Wow! Newbie experience...
bmb!
Posts: 26
I've messed around with basic stamps for years, mostly hobby but a couple work related projects. I've had a Propeller prototype board on the shelf for months finally got around to wiring it up. All I can say is Wow! Anyone debating making the jump from Basic stamps to Propeller chips, go for it!
With low expectations I plugged my PS/2 mouse and VGA LCD monitor into the board then loaded the hires VGA demo. After compiling and loading to RAM I was greeted with a beautiful VGA picture, responsive mouse cursor, and smooth scrolling. Had to do a sanity check and look at the one chip doing all this work.
Only negative, which is a plus after the learning curve, is learning the new language. Being an OOP developer I cursed using the Stamp's simplistic basic language. But on the flip side I knew my way around PBASIC but I did miss objects, functions, etc...
Anyway, awesome job Parallax and thanks for all the free tools/documentation!!! I'm very excited to start digging into some project using this chip, and anyone sitting on the fence about the Propeller go pick one up and give it a try!
With low expectations I plugged my PS/2 mouse and VGA LCD monitor into the board then loaded the hires VGA demo. After compiling and loading to RAM I was greeted with a beautiful VGA picture, responsive mouse cursor, and smooth scrolling. Had to do a sanity check and look at the one chip doing all this work.
Only negative, which is a plus after the learning curve, is learning the new language. Being an OOP developer I cursed using the Stamp's simplistic basic language. But on the flip side I knew my way around PBASIC but I did miss objects, functions, etc...
Anyway, awesome job Parallax and thanks for all the free tools/documentation!!! I'm very excited to start digging into some project using this chip, and anyone sitting on the fence about the Propeller go pick one up and give it a try!
Comments
Welcome to the forum.
Great to hear you got it all going so easily .. the Propeller is awesome.
And you will find many very helpfull people here .. so keep us posted how you go with it all.
cheers Melbourne Australia
Welcome to the forum, and I agree with you, anyone lurking these forums who haven't got a Propeller, GET ONE quick so you can join in the fun, it's a fantastic chip.
Baggers.
OBC
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New to the Propeller?
Getting started with the Protoboard? - Propeller Cookbook
Got an SD card? - PropDOS
A Living Propeller FAQ - The Propeller Wiki
(Got the Knowledge? Got a Moment? Add something today!)
Depending on what you want to do, the Propeller ProtoBoard and accessory kit will get you a long ways.
Check URL = www.parallax.com/Store/Microcontrollers/PropellerDevelopmentBoards/tabid/514/List/0/CategoryID/73/Level/a/Default.aspx?SortField=ProductName,ProductName for details.
In my case, this has been an excellent choice.
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Harley Shanko
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"A complex design is the sign of an inferior designer." - Jamie Hyneman, Myth Buster
DGSwaner
* almost. Add a 9volt battery to make things happen
Not including the fact that buying 20 of them has some further advantage
The ingredients come close to their true value...
What I want to say is: When you buy them separately from Parallax you will pay nearly twice the money
However I made two changes...
We are not using the 5V regulator which makes things too complicated on the breadboads, but 3.3V stabilization from 4.8 to 5.2 V batteries.
Mignon (aka AA) rechargeables are extremely inexpensive and have the five-fold capacity ( 1800mAh) of a 9V battery (350mAh).
They fit nicely in 50 cent harnesses with the same button connectors as the 9v batteries.
When in need of 5V the unregulated 4.8 to 5.2 Volts from 4 x 1.2V rechargeables will work in most cases, as with 74HC, etc.
There is one advantage of using a weak 9V: When short cutting its ends it will not melt everything down immediately
I add also a multiplexed 4x7 segment display, a standard 2x16 alfanumeric display,
some decent button switches, ten more LEDs and 220 Ohms resistors, and 5 Schottky diodes.
After a while it turned out that the best thing of all is the box it comes in.
