population until recently.
And there are real questions of the need for C in a micro-controller setting (study the history of C and you see that it has based its success on cross-platform portability of programs for traditional mainframe computers. The idea was the you didn't have to buy software from the same company that sold the hardware. You could port existing software to different hardware as your company evolved.)
It isn't true that Arduino is the 'defacto-standard' of the education environment. Arduino has come into its own only because inexpensive and free C compilers for AVRs became available. But it does seem a rather odd and lop-side educational environment that promotes developers as 'artists' rather than competent programmers and engineers.
Prior to Arduino, Parallax pretty much has been the 'defacto-standard' and pace-setter of the educational micro-controllers. But with success, you eventually get attention. And that means competition that apes your key features of success - such as free compilers and fundamental publications. The big companies decided to finally provide free or cheap C as they couldn't sell the stuff for thousands of US dollars that they wanted to. New customers were just not appearing as they were ignoring the educational institutions and student populations.
So please, don't slam Parallax on its home turf. It has been quite generous and hard-working in providing value to students -- long before Arduino. And regardless of what Microchip or Arduino do, I suspect that it will respond well to its customers needs rather than merely try to ape the competition. Texas Instruments is the latest newcomer in this arena. I wonder how Arduino will hold up against Texas Instruments if their prices are undercut? Everybody loves a freebie.
Interesting comment about the "'latte' effects". I'm not sure that's a bad thing though. As far as I can tell the Arduino concept is targeted at non-engineer types. Rather like the target market for Apple computers verses the IBM PC. The former let's non-techies get on with stuff, the latter enabled techies to hack easily.
C compilers, or indeed any compilers, used to be expensive. Then along came Richard Stallman, his philosophy on free software and his GNU C compiler. Those who wanted to use AVRs targted GCC at the AVR and lo it became possible to make the Arduino.
Whilst C was about the first language the enabled cross platform portability it for sure was not targeted at mainframes. Indeed C and it's accompanying operating system Unix were designed to be small compared to what was being planned at the time (See Multics). It was to be used on mini-computers with not much more resources than a modern day micro-controller. The PDP-7 had an 18-bit word length, and its standard main memory was 4K words (equivalent to nine kilobytes) but upgradeable to 64K words (144 KB).
The big companies decided to finally provide free or cheap C as they couldn't sell the stuff for thousands of US dollars that they wanted to
Again we can thank Richard Stallman and the GNU crew for that:)
It uses a similar approach to programming, making it very simple, except that the compiler is accessed via the web. It works very well, and is even easier than the Ardiuno to use. NXP is giving them away to entrants to the Design Challenge competition! I got mine yesterday, but NXP had already given me one for running the LPC2000 group. I'm going to the Embedded Live show in London next week - ARM and NXP have stands, and I wouldn't be surprised if I get another one.
It is interesting that these people don't consider themselves engineers and yet are quite fixed on C as a programing language choice. C/C++ demands more effort than SPIN, a steeper learning curve.
I have been going over Andre LaMothe' Hydra Manual - Chapter 15 and that is a very good introduction and overview of SPIN. Some things I had not noticed or forgotten stuck out. In fact, I think this presentation is much better than the Propeller Manual for an initial entry point, not so dense with details.
The foremost is that programmers in general use about 10-15% of a language. I suspect that this has strongly determined Parallax's approach to constructing programing languages. All the abstractions of C and higher Object Oriented Languages are pretty much left out. I suspect Arduino fans want a 'warts and all' formal programing language, rather than something less. A lot of academics are likely to prefer to teach such as there is more course content as well.
And like the BasicStamp, the Propeller doesn't get into data structures. Rather than have a full set of features for manipulating data, it is quite simple - pretty much one-dimensional arrays. This is certainly a philosophical influence. You can have that stuff if you want it, but you have to build it.
And another philosophic generality is akin to Dr. Dobb's Journal motto - "Running light on over byte". The Propeller is frugal in RAM and ROM while lightning fast in speed. It is an 'clean slate' that must be filled in by imagination and sweat rather than a system of hardware that just requires one to get their ducks in a row.
