Ken, in the respect of helping Parallax as much as possible. It's it better for the bottom line if we buy chips directly from you, or is it all the same if we order from DigiKey?
Ken, in the respect of helping Parallax as much as possible. It's it better for the bottom line if we buy chips directly from you, or is it all the same if we order from DigiKey?
Thanks for asking, Martin.
Buying from Digi-Key or Mouser helps Parallax from a long-term perspective. It establishes interest from the distributors to promote the chip in their technical marketing efforts. And it compliments the plans we are making with these companies for distribution.
Mouser is also a place to find those hard-to-find parts, so it's a great store that you can buy Parallax products from.
I have been a customer of Mouser for a while.
Just like what Ken said, you can buy from Mouser or Digikey - as well as buying the Propeller, you can just buy the needed parts as well.
And, as Ken mentioned: It's a good way to promote the hardware through the store - it really help establishing your client base.
Ken, thanks for chiming in. It has been a very hot topic here as you have seen. It's a real pleasure for Parallax to regard "us all" as Parallax. I hope to return the favour on my part by ultimately using the prop commercially. However, I will still build for the hobbyist as that is my hobby
"damagedcells" gave us the best answer...
Within 24 hours and 3 tutorials I was able to reto-fit a OBJ and make a working PIR Intruder alarm with PST terminal messaging.
I have also written a 11 line program (a hack of the propeller help tutorials), which would (IMO) take probably a hundred lines (and a heck-of-alot of math) if you tried the same thing withoutr independent cogs operating in parallel.
BTW: Did we welcome you to the fantastic prop forum??? If not, welcome
I noticed your comments about Spin. I use a mix of Spin and Pasm. I am more at home with pasm. Spin is quite easy except for the hieroglyphics. Beginners shouldn't use statements like
x |< pin and such (instead of x := 1 << pin ) because they are harder to understand by many (including me). However, you should realise the former is likely quicker. And the way the prop works, while Spin is slower, often it does not matter because the timing complexities are in other cogs.
Those forum statistics are great !! Thanks guys for digging into this.
<rant> Unfortunately there is too much negativity from some regarding how the prop does not compare with other microcontrollers. For heaven's sake, a prop cannot do what my Celeron can do - this attitude by some is just plain ignorant. And it soon follows into diversion of the thread into an X--- debate. </rant>
Every microcontroller has it's own area of expertise.
I just want to take a moment and express my thoughts on how Ken chooses to handle Parallax business. I like open companies, mostly because I can trust them, or at the least have some firm grasp of what I'm dealing with overall. I also like them because there generally is some community surrounding them, and where that's true, there also is generally some synergy between the company, it's community, and me.
In this case, it just makes the hobby fun and productive. I enjoy the goings on, and having met many at Parallax personally, enjoy the quality of people this particular dynamic tends to attract. I stepped away from this stuff right after high school. At that time, I was banging on 8 bit computers (6502, 6809 -->Which is the most beautiful and potent 8 bit chip ever made), interfacing to things with the game controller ports, and just starting down this road in general. Lots of reasons for that, most just some artifact of where I was in life at the time. I'm back into this, and having a great time, my only complaint being time itself to do it, because of Parallax in general, and the highly differentiated Propeller.
This community brings a "you can do it" attitude that I find compelling, and often entertaining even when the occasional "biting" does occur. (I'm liberal in this, and very forgiving --life is easy that way) Parallax is friendly, capable, and the spirit of doing stuff is just catchy. On a hobby level, and I would argue small time pro level, that stuff is worth a lot. Thanks for it.
How can that be? There's a crying need for help over there...if you've got the expertise to share.
Perhaps it's not so much that people have more problems here but that you have more answers here.
I am actually one of the more active members of the XMOS forum. Members are awarded points for various activities, such as making posts and starting projects, and get a prize (an XK-1 kit worth $99) when they amass 512 points. I was one of the first members to get 512 points.
I am actually one of the more active members of the XMOS forum. Members are awarded points for various activities, such as making posts and starting projects, and get a prize (an XK-1 kit worth $99) when they amass 512 points. I was one of the first members to get 512 points.
