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1  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: October 03, 2012, 12:27:48 pm
If anyone is seriously interested, I can look for the documents, I might still have them on another PC.

If you can find them, it'd be great to have the info on line as a matter of record.

It's a bit of an arse that I bought 25m of the damn stuff  smiley-confuse. S'pose we'll find a use for 'em somewhere with the stock controller. Either that or soldering practice.

In the meantime, these bad boys seem to be the best current option.

Cheers, Robert.
2  Using Arduino / LEDs and Multiplexing / Re: SM 16716 chips - instead of WS2801 on: October 03, 2012, 11:34:37 am
The Fast SPI library now supports them: http://code.google.com/p/fastspi/

Cheers, Robert.
3  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: September 06, 2012, 03:14:57 am
It's now post-Burning Man :-). There were so many people out there this year with LED projects of various compositions, so I've started a forum for LED artists and technologists:

https://groups.google.com/forum/#!forum/led-nerds

Please join if you're interested in this stuff. Discussion of the S301 hacking may indeed continue there, but I'll report back when I've found something concrete.

Cheers, Robert.
4  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: August 14, 2012, 04:54:46 pm
That was my thought too. I've had some contact with the LV hackerspace crew and there are people interested in helping, so we'll get to it post-Burning Man :-)
5  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: August 13, 2012, 12:48:41 pm
I'd be surprised if that were the case, as upthread you can see the marketing pages which mention I2C and I also opened up the controller and found an I2C chip in there.
6  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: August 12, 2012, 05:46:35 pm
It's a little tricky, my friends with the logic analysers and oscilloscopes are in Amsterdam and I'm now in Las Vegas (and not returning to Amsterdam until at least next year.) I'll check out SYN Shop (the Vegas hackerspace) and see if anyone there can help.

The first dump is the whole output; the second is a subset but it repeats like that the whole way. I know it would help if I could get video of the patterns synced to the logic analyser dumps and I'll try for that.
7  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: August 09, 2012, 05:13:29 pm
There are about 100 patterns, according to the prebuilt controller. Capturing the waveforms and playing them back is something we were going to try, but I had to leave town before Ian (from Dangerous Prototypes) came back with his Bus Pirate :-).

Building a completely custom controller and running custom patterns on these LEDs is kinda the point, if I can't do that I might as well use the built-in controller.
8  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: August 09, 2012, 01:26:14 pm
With the help of some friends from the Amsterdam Hackerspace and the Meta group, I've hooked the controller for these strips up to a logic analyser and got some dumps. Bad news: it still doesn't make sense. Firstly, here are what a couple of the patterns look like looked like on a scope:





In both, the top is the clock line and the bottom is the data line. According to people there who know something about I2C this is not what an I2C clock signal ought to look like.

More interesting, here are a couple of dumps from the http://www.saleae.com/ a friend bought. Screen caps follow, but you can download the software from that link and play with the attached dumps yourself without owning the hardware.




It still doesn't make sense. For some of the patterns, after an initial burst of enthusiasm the controller seems to be sending nothing, despite the LEDs happily continuing their pattern. Maybe all the controller is doing is selecting one of a hundred or so patterns and telling the D7001 which one to display.

Links to the data files for the Salae: http://dl.dropbox.com/u/1432370/S301/R700-A%20LedController%20mode%2017.logicdata, http://dl.dropbox.com/u/1432370/S301/R700-A%20LedController%20mode%2018.logicdata

Does any of the above help anyone? Doesn't look like my original project is going to come off now smiley-sad.
9  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: May 17, 2012, 07:30:40 am
I'd guess the Chinese manufacturers are reluctant to give out datasheets because they're worried about other manufacturers ripping of their designs. Which is funny, because the specs at least look a lot like these NXP chips:

http://ics.nxp.com/products/led.drivers/

Specifically:

http://www.nxp.com/documents/data_sheet/PCA9626.pdf

(I may, however, be talking completely out of my arse here. I would welcome this being pointed out if it's discovered by someone who does indeed know what they're talking about.)

Edit: Dicking with google translate I found this, which I think is meant to be a whitepaper, which has a little more information than is on the above diagrams (but not much):

http://translate.googleusercontent.com/translate_c?rurl=translate.google.com&tl=en&twu=1&u=http://www.cntronics.com/public/art/artinfo/id/80009061&usg=ALkJrhhmkOplKxDAMNvsX4G0PuRsMoxSbQ

10  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: May 06, 2012, 03:52:28 am
Very keen to hear an update on this when you've got something to share, Daniel :-). Just about to order some of these strips myself, for this year's project.

Any first-hand info on the voltage for these strips, by the way? Is it 5V everywhere, or 5V signalling and 12V to power the LEDs like the LPD6803 strips I used last time?
11  Using Arduino / LEDs and Multiplexing / Re: Cheap addressable RGB strip - how to control? on: March 05, 2012, 04:39:09 am
Check this thread out. The author of the FastSPI library has a sample of a D7001-based strip and is planning on adding support.

I note the eBay URL you pasted says 12V but you say the strips are labelled 5V. Which is it? How much current do they draw? I'm interested in using these strips in a project of my own.

Cheers, Robert.
12  Using Arduino / Project Guidance / Re: Arduino/clone with Bluetooth and SD card reader? on: September 13, 2011, 11:59:17 pm
Thinking about it some more, my project requires pushing a 24-bit 16x40 pixel display over the air at 60Hz, which is a data rate of 115200 bytes/sec = 900kbps, which from my reading seems to be well in excess of what Bluetooth can deliver. So that means 802.11b/g wifi, for which under 1Mbps should be a walk in the park.

Therefore, the combination of the Arduino Pro and WiFly shield being fed by off-board storage seems to be a more practical solution.

I'm pushing the RAM on the ATmega328 hard though, I might even have to look at an ATmega2560-based board.

Cheers, Robert.
13  Using Arduino / Project Guidance / Re: Arduino/clone with Bluetooth and SD card reader? on: September 13, 2011, 12:44:27 am
[I'm not sure why you thought that was originally the wrong forum, but anyway...]

From a link-on-a-link after a google of "Arduino Bluetooth" I've found the Daisy 1T with integrated Bluetooth and SD card reader for an entirely reasonable $75, so that looks like what I want: http://daisyworks.com/products.html

Cheers, Robert.
14  Using Arduino / Project Guidance / Arduino/clone with Bluetooth and SD card reader? on: September 12, 2011, 04:30:21 pm
Does anyone know of an Arduino variant (or combination of shields) I could use to get Bluetooth and an SD card reader? Bonus points if it's either UNO-sized with all those features built in or a stack of Mini-sized shields.

Cheers, Robert.
15  Development / Other Software Development / Re: UPDATE - Linker Problem — Arduino Uno and Xcode (cont'd) on: May 08, 2011, 03:32:26 am
Good news, using the Makefile supplied by avenue33 I've successfully uploaded the Blink script to my Uno!

Xcode4 still won't acknowledge the existence of the template, but I guess that's just an afternoon of manual-digging. I'll post here when I have anything more to report.

Cheers, Robert.
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