View Full Version : Circuit Cellar article - June 2010

Al Booth
05-28-2010, 05:18 AM
Interesting article in the latest issue of Circuit Cellar. It is titled "Custom Interpreter Development" and was written by Chris Cantrell. He discusses a movie system that uses a Propeller, a 48x32 LED display and 2 AY-3-8910 sound chips. The interesting part is how he builds a "custom CPU". A code download link is provided.

After my first reading, I have more questions that answers, but I haven't look at the code yet.

It's nice to see another article published about the Propeller.

And congratulations to Tomas Rokicki,Ěhis SD driver in OBEX is credited in the article.


05-28-2010, 06:45 AM
Sounds interesting. I was in a newsagency in Brisbane a couple of months ago and found a copy of the March issue of Circuit Cellar. It was $20 but I was so impressed I bought a subscription. The May one has just arrived and this also looks like my sort of magazine. So I'm looking forward to the June issue.

Regarding the sound chips, I see that there is a thread running where this is now working in software, so if one works, maybe it is possible to use another cog and have two working? That could save some more chips.

Re custom CPUs, pullmoll seems to be creating a new one every week. Something very exciting is happening with the Propeller at the moment and it is great to be part of this.

www.smarthome.viviti.com/propeller (http://www.smarthome.viviti.com/propeller)

05-28-2010, 07:42 AM
I just love Circuit Cellar.
Some of it is over my head but I
still like to look at everything..
I enjoy the ads too!
This is a very good article....
Here is a shot of the LED display
from it.

Oldbitcollector (Jeff)
05-28-2010, 09:27 AM
You guys kill me...

I can't even buy the June issue on their website.. (Still selling May)

Guess I'll be stopping by Borders with my fingers crossed tomorrow night.


Are you Propeller Powered?
Propeller Feature Projects: PropellerPowered.com (http://www.propellerpowered.com)
Visit the: PROPELLERPOWERED SIG forum (http://www.savagecircuits.com/forums/forumdisplay.php?29-Propeller-Powered) kindly hosted by Savage Circuits (http://www.savagecircuits.com).

05-28-2010, 09:58 AM
My copy arrived today. Haven't read the article yet. (I've subscribed since almost the beginning - I missed the first 3 or 4 issues (I think), but I have the original bound photocopies of those issues that Circuit Cellar sold after they ran out.)

05-28-2010, 10:30 AM
There is also a great article about touch switches.
It shows a cute little Atmel touch switch demo board,
I'd like to get one. The guy says it even worked well
when he wore gloves.


Mike Green
05-28-2010, 10:48 AM
You can do capacitive touch sensing with a Propeller: http://forums.parallax.com/showthread.php?p=864475

05-28-2010, 11:14 AM
yes, the article talks about doing touch switching using any
mcu with a ADC and a timer but this Atmel chip is supposed
to be some sort of super flippin duper solution that makes
it worthwhile to add it instead of just creating your own.

Could just be sales hype though.

05-28-2010, 11:52 AM
Is this Chris Cantrell on the forum?

Oldbitcollector (Jeff)
06-02-2010, 01:21 AM

You can now order the article from their website (CC) with this link: ($2.00)

secure-nt3.localweb.com/cgi-bin/cart32.exe/cellar-AddItem (http://secure-nt3.localweb.com/cgi-bin/cart32.exe/cellar-AddItem)


Propeller Feature Projects: PropellerPowered.com (http://www.propellerpowered.com)
Visit the: PROPELLERPOWERED SIG forum (http://www.savagecircuits.com/forums/forumdisplay.php?29-Propeller-Powered) kindly hosted by Savage Circuits (http://www.savagecircuits.com).

06-02-2010, 01:48 AM
Hey OBC... that link doesn't work. It shows an error message.

You can use this one instead www.circuitcellar.com/magazine/ (http://www.circuitcellar.com/magazine/) and click the "Purchase This Article" button on the page.


Post Edited (wjsteele) : 6/1/2010 6:53:19 PM GMT

Oldbitcollector (Jeff)
06-02-2010, 01:59 AM
Sorry about that...

Try this.. He's the FEATURED ARTICLE.

www.circuitcellar.com/magazine/ (http://www.circuitcellar.com/magazine/)

Propeller Feature Projects: PropellerPowered.com (http://www.propellerpowered.com)
Visit the: PROPELLERPOWERED SIG forum (http://www.savagecircuits.com/forums/forumdisplay.php?29-Propeller-Powered) kindly hosted by Savage Circuits (http://www.savagecircuits.com).

06-02-2010, 02:58 AM
@ mpark,

If I recall, Tom Cantrell has been writing for Circuit Cellar for years, maybe over a decade. I haven't subscribed for some time now. Good mag IMHO, though.

Harley Shanko

06-05-2010, 10:28 AM
Yeah! People confuse me with Tom Cantrell sometimes. But I am Chris Cantrell, and no relation to him at all! I am honored to see you guys talking about my article. I wasn't even aware that there was an AY38910 emulation project going on on the propeller. People are doing some awesome things with the propeller!

06-05-2010, 10:30 AM
Oh. Here is the project on YouTube:

06-05-2010, 12:45 PM
@ Chris,

Sorry. Appears I slipped a cog or two.

Harley Shanko

06-05-2010, 10:34 PM
Hey Chris, great video. Some of those "days" are pretty hilarious. I'd better go check out your article.

06-05-2010, 10:42 PM
OT: I can't wait to drop "super flippin duper" in to a batch of clear sales hype at the right time to make it obvious. Thanks Holly! The Potato eagerly awaiting just the right over-hype meeting... [evil grin]

Propeller Wiki: Share the coolness! (http://propeller.wikispaces.com/)
8x8 color 80 Column NTSC Text Object (http://obex.parallax.com/objects/550/)
Wondering how to set tile colors in the graphics_demo.spin? (http://forums.parallax.com/attachment.php?attachmentid=70768)
Safety Tip: Life is as good as YOU think it is!