They ought to award points for finishing projects. With X, the points would go unclaimed.
I've enjoyed this thread. Damagedcells is talented. It seems the whole active community bunched up on this one. I love the Propeller and I love this forum. I especially like the character that comes across whenever I read posts from Leon. I was grinning at the screen. Even though he at times appears blustery it's obvious he enjoys this forum and he has always helped me. The first time he responded to one of my questions I had to step back and ask, "Is it something I said?"
OK, now that I've admitted that I'm a big Leon fan...I will go back and read the parts that I skipped over. This forum is like my daily newspaper.
My quick 2 cents: For me, well supported TV and VGA output was the main selling point. I didn't see any other microcontroller that could do it and so the choice was Propeller or FPGA. Today, I'm still glad I picked Propeller because it's kinda like a Swiss Army knife or 10-in-1 screwdriver because you can use it for almost any app you can think of.
There are some things I'm missing though: MP3 decode, JPG decode, RTC, wireless, USB, more I/O pins
I think Prop2 will address most of these, so I'm staying put.
What evidence do you have that interrupt-driven applications are unreliable? Your mobile phone almost certainly uses an ARM chip, and the software is interrupt-driven - when did that last crash on you?
I have never found devices named "smart phones" to be 'smart' or reliable as phones. When looking at the calendar, if a call comes in, stops working; nokia 6682. Inhereted iphone (due to purchaser's upgrade to iphone2), doing some sequence of actions when a call came in required weird hardware reset. (Solution, turn off everything and don't anything complex). Smart phone appear to 'hide' errors well by crashing silently and recovering silently so they apear to be only slow, not crashed. Although I do see full power cycles on occasion. In any case, while this is fine for most users, I do not fine this acceptable in anything I do or use.
If you define "reliable" as "predicable and repeateable" then W95 is reliable, you know it is going to crash after x time or y operations.
The future of Parallax will continue on. The future of the Prop1 will die when Prop2 comes out. As the Prop stands now it isn't going find it's place in the Shuttle, or in MRIs, or in any high end CNCs. The 8 cogs sounds great but without internal ADC it is limited to Blinky lights and running RC servos. I have been working with this Prop for a long time now and can not get external ADCs to work right. I purchased an Adrino Mega 2650 with 16 internal ADCs and had my project working in 10 minutes.
I suspect that 80% of the newbes that buy the Prop get frustrated after a month and it ends up in a desk drawer. Lack of good tutorials and videos is a major disappointment to a beginner. I would like to see some real completed worthwhile Projects posted with circuits and code.
I must respectfully disagree. While it is true that there could be better documentation, there is still enough to complete some very serious projects. I do not know just exactly what high end CNC has to do with it, because that is just price. I am almost done with a very complicated piece of CNC equipment, and I am very satisfied with the Propeller and it's abilities. I will be more than happy to show you photos and video of it in action in just a few days.
It operates with both analog and digital signals. As for sharing code and circuitry, a few days ago, it was made obvious to me that my contributions were unappreciated, so I no longer provide that service freely. However, if someone specifically needed help, I would help them with both code and circuits.
The future of the Prop1 will die when Prop2 comes out.
Not at all. If nothing else the Prop II will never come in a DIP package so the Prop I will still have a place for prototypes and as a learning vehicle for beginners in electronics, and micro-controllers. Not to mention all the places where a DIP is idea for the quick hack.
On top of that the Prop II will not be as low power as the Prop I.
Besides Parallax have promised to keep it around for a long time.
Lack of good tutorials and videos is a major disappointment to a beginner.
Perhaps but the Prop manual was all I needed to lash up my first DIP Prop chip to a serial port and get the first programming steps under my belt. I guess videos are useful but I never felt the need.
I suspect that 80% of the newbes that buy the Prop get frustrated after a month and it ends up in a desk drawer.