Looking terribly cheap it is quite robust and close to perfect to hold the parts and even more...
I can buy the "ingredients" for less than the parallax price now (in Europe and Australia (!)),
but I have not yet found such a useful case below $10
Post Edited (deSilva) : 12/21/2007 8:24:02 PM GMT
I for one would like to see your various additions -- "I also add a multiplexed 4x7 segment display, a standard 2x16 alfanumeric display,
some decent button switches, ten more LEDs and 220 Ohms resistors, and 5 Schottky diodes."
What are the diodes for?
The alfanumeric displays are not always inexpensive, but there are many, many surplus offers as well as ebay.
You pay $7 (5€[noparse];)[/noparse] at most, but this already debits a low cost account considerably.
However it has turned out that such kind of display fits better the expectations (and sometimes even the resources) of my microcontroller student than a TV.
I added the diodes so we can make a simplified power supply from 3.7 Vlt Lithium batteries, and also build a low cost voltage multiplier,
generating the needed pulses with the Propeller. They can be useful for ad-hoc logic as well. Some of the sudents will have some basic
knowledge from their university, but they generally have no electronic parts at all.
A multiplexed 7-segment display is a very educative part, allowing you to experience the limits of current and timings first hand!
Furthermore a 4 digit display already allows realistic low cost devices! The ebay price for such things is below $1!
Post Edited (deSilva) : 12/21/2007 8:42:10 PM GMT
You can have a 4X5 display and only use up 5 I/O, leaving plenty of room for expansion. It would teach a bunch about display timing and some electronic stuff too. It would require some soldering and maybe a custom pcb, but a perf board would do fine. Although it would be more expensive and time consuming than 7 seg displays, its benefits could possibly outweigh the cons.
Just a suggestion
Kevin
Indeed we talk of Charlieplexing. However the benefit is not so much an electronic one, but an organizational improvement (saving pins)
Or in other words: It is too complex, when you are still struggling with the concept of multiplexing as such.
We cannot use solder irons for safety reasons, so it has to be done on a solderless breadboard, which is, well: unsatisfying.
in fact there are nice 5x7 dot displays for around $1 which fit nicely into breadboards, but the drawback is you cannot use the secondary diagonal, which is unsatisfying as well
You are quite right you need some artistic soldering to make it really work. Upto now none of my students had taken the opportunity :-(
I've worked mainly with the PIC micro cause they are the ones I know best and the learning curve to get at the same level with others MCU don't worth the effort since the gain in power is not significant enough.
My last investment (last week) was a Propeller Demo Board and I think it's the best developpement board I've ever bought. I'm very impressed by the power of the Propeller, I would recommand it to everyone. Now I feel that it really worth the effort to learn the programming langage and I discover that spin langage is not so hard to understand and is really powerfull. Education lab documents are really well made and permit a progressive learning, just hope they will be available in french sometime.
So thanks to all the Parallax team and people here in the forum who give wonderfull program example.
Happy holidays everyone. My holidays will be dedicated to the Propeller
In charlieplex's favor is that shows in a material way the effectiveness of time slicing. It's one thing to read about it, and quite another to get it working.
Charlyplexing utilizes the fact that LEDs have a high enough reverse voltage (but note: it is just 5V! Very few are aware of this!) to be used as a valve.
Charlyplexing symmetric things (as tiny light bulbs) needs an ADDITIONAL diode for decoupling.
So there are three learning steps involved:
- Multiplexing
- Decoupling using diodes
- Scannng a matrix
- Complex "Use Case": Charlieplexed LEDs
You can hapily live for years without needing the last step - or even knowing that it exists
kevin?
Wait, who am I. Lost in the masses of spin! Falling! [noparse][[/noparse]Falling! Falling!
When you look at the basic sketch (I shall include one) you will find that Charlieflexing even NEEDS common cathodes
Post Edited (deSilva) : 12/24/2007 3:52:05 PM GMT