The new C3 board offers more of the 'ducks in a row' feel that Arduinio-nauts prefer. But it still offers the 'clean slate' of the Propeller when that is required.
As I've said before, these kinds of debates are endless. Mostly it is about one's perception of value. And as of yet, I just haven't found books and documentation that I enjoy for the Arduino.
I have never bothered to look at the Arduino before because, well, it's an AVR, been there, done that. It's programmed in C/C++ , been there, done that. What's the big deal?
But since finding out that we can possibly run Arduino style "sketches" on the Prop via Zog and since we now have the Prop A.S.C. board I started to sniff around at what Arduino really is. I have to say I'm impressed with the simplicity they have come up with as an introduction to the world of embedded control and micro-controllers.
Firstly "these people [that] don't consider themselves engineers", i.e. Arduino users, are not fixated on C/C++. That just happens to be what the Arduino developers have provided.
C/C++ demands more effort than SPIN, a steeper learning curve.
Normally true. But that is the point of the Arduino world. Arduino users have been exposed to a subset of C/C++ such that they don't get overwhelmed by detail when starting out. When writing your first Arduino "sketches" you don't have to know about "#include blabla.h" or "int main (int argc, char* argv[])". No you just write simple code that has immediately obvious meaning and it works. The Arduino documentation that I have seen only scratches the surface of C++, everything is kept as simple as possible for the beginner. More on this later.
I suspect Arduino fans want a 'warts and all' formal programing language
I suspect that those new to programming and new to micro-controllers and whose primary aim not programming but to get some creation working don't care a hoot about "formal programming languages".
Now, imagine you have never picked up a micro-controller before and you have never programmed anything. You have some vague idea what it's about so you find out you can by an Arduino or a Propeller board to play with. Or maybe someone you know, or your school is about to teach you your first steps.
A simple first task might be to read the state of a pin and get it printed on your PC's screen.
The Propeller beginner will be confronted with this:
Quite frankly despite the fact that C++ is a vast and complicated language the Arduino beginner gets started with a lot less strange and confusing stuff than the Propeller beginner. Bingo he's hooked.
That, I recently discovered, is the simple genius behind the Arduino.
I follow you up to a point. But.... Can you please explain 'void' to me?
I haven't really learned C/C++ and that immediately seems counter-intuitive to me. After all the everyday means is 'invalid' or 'empty'.
It took a lot for me to grasp "main()" in Visual Basic as well.
At some point it seems any computer language demands that we accept that 'this is what we do to make that work' and just try not to look too closely as what the words are supposed to me. Later, you will understand it.
I must say that it is a tribute to the Propeller that you can port Arduino code over to it.
Programing in C/C++ has cache, prestige value. It is something like this. If you care a Calculus text with you everywhere you go, people will comment that you are quite intelligent. But you don't have to read the book to gain the recognition.
One can argue that the separate sections in SPIN actually clarify rather than complicate is being done. Reams have been written of the obscurity of C code. Nonetheless, you do indeed demonstrate that once we master and fully understand something - regardless of how complex - it is crystal clear to ourselves.
'void' simply means that the function doesn't return a value, or it doesn't have a formal parameter if it is within parentheses. C is a typed language, and functions either return a typed value (int, char or whatever) or don't return anything.
Things are even easier with the mbed than with the Arduino:
"void" That infinitely huge and dark space into which things can get dropped never to be seen again. Rather like any values coming out of the procedures "setup" and "loop".
You might also have asked "what on earth are those empty pairs of brackets "()" hanging around for? And what's with the semi-colons?
Point taken and you are right, pretty much all languages have junk that makes them work. Even human languages. Not sure what we can do about it, turns out that if you take the junk away the language becomes too limited to express anything non-trivial.
But both the Prop and Arduino have done a good job of making the baby steps less painful.
I must say that it is a tribute to the Propeller that you can port Arduino code over to it.
Yes, well, errr... That is still yet to be demonstrated. I'm sure it will workout for simple stuff, we shall see how far we can push it.