Having watched people come and go on this forum for a long while I get the opposite view. The newcomers soon get enamored by the Prop and enthuse about how easy it was to get there projects off the ground.
without internal ADC it is limited to Blinky lights and running RC servos. I have been working with this Prop for a long time now and can not get external ADCs to work right. I purchased an Adrino Mega 2650 with 16 internal ADCs and had my project working in 10 minutes. .
How on earth does the lack of an internal ADC limit the propeller to those actives given what people are doing with it?. External ADC chips are extremely common and can be better than those found in microcontrollers, the fact you could not get it to work is not something that can be blamed on the propeller. It might have been worth you posting your problems on this very forum.
As for the Arduino? It is convenient and great for some but performance wise it is not a patch on the propeller as far as I can see and I suspect will also never be found in a shuttle.
I think we should listen closely to garylake's comments. If you look at his previous posts you'll see that he had trouble integrating to a keyboard MIDI interface, and working with an ADC input. He was able to resolve the MIDI problem, but could not resolve the ADC issue. I'm sure the ADC issue could have been resolved as well with more input form others on the forum. I think the issue he is raising is that other processors may have more documentation to guide a novice user.
I wouldn't have any problems with it, but I can see why a beginner might not be able to get it to work. It needs better documentation.
Here is the code:
'' =================================================================================================
''
'' File....... jm_adc0834_ez_demo.spin
'' Purpose....
'' Author..... Jon McPhalen
'' Copyright (c) 2009 Jon McPhalen
'' -- see below for terms of use
'' E-mail..... jon@jonmcphalen.com
'' Started....
'' Updated.... 01 JUL 2009
''
'' =================================================================================================
con
_clkmode = xtal1 + pll16x
_xinfreq = 5_000_000
US_005 = 80_000_000 / 1_000_000 * 5 ' 5us '
con
#0, CLS, HOME, #8, BKSP, TAB, LF, CLREOL, CLRDN, CR ' PST formmatting control
obj
adc : "jm_adc0834_ez"
pst : "fullduplexserial" ' use Parallax Serial Terminal
pub main | ch, analog
adc.init(0, 1, 2) ' setup ADC
pst.start(31, 30, %0000, 115_200) ' start terminal
pst.tx(CLS)
pst.str(string("ADC0834 Demo"))
repeat
pst.tx(HOME)
pst.tx(LF)
pst.tx(LF)
repeat ch from 0 to 3
pst.dec(ch)
pst.str(string(": "))
analog := adc.read(ch) ' read raw, 0-255
pst.dec(analog)
pst.tx(CLREOL)
pst.tx(TAB)
analog := adc.scale(analog, 750, 2250) ' scale to 750-2250
pst.dec(analog)
pst.tx(CLREOL)
pst.tx(CR)
pst.tx(CLRDN) ' terminal clean-up
waitcnt(clkfreq / 10 + cnt)
dat
{{
Copyright (c) 2009 Jon McPhalen
Permission is hereby granted, free of charge, to any person obtaining a copy of this
software and associated documentation files (the "Software"), to deal in the Software
without restriction, including without limitation the rights to use, copy, modify,
merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice shall be included in all copies
or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
}}
This what some Arduino code for the ADC looks like:
/*
Analog input, analog output, serial output
Reads an analog input pin, maps the result to a range from 0 to 255
and uses the result to set the pulsewidth modulation (PWM) of an output pin.
Also prints the results to the serial monitor.
The circuit:
* potentiometer connected to analog pin 0.
Center pin of the potentiometer goes to the analog pin.
side pins of the potentiometer go to +5V and ground
* LED connected from digital pin 9 to ground
created 29 Dec. 2008
Modified 4 Sep 2010
by Tom Igoe
This example code is in the public domain.
