AVR complementing Propeller (Everyone contribute Please).
davidsaunders
Posts: 1,559
AVR complementing Propeller.
I have seen so many debates on the virtues of the Propeller vs. AVR on these forums, I am now going to flip this.
The purpose of this thread is for everyone to show how the Propeller complements the AVR, and how the AVR complements the Propeller.
The AVR and Propeller are two quite different micros, each with its own strengths and weaknesses. The AVR is good when you need timing by interrupt, a good low speed bit banger, etc.
I ask that every one contribute the positive nature of both, and how they can be used to complement each other. For my contribution see my AVR GG VGA thread in the Propeller forum (I know that it is a little extreme, though it is a way to bring these two onto common ground).
I have seen so many debates on the virtues of the Propeller vs. AVR on these forums, I am now going to flip this.
The purpose of this thread is for everyone to show how the Propeller complements the AVR, and how the AVR complements the Propeller.
The AVR and Propeller are two quite different micros, each with its own strengths and weaknesses. The AVR is good when you need timing by interrupt, a good low speed bit banger, etc.
I ask that every one contribute the positive nature of both, and how they can be used to complement each other. For my contribution see my AVR GG VGA thread in the Propeller forum (I know that it is a little extreme, though it is a way to bring these two onto common ground).
Comments
Here is a little sensor I/F and prototyping board I designed for someone using an AVR ATtiny45:
http://www.leonheller.com/ATtiny45%20Sensor%20Board/Interface.gif
I've just been testing one of the boards he sent me, in lieu of payment. It might make a useful peripheral, I could modify the board to provide an I2C interface connector.
I use an Atmel AVR Dragon for programming and debugging AVRs, the board has a six-way connector for one.
2. ADC.
For these reasons, AVRs could be considered as viable Prop peripherals. And they're certainly less expensive than dedicated ADCs. I would not classify interrupts as a plus, in comparing to a Prop, though. Interrupts are nothing more than a work-around for single-processor micros. People miss them in the Propeller only until they come up to speed with the architecture and realize they're not needed.
-Phil
-Phil
In general I agree with what you say, but there are times when having an interrupt is beneficial. Two uses that come to mind at the moment are for a watchdog timer and an interrupt for processing an infrequent but critical event. And yes I am aware that a cog can do this, but that ties up a cog or a substantial number of a cog's cycles.
Aren't some MCUs able to sleep in super low power mode until an interrupt event happens? SX chips? Maybe AVR ... I forget. Such a sleep mode is a definite plus if you're running on batteries. Having to use interrupts can be painful, but for many applications indeterminance (just one key factor) is not relevant.
Propeller can be battery powered too of course and will last a long time on 2AA's with the right kind of regulation, but it is relatively energy inefficient compared to some MCUs.
Hi jazzed,
I may be wrong on this (not being a hardware expert) but if the slow internal clock is in use, only one cog is currently running, and that cog is essentially doing a waitpeq, isn't it acting very much like a processor in low power mode waiting for an external interrupt?
Of course, I realize the Prop is not designed for ultra low power applications - but neither are most MCUs. The company I currently work in makes devices which are battery operated and expected to last for 5 or more years in the field - but this means we have to buy special low power versions of the chips we use which are more expensive than the normal versions.
Maybe a low powered prop would be a good thing once the Prop II is out?
Ross.
-Phil
Nice idea. You'd almost have to leave it up to the EEPROM to drain the battery in that state.
The Prop is certainly far more capable, and has the wonderful
precision timing and video services...but I have MUCH more
experience with AVR and ARM so it is a perfect match for me.
I especially enjoy using the Atmega1284p with a Prop. The 1284p
can hold an enormous C program in its 128kb of flash. It's just 5.00USD
and runs from 1.8 to 5.5V and is very stingy in some of its sleep modes.
It may be a while before I get to play with my uC's though. We have big trouble
brewing here :-( We are all carrying our weapons everywhere we go.
My time here on the forum may be limited or non-existent for a time :-(
Sorry to hear that, be safe.
C.W.
Heck, if response time is not critical you could turn the whole circuit on and off. Good for remote monitoring where readings are taken at low rates.
Sorry to hear you are having problems. Please be careful. You would be sorely missed on the forum.
I wonder if it is possible to have the Atmega emulate the eeprom and load the prop software. That would add flexibility and save a chip.
tII I hope things begin to improve where you are.
I find the intent of starting this thread a complete failure. The initial intent was to try to get people to agree on both of these micros in a non disputive manner. The opposite seems to have happened.
I'm not sure what your goal is, are trying to build a bridge between "fan clubs"?
It sounds like you have your work cut out for you on your VGA project, I would focus on that without worrying about all the silly Prop this, AVR that, I wanna be an Arduino stuff.
C.W.
Good call. I was hoping to shine a little light on the fact that one does not have to exclude the other. Though I do not that I even fully agree with my own point, I keep finding myself asking why can't I just do that in another core while doing the AVR side of my VGA project, only to wish that the AVR were a Prop.
I come to the forums both to learn and to relax, as for me a little bit of intellectual interaction is quite soothing to the soul.
I was feeling sorry for myself today, having to deal with soul-sucking Windows crash issues. Then I read your post and realized how how much worse things could be. Please be careful! And please report back from time to time, so we know you're okay!
-Phil
Stay safe. I know many of us enjoy your contributions here.
I don't really see this thread as a failure. At least two of us agree with you (Holly and I), and others seem to implicitly agree that the features available on other chips (interrupts, adc's, etc) are useful in conjunction with the prop. Unfortunately folks who disagree with you are far more likely to post a response than those who agree. Human nature......sigh.