The Arduinos are very good for the layman. The shields, are those building blocks for any nifty project.
However, it's hard to get the Arduinos in SE Asia. I cannot find any distributors who ever sold these at all, while many of my students are trying to reach them.
They will be cheaper elsewhere, especially if you get clones.
Thanks. I would order a clone and test them first. Right now I'm a bit busy with the Propellers, but if I have some more time, I'll definitely give them a try.
Forgive me for getting a bit semantic, but when I was presented with two code segments, I couldn't resist. I suspect to the beginner, both are about as familiar as marks on the Rosseta Stone. And since the Propeller has code for the adjustable timing included, it seems that apples were once again being compared with oranges (for the sake of argument).
One thing that teaching English and studying Chinese since 1994 has done has to pretty much teach me how any linguistic argument turns the mind to mush. I got involved with Parallax and a BasicStamp because I wanted to compare my everyday linguistic knowledge with that of computer languages (possibly a big mistake). It has been very interesting, but after years of effort.... simply inconclusive.
Like Chinese versus English, C has its oddities and so does SPIN, but I would have to say that SPIN is not so philosophically committed to its own sophistication. (I hope that makes sense to others.) My main point was that Andre LaMothe's introductory overview of SPIN is a lot easier to read and understand why SPIN is the way it is. The Propeller Manual had to present all and everything, so it doesn't have that kind of presentation.
Void is indeed a 'type'. And C has many types that must be declared, along with a lot of other conceptual burden. SPIN tries to run on as little as possible of these types of things (it doesn't even have Strings).
There are good reasons for types in large programs. Void as a type seems to be an afterthought (Okay, I lied about never studying C). But since 'the devil is in the details' and C requires more details - it would seem to have more deviltry about it.
My biggest problem is that everyone that writes about programming feels the book has to be 700 pages or nobody will buy it. From my own experience, I have found I do far better if I can locate a good 150 page text to grasp the turf before I buy the 'doorstop'. And the next best thing is to have a Forum like this to ask why I am not comprehending the 700 page tome.
The C Programming Language, the bible as far as C is concerned, is only 272 pages, and about a third of that is the reference manual. It is also a very good introduction to programming techniques.
Of course that classic by Kernighan gets you not very far without "The UNIX Programing Environment" by the same author.
No, not so, "The C Programming Language" (K&R) by Brian Kernighan and Dennis Ritchie is the way I learned C back in 1984 or so. I only had MSDOS to run it on. It was many years later that I even saw my first UNIX system and certainly had not read any books about Unix programming.
I first tried to read "The C Programming Language" before MSDOS was available and trying to explore C via UNIX on a terminal connect to UC at Berkeley.
But the main point is that the text heavily relies on stdio.h, which I never fully understood without the second text. I suppose in a classroom setting the gaps are filled in by lecture and peer-to-peer support. But studying independently, having both texts really help.
And of course, the UNIX text explains quite a bit that Linux just presumes you picked up (but may never have).
Nah, all I had was the book, a compiler and an early PC and someone expecting me to produce code for money:)
The hard part was that it seemed to me that early C compilers were not very fussy about what you asked them to compile. Any old gibberish that you typed in would get compiled, without much in the way of warning or error messages, to something which inevitably crashed. Perhaps it was just the compiler I had, can't remember what it was now, but later C standardization seems to have straightened out a lot of that.
What was so hard about stdio?
Mind you, at the time a whole second book dedicated to printf might have been helpful:)
When I learned C using K&R I used a TRS-80 Model II running CP/M and a version of Small C, no knowledge of UNIX was necessary. The book explains stdio very well.
As I am a new Propeller user, I thought I would chime in on another thread I missed. I've been a Basic Stamp 2 user for six years, an Arduino user for one, and I'm pretty far along on my first Propeller project.
The strengths and weaknesses of the Basic Stamp 2 are well known, and I really like it. For my robot the 4000 operations per second is plenty fast enough, and there are so many examples available that I can cut and paste impressive stuff together in a few hours. I'll probably keep using it for this reason alone.