*/
// These constants won't change. They're used to give names
// to the pins used:
const int analogInPin = A0; // Analog input pin that the potentiometer is attached to
const int analogOutPin = 9; // Analog output pin that the LED is attached to
int sensorValue = 0; // value read from the pot
int outputValue = 0; // value output to the PWM (analog out)
void setup() {
// initialize serial communications at 9600 bps:
Serial.begin(9600);
}
void loop() {
// read the analog in value:
sensorValue = analogRead(analogInPin);
// map it to the range of the analog out:
outputValue = map(sensorValue, 0, 1023, 0, 255);
// change the analog out value:
analogWrite(analogOutPin, outputValue);
// print the results to the serial monitor:
Serial.print("sensor = " );
Serial.print(sensorValue);
Serial.print("\t output = ");
Serial.println(outputValue);
// wait 10 milliseconds before the next loop
// for the analog-to-digital converter to settle
// after the last reading:
delay(10);
}
It's using the internal ADC of the AVR, of course. It's documented very well, with exact details of how to hook up a pot to the ADC input.
The lack of a dedicated ADC does not bother me either. There are so many kinds of ADCs fit for specific purposes. For example, 18 bits differential for a bridge sensor. I would hardly want that integrated on the chip along with the digital circuitry, and I might want it located right next to the signal source. That is just one kind of specialty ADC. Occasionally the built-in sigma-delta with a few external components is exactly right. I hover on the border between science an technology and specialty ADCs are more often the rule than the exception.
I consider the Prop great for small scientific instruments. It has all the timing, i/o, user interface capabilities, data storage, etc etc. that typically come up in a small self-contained instrument, and the flexibility to be easily tailored for relatively short runs. I appreciate the symmetry of the pins, that allows for quick board layout. Need to stick in an XBee in a particular spot on a board? Just shift existing functions over a few pins to make room, declare a serial port, and there you have it!
The people I work with are mostly in "soft" sciences like biology and consider me a technologist, but I am not at all sophisticated in different micro-processors, compilers, tool chains, programming esoterica etc. I would rather have one sharp Swiss army knife than a chest full of cutlery and food processors. I am coming at this from the background of the BASIC Stamp for my OWL2pe data loggers and other projects, but have been pushing that to its limits. I have used well over 1000 Stamps in the past few months; gradually transitioning to Propeller. I will probably stick with the Prop I for a long time as it will be quite adequate, and I need the low quiescent power. Finally, and probably foremost, Parallax is a great company to do business with, including ithese forums that are indicative of their attitude.
I think we should listen closely to garylake's comments. ..........................................I think the issue he is raising is that other processors may have more documentation to guide a novice user.
I can see how you come to that conclusion based on some further research but his post here did not make that idea clear. Of course the Arduino has built in ADC so analogue in is trivial but what if you want to connect a mouse or do any number of other things, then you are back using other peoples code and the microcontroller manufacturer has little control over that.
There was talk of providing some guidelines for objects posted to the OBEX, one aspect is documentation but then again, any code can be better than no code.
I am glad to hear that parallax are producing some gold-plated objects. One of my earliest posts on the forums complained about the lack of comments ect in the Parallax made objects, it slowed my progress with the TV out etc.
The forum can and will fill many other gaps, I think it is always worth emailing the object creator if you have a problem, even just to point him/her at a forum post on the subject.
Yeah. On top of that, sure Propeller II may be munching a bit more on power, but there are two things trading that nasty stuff off for the best: It will be mucho powerful than Propeller 1 and it runs off 1.8 V (not a big deal, you can actually use the switchmode LDO to reduce that kind of consumption). I can actually understand why it really eat powers - it's largely because of smaller transistor geometry - transistor starts to leak like a sieve when it get shrunken.
Propeller 1 will still be useful for a long time (I can agree with that!) where a quick slap-and-hack is needed, such as DIP-40 for the wire-wrapping quickie. If the Propeller II is to be made on, strictly, a DIP board, I can imagine that it would kind of look like a Motorola DIP-64 68k CPU.
That 68k surprised me - I never have seen a DIP chip that HUGE... (I was used to be seeing the package from a cheap jellybean DIP-8 upward to a DIP-40 system controller on ancient Pentium motherboards - 'til I got the Apple IIG motherboard...)
And, there are so much to do with Propeller 1 chips - like I said, there are so much headrooms in the COG's Integer Unit architectures, so just enjoy your favorite DIP-40 Propeller 1 chips for many years to come!