The Arduino's main strengths are C++, speed, a built in A/D converter, and C++. It's major weakness is that not all its pins are symmetric, and the RAM doesn't go as far as you would think. For example using a serial motor controller and a serial LCD at the same time is a challenge. But never discount the C++ advantage as many algorithms are available in it.
The Propeller's multi-core architecture is pretty darn nifty and I'm glad I gave it a try. It's like having access to a threads package and makes true concurrent programming possible. So I have one cog ramping six servos, another doing the inverse kinematic floating point, and a third orchestrating things. RAM seems plenty spacious, Spin is fast enough for my robot arm, and it has functions with parameters and local variables. I'd need a floating point co-processor and servo controller to do that with the Basic Stamp 2 or Arduino. The down side is that Spin is a bit odd, I can deal, but it means re-coding things like an inverse kinematic transform which I found C++.
I can get an Arduino Duemilanove for about £18, including postage. A Propeller USB Proto board will cost me £36 + postage. Arduino programming is very easy using what is, basically, C++, whereas the Propeller uses the very non-standard Spin language, and assembler is often required. I still maintain that the Arduino is more suitable for the stated application.
USMCinfinity:
There are several things you can do with the Propeller that can't be done with the Arduino: TV and VGA output, for instance.
You might want to look at the quickstart and Catalina and sphinx and propforth, etc.
The Propeller will probably need an external ADC chip, which will have to be assembled and interfaced to the sensors. On balance, I'd say that the Arduino will probably be easier to use, be cheaper, and offer faster development, especially if the users are already familiar with it. A 32-bit device with eight cores is overkill for that sort of application.
As far as over kill, I would not agree, should the cost be similar, which they now are, I would opt for too much to start with and allow greater flexibility for expansion later.
As a hardware/software guy with 25+ years experience, I just got an Arduino Uno board at Fry's and a Parallax QuickStart at Radio Shack. Although I got LEDs flashing on both within a couple hours, there's a world of difference in the usability of the two. If someone wants to get to a working gizmo as fast as possible, and the gizmo is a simple device that could be done with a hundred gates or relays or whatever, then there is no contest: Arduino wins by miles. The reason is in the approach that is evident in the code samples. The Arduino code is plain old C code, but what matters is it's legible code. The Parallax SPIN code is garbage code. I don't mean the language. It's the kind of code you write one night and a few weeks later you can't figure out what's going on. It's the kind of code you fire programmers for. And the hits keep on coming, second verse, same as the first. The hardware support is not standardized, no effort went into creating a platform, attracting users. There are now some Arduino compatible boards, but my Quickstart is compatible with nothing except remedial boards I can buy to try to make it fit other uses. That "Premier" debugging environment, ViewPoint, is a beauty. I fell in love. And then I realized it did nothing automatically, I'll have to instrument my code to see variables, and any programmer will tell you that's how you introduce new problems. But that's academic, as it doesn't work, it reads an old config file over and over, the docs are bad, and I can't get it to do anything except to load its own demo samples. I tried the developer's forum. Nobody's been on there in a while. I'm back to inserting printf statements. I'm out of love, frustrated and angry that the fate of a beautiful chip like the Propeller is in the hands of cowboys who think leaping in to reverse engineer a microwave oven is a natural way to eat breakfast. I don't find riddles and headaches fun any more. If I want to study the details, I'll come back when I have nothing better to do, but in the meantime I want results. Today. Anybody who'd recommend the Propeller for a beginner class deserves what the students will do to him.
Comments
Nope, There's been a NTSC/PAL library for Arduino for a while Google "TVOut" "Arduino" ... that said it's pretty crude compared to the Prop TV drivers
cheers ... BBR
Most VGA is very limited, mostly because of the smaller internal RAM.
"The project began in Ivrea, Italy in 2005 to make a device for controlling student-built interaction design projects less expensively than other prototyping systems available at the time."
The Arduino is a complete system/eco-system whereas the Prop is basically a chip.
In re-thinking it, I'm sure the biggest obstacles to active interest/adoption of the Prop are:
A) Lack of common programming language*, ie Basic, C, C++ which requires an unknown language called Spin. I think this is overlooked by many as a mere trifle.
I don't think people stop and think about what going the proprietary route means. A decision must be made by the instructor as to whether or not he/she wants to expend x amount of time learning a new language. Teachers are busy/lazy as anyone else, and expecting them to learn a new language to teach a course versus using what they probably already know (Sketch/Processing) is not what I would be willing to bet my paycheck on. Add to that the very real fear that they would look too novice like to the students they are teaching, and.....
*Yes, I know other languages are available, however its not really far to use as an example as its not what is Officially spec'd by Parallax, and not really known outside of the forum I think.
I wonder if the one, best thing Parallax could do to increase interest and adoption of Prop would be to draft in the Arduino wake.
Just hire or contract someone to get Processing and Wiring ported to support the Props. Or, fund some of the OSS dev's?
Does anyone not think the Prop would be far more attractive to instructors, students, and the Arduino masses if it used a similar language and environment? Assuming it is technically possible.
Imagine if it was magically made available, if just 10% of Arduino users took the now very small baby step over to the Wiring/Processing Prop? And imagine if every year, as new Uni students come in that additional 10% reoccured, and then 10-20% second/third year students needing more power picked up on this Prop-thing.....
It seems like this is happening in part already organically with the Prop ASC and other efforts. I think Parallax could make this happen at warp speed if they put some resources behind it.
It would only make uptake of the Prop/Prop II that much easier from a Buy-in decision as less expended time, familiarity, etc, and more successful to the existing Prop community and Parallax as a company.
Hopefully no one takes offense at my comments, as I think the Prop's are beyond cool. I just see a number of obstacles to real adoption that could be ameliorated.
John Abshier
As you work through the labs and assignments with the Arduino, do the same labs and assignments with the Prop.
I think analog input might be the only thing that the Arduino platform has over the Prop chip in terms of hardware capabilities. Get an MCP320x chip and use the excellent drivers at obex.parallax.com.
Once the professors see how easy and powerful the Prop chip is, maybe in the future they will consider introducing it in the curriculum! Better yet, they'll have your documentation via lab/assignments for the Prop chip as a reference.
You probably won't get to use the Prop officially for your assignments, but you'll learn a great deal, and probably come away with the conclusion that the Prop makes a lot of the tasks of schoolwork assignments TRIVIAL! (yeah, I said it, trivial). Of course, the non-trivial stuff comes from your actual application logic and you'll have much more fun developing that portion than fighting with the deficiencies of antiquated microcontrollers (yeah, I said it, AVR, PICs... antiquated compared to the Prop. Okay, maybe if you're producing hundreds of thousands of a particular product you might be better using the cheapest PIC possible, but how can that be fun? ... or if you really need to just do something very very simple then one of the many of hundreds of low cost PICs might fit your need).
As for the PIC comparisons, I'm actually glad that we studied the PIC in college, as it has helped me to understand the old way of doing things: setting up registers, banging your head against the documentation (even supplementary material) to understand all the various modes of the CCP module, messing with interrupts, etc ...
Yes PICs are good, so are AVRs. SXes were great because they were faster than PICs. But the peer-to-peer culture behind a product is where the average learner develops their product loyalty and preferences. Unlike most big companies (e.g.; Microchip and Atmel), Parallax has always been devoted to peer-to-peer support for the newcomer.
I repeat, Parallax's success in the educational market place has always been about their support and in particular their publications. Admittedly, they have tended to ignore C. But that has been because the C compilers that were any good were quite expensive and beyond the reach of the student population until recently.
And there are real questions of the need for C in a micro-controller setting (study the history of C and you see that it has based its success on cross-platform portability of programs for traditional mainframe computers. The idea was the you didn't have to buy software from the same company that sold the hardware. You could port existing software to different hardware as your company evolved.)
It isn't true that Arduino is the 'defacto-standard' of the education environment. Arduino has come into its own only because inexpensive and free C compilers for AVRs became available. But it does seem a rather odd and lop-side educational environment that promotes developers as 'artists' rather than competent programmers and engineers.