I advise you not to give up on the Prop so quickly. After you become better acquainted with the Prop, I am certain that you will enjoy it's many feautres. Don't leave just yet!
I hope the Prop and Parallax continue to have success and prosper, I am a big fan!
I have built a few commercial products for various clients based upon the Propeller, and they are all working well. I will continue to use the Prop as my first choice as an embedded controller. Things have been a bit slow in the industries I work in, but starting to pick up. But my volume for these products is in the dozens per year, nothing huge. Niche applications in automated welding and recycling industries. But ya never know!
The propeller and in particular the Parallax USB prop proto board have proven to be very reliable in industrial environments controlling arc welding equipment. The cog approach is ideal for the way I handle tasks, as well as being easy enough for this old brain.
... The cog approach is ideal for the way I handle tasks, as well as being easy enough for this old brain.
Dave, I think you may just have hit on the key to this whole issue!
The Propeller is just too darn easy to use. Naturally it has no sex appeal to younger engineers when even their old ossified bosses (people like me!) can readily understand what they're doing, and how their proposed solutions are going to work.
These poor young engineers would lose all their excuses for overrunning project schedules and blowing budgets, and also their main reason for insisting on buying all that fancy new software or test equipment - which is naturally required to solve all the many complex problems that inevitably arise with other microcontrollers.
How could these young engineers face their friends - all of whom are undoubtedly left wretched and bedraggled at the end of each day after tackling the difficulties in programming ARM, or NXP or X___ processors? How can they cheerfully say "Oh yes, I finished my deteministic multiprocessing real-time controller application this morning!" when their friends have taken months in a futile attempt to achieve the same thing? The reaction of their friends would undoubtedly be a contemptuous "Oh sure, but you used a Propeller. I'll respect you when you can do that on an XYZ processor!"
It's no wonder the Prop I has little traction in industrial applications. But once you have identified the problem correctly, the solution is of course obvious - the Prop II must immediately be made so complex that only a few rarefied individuals will be able to even read the technical specs - let alone program one!
Comments
Thanks for asking, Martin.
Buying from Digi-Key or Mouser helps Parallax from a long-term perspective. It establishes interest from the distributors to promote the chip in their technical marketing efforts. And it compliments the plans we are making with these companies for distribution.
Ken Gracey
I have been a customer of Mouser for a while.
Just like what Ken said, you can buy from Mouser or Digikey - as well as buying the Propeller, you can just buy the needed parts as well.
And, as Ken mentioned: It's a good way to promote the hardware through the store - it really help establishing your client base.
"damagedcells" gave us the best answer...
BTW: Did we welcome you to the fantastic prop forum??? If not, welcome
I noticed your comments about Spin. I use a mix of Spin and Pasm. I am more at home with pasm. Spin is quite easy except for the hieroglyphics. Beginners shouldn't use statements like
x |< pin and such (instead of x := 1 << pin ) because they are harder to understand by many (including me). However, you should realise the former is likely quicker. And the way the prop works, while Spin is slower, often it does not matter because the timing complexities are in other cogs.
Those forum statistics are great !! Thanks guys for digging into this.
<rant> Unfortunately there is too much negativity from some regarding how the prop does not compare with other microcontrollers. For heaven's sake, a prop cannot do what my Celeron can do - this attitude by some is just plain ignorant. And it soon follows into diversion of the thread into an X--- debate. </rant>
Every microcontroller has it's own area of expertise.
How can that be? There's a crying need for help over there...if you've got the expertise to share.
Perhaps it's not so much that people have more problems here but that you have more answers here.
I just want to take a moment and express my thoughts on how Ken chooses to handle Parallax business. I like open companies, mostly because I can trust them, or at the least have some firm grasp of what I'm dealing with overall. I also like them because there generally is some community surrounding them, and where that's true, there also is generally some synergy between the company, it's community, and me.