Prior to Arduino, Parallax pretty much has been the 'defacto-standard' and pace-setter of the educational micro-controllers. But with success, you eventually get attention. And that means competition that apes your key features of success - such as free compilers and fundamental publications. The big companies decided to finally provide free or cheap C as they couldn't sell the stuff for thousands of US dollars that they wanted to. New customers were just not appearing as they were ignoring the educational institutions and student populations.
So please, don't slam Parallax on its home turf. It has been quite generous and hard-working in providing value to students -- long before Arduino. And regardless of what Microchip or Arduino do, I suspect that it will respond well to its customers needs rather than merely try to ape the competition. Texas Instruments is the latest newcomer in this arena. I wonder how Arduino will hold up against Texas Instruments if their prices are undercut? Everybody loves a freebie.
Interesting comment about the "'latte' effects". I'm not sure that's a bad thing though. As far as I can tell the Arduino concept is targeted at non-engineer types. Rather like the target market for Apple computers verses the IBM PC. The former let's non-techies get on with stuff, the latter enabled techies to hack easily.
C compilers, or indeed any compilers, used to be expensive. Then along came Richard Stallman, his philosophy on free software and his GNU C compiler. Those who wanted to use AVRs targted GCC at the AVR and lo it became possible to make the Arduino.
Whilst C was about the first language the enabled cross platform portability it for sure was not targeted at mainframes. Indeed C and it's accompanying operating system Unix were designed to be small compared to what was being planned at the time (See Multics). It was to be used on mini-computers with not much more resources than a modern day micro-controller. The PDP-7 had an 18-bit word length, and its standard main memory was 4K words (equivalent to nine kilobytes) but upgradeable to 64K words (144 KB).
Again we can thank Richard Stallman and the GNU crew for that:)
http://mbed.org/
It uses a similar approach to programming, making it very simple, except that the compiler is accessed via the web. It works very well, and is even easier than the Ardiuno to use. NXP is giving them away to entrants to the Design Challenge competition! I got mine yesterday, but NXP had already given me one for running the LPC2000 group. I'm going to the Embedded Live show in London next week - ARM and NXP have stands, and I wouldn't be surprised if I get another one.
It is getting very popular.
It is interesting that these people don't consider themselves engineers and yet are quite fixed on C as a programing language choice. C/C++ demands more effort than SPIN, a steeper learning curve.
I have been going over Andre LaMothe' Hydra Manual - Chapter 15 and that is a very good introduction and overview of SPIN. Some things I had not noticed or forgotten stuck out. In fact, I think this presentation is much better than the Propeller Manual for an initial entry point, not so dense with details.
The foremost is that programmers in general use about 10-15% of a language. I suspect that this has strongly determined Parallax's approach to constructing programing languages. All the abstractions of C and higher Object Oriented Languages are pretty much left out. I suspect Arduino fans want a 'warts and all' formal programing language, rather than something less. A lot of academics are likely to prefer to teach such as there is more course content as well.
And like the BasicStamp, the Propeller doesn't get into data structures. Rather than have a full set of features for manipulating data, it is quite simple - pretty much one-dimensional arrays. This is certainly a philosophical influence. You can have that stuff if you want it, but you have to build it.
And another philosophic generality is akin to Dr. Dobb's Journal motto - "Running light on over byte". The Propeller is frugal in RAM and ROM while lightning fast in speed. It is an 'clean slate' that must be filled in by imagination and sweat rather than a system of hardware that just requires one to get their ducks in a row.
The new C3 board offers more of the 'ducks in a row' feel that Arduinio-nauts prefer. But it still offers the 'clean slate' of the Propeller when that is required.
As I've said before, these kinds of debates are endless. Mostly it is about one's perception of value. And as of yet, I just haven't found books and documentation that I enjoy for the Arduino.
I have never bothered to look at the Arduino before because, well, it's an AVR, been there, done that. It's programmed in C/C++ , been there, done that. What's the big deal?
But since finding out that we can possibly run Arduino style "sketches" on the Prop via Zog and since we now have the Prop A.S.C. board I started to sniff around at what Arduino really is. I have to say I'm impressed with the simplicity they have come up with as an introduction to the world of embedded control and micro-controllers.
Firstly "these people [that] don't consider themselves engineers", i.e. Arduino users, are not fixated on C/C++. That just happens to be what the Arduino developers have provided.
Normally true. But that is the point of the Arduino world. Arduino users have been exposed to a subset of C/C++ such that they don't get overwhelmed by detail when starting out. When writing your first Arduino "sketches" you don't have to know about "#include blabla.h" or "int main (int argc, char* argv[])". No you just write simple code that has immediately obvious meaning and it works. The Arduino documentation that I have seen only scratches the surface of C++, everything is kept as simple as possible for the beginner. More on this later.
I suspect that those new to programming and new to micro-controllers and whose primary aim not programming but to get some creation working don't care a hoot about "formal programming languages".
Now, imagine you have never picked up a micro-controller before and you have never programmed anything. You have some vague idea what it's about so you find out you can by an Arduino or a Propeller board to play with. Or maybe someone you know, or your school is about to teach you your first steps.
A simple first task might be to read the state of a pin and get it printed on your PC's screen.
The Propeller beginner will be confronted with this:
CON _clkmode = xtal1 + pll16x _xinfreq = 5_000_000 OBJ serial : "FullDuplexSerialPlus" PUB start | sensorValue serial.start(31 ,30, 0, 9600) repeat sensorValue := ina[2] console.dec(sensorValue) console.tx(13)An Arduino begineer will see this:void setup() { Serial.begin(9600); pinMode(2, INPUT); } void loop() { int sensorValue = digitalRead(2); Serial.println(sensorValue, DEC); }Quite frankly despite the fact that C++ is a vast and complicated language the Arduino beginner gets started with a lot less strange and confusing stuff than the Propeller beginner. Bingo he's hooked.That, I recently discovered, is the simple genius behind the Arduino.
I haven't really learned C/C++ and that immediately seems counter-intuitive to me. After all the everyday means is 'invalid' or 'empty'.
It took a lot for me to grasp "main()" in Visual Basic as well.
At some point it seems any computer language demands that we accept that 'this is what we do to make that work' and just try not to look too closely as what the words are supposed to me. Later, you will understand it.
I must say that it is a tribute to the Propeller that you can port Arduino code over to it.
Programing in C/C++ has cache, prestige value. It is something like this. If you care a Calculus text with you everywhere you go, people will comment that you are quite intelligent. But you don't have to read the book to gain the recognition.
One can argue that the separate sections in SPIN actually clarify rather than complicate is being done. Reams have been written of the obscurity of C code. Nonetheless, you do indeed demonstrate that once we master and fully understand something - regardless of how complex - it is crystal clear to ourselves.
Things are even easier with the mbed than with the Arduino:
#include "mbed.h" DigitalOut myled(LED1); int main() { while(1) { myled = 1; wait(0.2); myled = 0; wait(0.2); } }is all that is required to flash LED1 on the mbed, with a 0.2 second delay.
You might also have asked "what on earth are those empty pairs of brackets "()" hanging around for? And what's with the semi-colons?
Point taken and you are right, pretty much all languages have junk that makes them work. Even human languages. Not sure what we can do about it, turns out that if you take the junk away the language becomes too limited to express anything non-trivial.
But both the Prop and Arduino have done a good job of making the baby steps less painful.
Yes, well, errr... That is still yet to be demonstrated. I'm sure it will workout for simple stuff, we shall see how far we can push it.
By the way, I have today learned that a certain
However, it's hard to get the Arduinos in SE Asia. I cannot find any distributors who ever sold these at all, while many of my students are trying to reach them.
http://uk.farnell.com/jsp/search/productListing.jsp?SKUS=1813412,1813413,1813414&isRedirect=true
They will be cheaper elsewhere, especially if you get clones.
Thanks. I would order a clone and test them first. Right now I'm a bit busy with the Propellers, but if I have some more time, I'll definitely give them a try.