In this case, it just makes the hobby fun and productive. I enjoy the goings on, and having met many at Parallax personally, enjoy the quality of people this particular dynamic tends to attract. I stepped away from this stuff right after high school. At that time, I was banging on 8 bit computers (6502, 6809 -->Which is the most beautiful and potent 8 bit chip ever made), interfacing to things with the game controller ports, and just starting down this road in general. Lots of reasons for that, most just some artifact of where I was in life at the time. I'm back into this, and having a great time, my only complaint being time itself to do it, because of Parallax in general, and the highly differentiated Propeller.
This community brings a "you can do it" attitude that I find compelling, and often entertaining even when the occasional "biting" does occur. (I'm liberal in this, and very forgiving --life is easy that way) Parallax is friendly, capable, and the spirit of doing stuff is just catchy. On a hobby level, and I would argue small time pro level, that stuff is worth a lot. Thanks for it.
I am actually one of the more active members of the XMOS forum. Members are awarded points for various activities, such as making posts and starting projects, and get a prize (an XK-1 kit worth $99) when they amass 512 points. I was one of the first members to get 512 points.
They ought to award points for finishing projects. With X, the points would go unclaimed.
OK, now that I've admitted that I'm a big Leon fan...I will go back and read the parts that I skipped over. This forum is like my daily newspaper.
I have to admit the same, having laughed out loud now and then when I read his posts.
There are some things I'm missing though: MP3 decode, JPG decode, RTC, wireless, USB, more I/O pins
I think Prop2 will address most of these, so I'm staying put.
So the answer is "NO"? [I.E "processor" = "core" & "processor" <> "thread"]?
edit - I'm catching up from page 5, and I cannot tell if this is an "apples to apples" comparison; if it is not, it is only noise to me.
I have never found devices named "smart phones" to be 'smart' or reliable as phones. When looking at the calendar, if a call comes in, stops working; nokia 6682. Inhereted iphone (due to purchaser's upgrade to iphone2), doing some sequence of actions when a call came in required weird hardware reset. (Solution, turn off everything and don't anything complex). Smart phone appear to 'hide' errors well by crashing silently and recovering silently so they apear to be only slow, not crashed. Although I do see full power cycles on occasion. In any case, while this is fine for most users, I do not fine this acceptable in anything I do or use.
If you define "reliable" as "predicable and repeateable" then W95 is reliable, you know it is going to crash after x time or y operations.
I suspect that 80% of the newbes that buy the Prop get frustrated after a month and it ends up in a desk drawer. Lack of good tutorials and videos is a major disappointment to a beginner. I would like to see some real completed worthwhile Projects posted with circuits and code.
I must respectfully disagree. While it is true that there could be better documentation, there is still enough to complete some very serious projects. I do not know just exactly what high end CNC has to do with it, because that is just price. I am almost done with a very complicated piece of CNC equipment, and I am very satisfied with the Propeller and it's abilities. I will be more than happy to show you photos and video of it in action in just a few days.
Bruce
That's great! Would love to see it in action. Does it work with analog or just digital?
But I bet you are willing to share you circuits and code.
It operates with both analog and digital signals. As for sharing code and circuitry, a few days ago, it was made obvious to me that my contributions were unappreciated, so I no longer provide that service freely. However, if someone specifically needed help, I would help them with both code and circuits.
Bruce
Not at all. If nothing else the Prop II will never come in a DIP package so the Prop I will still have a place for prototypes and as a learning vehicle for beginners in electronics, and micro-controllers. Not to mention all the places where a DIP is idea for the quick hack.
On top of that the Prop II will not be as low power as the Prop I.
Besides Parallax have promised to keep it around for a long time.
Perhaps but the Prop manual was all I needed to lash up my first DIP Prop chip to a serial port and get the first programming steps under my belt. I guess videos are useful but I never felt the need.
Having watched people come and go on this forum for a long while I get the opposite view. The newcomers soon get enamored by the Prop and enthuse about how easy it was to get there projects off the ground.
How on earth does the lack of an internal ADC limit the propeller to those actives given what people are doing with it?. External ADC chips are extremely common and can be better than those found in microcontrollers, the fact you could not get it to work is not something that can be blamed on the propeller. It might have been worth you posting your problems on this very forum.