Nevertheless, if you want to use another platform - feel free to go and do so. I'll stick with the prop (and a little SX/B).
I know - the stamps are a nifty stuff.
Again, in my place where I'm staying, the Basic Stamps are very, very expensive. My students could only reach Arduino for now.
I hope starting microcontrollers is a cheap and inexpensive hobby though. :smilewinkgrin:
One thing that teaching English and studying Chinese since 1994 has done has to pretty much teach me how any linguistic argument turns the mind to mush. I got involved with Parallax and a BasicStamp because I wanted to compare my everyday linguistic knowledge with that of computer languages (possibly a big mistake). It has been very interesting, but after years of effort.... simply inconclusive.
Like Chinese versus English, C has its oddities and so does SPIN, but I would have to say that SPIN is not so philosophically committed to its own sophistication. (I hope that makes sense to others.) My main point was that Andre LaMothe's introductory overview of SPIN is a lot easier to read and understand why SPIN is the way it is. The Propeller Manual had to present all and everything, so it doesn't have that kind of presentation.
Void is indeed a 'type'. And C has many types that must be declared, along with a lot of other conceptual burden. SPIN tries to run on as little as possible of these types of things (it doesn't even have Strings).
There are good reasons for types in large programs. Void as a type seems to be an afterthought (Okay, I lied about never studying C). But since 'the devil is in the details' and C requires more details - it would seem to have more deviltry about it.
My biggest problem is that everyone that writes about programming feels the book has to be 700 pages or nobody will buy it. From my own experience, I have found I do far better if I can locate a good 150 page text to grasp the turf before I buy the 'doorstop'. And the next best thing is to have a Forum like this to ask why I am not comprehending the 700 page tome.
At some point, all computer languages must be grounded in hardware to have usefulness.
No, not so, "The C Programming Language" (K&R) by Brian Kernighan and Dennis Ritchie is the way I learned C back in 1984 or so. I only had MSDOS to run it on. It was many years later that I even saw my first UNIX system and certainly had not read any books about Unix programming.
But the main point is that the text heavily relies on stdio.h, which I never fully understood without the second text. I suppose in a classroom setting the gaps are filled in by lecture and peer-to-peer support. But studying independently, having both texts really help.
And of course, the UNIX text explains quite a bit that Linux just presumes you picked up (but may never have).
The hard part was that it seemed to me that early C compilers were not very fussy about what you asked them to compile. Any old gibberish that you typed in would get compiled, without much in the way of warning or error messages, to something which inevitably crashed. Perhaps it was just the compiler I had, can't remember what it was now, but later C standardization seems to have straightened out a lot of that.
What was so hard about stdio?
Mind you, at the time a whole second book dedicated to printf might have been helpful:)
The strengths and weaknesses of the Basic Stamp 2 are well known, and I really like it. For my robot the 4000 operations per second is plenty fast enough, and there are so many examples available that I can cut and paste impressive stuff together in a few hours. I'll probably keep using it for this reason alone.
The Arduino's main strengths are C++, speed, a built in A/D converter, and C++. It's major weakness is that not all its pins are symmetric, and the RAM doesn't go as far as you would think. For example using a serial motor controller and a serial LCD at the same time is a challenge. But never discount the C++ advantage as many algorithms are available in it.
The Propeller's multi-core architecture is pretty darn nifty and I'm glad I gave it a try. It's like having access to a threads package and makes true concurrent programming possible. So I have one cog ramping six servos, another doing the inverse kinematic floating point, and a third orchestrating things. RAM seems plenty spacious, Spin is fast enough for my robot arm, and it has functions with parameters and local variables. I'd need a floating point co-processor and servo controller to do that with the Basic Stamp 2 or Arduino. The down side is that Spin is a bit odd, I can deal, but it means re-coding things like an inverse kinematic transform which I found C++.
You might want to look at the quickstart and Catalina and sphinx and propforth, etc.
As far as over kill, I would not agree, should the cost be similar, which they now are, I would opt for too much to start with and allow greater flexibility for expansion later.