As for the Arduino? It is convenient and great for some but performance wise it is not a patch on the propeller as far as I can see and I suspect will also never be found in a shuttle.
Graham
I found it here:
http://obex.parallax.com/objects/459/
I wouldn't have any problems with it, but I can see why a beginner might not be able to get it to work. It needs better documentation.
Here is the code:
'' ================================================================================================= '' '' File....... jm_adc0834_ez_demo.spin '' Purpose.... '' Author..... Jon McPhalen '' Copyright (c) 2009 Jon McPhalen '' -- see below for terms of use '' E-mail..... jon@jonmcphalen.com '' Started.... '' Updated.... 01 JUL 2009 '' '' ================================================================================================= con _clkmode = xtal1 + pll16x _xinfreq = 5_000_000 US_005 = 80_000_000 / 1_000_000 * 5 ' 5us ' con #0, CLS, HOME, #8, BKSP, TAB, LF, CLREOL, CLRDN, CR ' PST formmatting control obj adc : "jm_adc0834_ez" pst : "fullduplexserial" ' use Parallax Serial Terminal pub main | ch, analog adc.init(0, 1, 2) ' setup ADC pst.start(31, 30, %0000, 115_200) ' start terminal pst.tx(CLS) pst.str(string("ADC0834 Demo")) repeat pst.tx(HOME) pst.tx(LF) pst.tx(LF) repeat ch from 0 to 3 pst.dec(ch) pst.str(string(": ")) analog := adc.read(ch) ' read raw, 0-255 pst.dec(analog) pst.tx(CLREOL) pst.tx(TAB) analog := adc.scale(analog, 750, 2250) ' scale to 750-2250 pst.dec(analog) pst.tx(CLREOL) pst.tx(CR) pst.tx(CLRDN) ' terminal clean-up waitcnt(clkfreq / 10 + cnt) dat {{ Copyright (c) 2009 Jon McPhalen Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. }}This what some Arduino code for the ADC looks like:
/* Analog input, analog output, serial output Reads an analog input pin, maps the result to a range from 0 to 255 and uses the result to set the pulsewidth modulation (PWM) of an output pin. Also prints the results to the serial monitor. The circuit: * potentiometer connected to analog pin 0. Center pin of the potentiometer goes to the analog pin. side pins of the potentiometer go to +5V and ground * LED connected from digital pin 9 to ground created 29 Dec. 2008 Modified 4 Sep 2010 by Tom Igoe This example code is in the public domain. */ // These constants won't change. They're used to give names // to the pins used: const int analogInPin = A0; // Analog input pin that the potentiometer is attached to const int analogOutPin = 9; // Analog output pin that the LED is attached to int sensorValue = 0; // value read from the pot int outputValue = 0; // value output to the PWM (analog out) void setup() { // initialize serial communications at 9600 bps: Serial.begin(9600); } void loop() { // read the analog in value: sensorValue = analogRead(analogInPin); // map it to the range of the analog out: outputValue = map(sensorValue, 0, 1023, 0, 255); // change the analog out value: analogWrite(analogOutPin, outputValue); // print the results to the serial monitor: Serial.print("sensor = " ); Serial.print(sensorValue); Serial.print("\t output = "); Serial.println(outputValue); // wait 10 milliseconds before the next loop // for the analog-to-digital converter to settle // after the last reading: delay(10); }It's using the internal ADC of the AVR, of course. It's documented very well, with exact details of how to hook up a pot to the ADC input.
I consider the Prop great for small scientific instruments. It has all the timing, i/o, user interface capabilities, data storage, etc etc. that typically come up in a small self-contained instrument, and the flexibility to be easily tailored for relatively short runs. I appreciate the symmetry of the pins, that allows for quick board layout. Need to stick in an XBee in a particular spot on a board? Just shift existing functions over a few pins to make room, declare a serial port, and there you have it!
The people I work with are mostly in "soft" sciences like biology and consider me a technologist, but I am not at all sophisticated in different micro-processors, compilers, tool chains, programming esoterica etc. I would rather have one sharp Swiss army knife than a chest full of cutlery and food processors. I am coming at this from the background of the BASIC Stamp for my OWL2pe data loggers and other projects, but have been pushing that to its limits. I have used well over 1000 Stamps in the past few months; gradually transitioning to Propeller. I will probably stick with the Prop I for a long time as it will be quite adequate, and I need the low quiescent power. Finally, and probably foremost, Parallax is a great company to do business with, including ithese forums that are indicative of their attitude.
I can see how you come to that conclusion based on some further research but his post here did not make that idea clear. Of course the Arduino has built in ADC so analogue in is trivial but what if you want to connect a mouse or do any number of other things, then you are back using other peoples code and the microcontroller manufacturer has little control over that.
There was talk of providing some guidelines for objects posted to the OBEX, one aspect is documentation but then again, any code can be better than no code.
I am glad to hear that parallax are producing some gold-plated objects. One of my earliest posts on the forums complained about the lack of comments ect in the Parallax made objects, it slowed my progress with the TV out etc.
The forum can and will fill many other gaps, I think it is always worth emailing the object creator if you have a problem, even just to point him/her at a forum post on the subject.
Graham
If someone is having trouble, then we haven't put enough time in it yet...
I'll take that challenge.. I've got ADC (hopefully they've already shipped) chips on the way.
OBC
Propeller 1 will still be useful for a long time (I can agree with that!) where a quick slap-and-hack is needed, such as DIP-40 for the wire-wrapping quickie. If the Propeller II is to be made on, strictly, a DIP board, I can imagine that it would kind of look like a Motorola DIP-64 68k CPU.
That 68k surprised me - I never have seen a DIP chip that HUGE... (I was used to be seeing the package from a cheap jellybean DIP-8 upward to a DIP-40 system controller on ancient Pentium motherboards - 'til I got the Apple IIG motherboard...)
And, there are so much to do with Propeller 1 chips - like I said, there are so much headrooms in the COG's Integer Unit architectures, so just enjoy your favorite DIP-40 Propeller 1 chips for many years to come!
I advise you not to give up on the Prop so quickly. After you become better acquainted with the Prop, I am certain that you will enjoy it's many feautres. Don't leave just yet!
Bruce
I have built a few commercial products for various clients based upon the Propeller, and they are all working well. I will continue to use the Prop as my first choice as an embedded controller. Things have been a bit slow in the industries I work in, but starting to pick up. But my volume for these products is in the dozens per year, nothing huge. Niche applications in automated welding and recycling industries. But ya never know!
The propeller and in particular the Parallax USB prop proto board have proven to be very reliable in industrial environments controlling arc welding equipment. The cog approach is ideal for the way I handle tasks, as well as being easy enough for this old brain.
Good Stuff!
Dave KI4PSR
Dave, I think you may just have hit on the key to this whole issue!
The Propeller is just too darn easy to use. Naturally it has no sex appeal to younger engineers when even their old ossified bosses (people like me!) can readily understand what they're doing, and how their proposed solutions are going to work.
These poor young engineers would lose all their excuses for overrunning project schedules and blowing budgets, and also their main reason for insisting on buying all that fancy new software or test equipment - which is naturally required to solve all the many complex problems that inevitably arise with other microcontrollers.
How could these young engineers face their friends - all of whom are undoubtedly left wretched and bedraggled at the end of each day after tackling the difficulties in programming ARM, or NXP or X___ processors? How can they cheerfully say "Oh yes, I finished my deteministic multiprocessing real-time controller application this morning!" when their friends have taken months in a futile attempt to achieve the same thing? The reaction of their friends would undoubtedly be a contemptuous "Oh sure, but you used a Propeller. I'll respect you when you can do that on an XYZ processor!"
It's no wonder the Prop I has little traction in industrial applications. But once you have identified the problem correctly, the solution is of course obvious - the Prop II must immediately be made so complex that only a few rarefied individuals will be able to even read the technical specs - let alone program one!
I predict sales will soar!
Ross.