All the other parts on the parts list can be found at mouser.com I got all my parts from a local electronical store in the town over from mine, I’m sure you will be able to find most of the parts locally, but mouser is a good place to find the Opto-coupler (and other parts) if you are having trouble finding one, or too. Also a converson table helped me figure out what kind of compactors I needed, not all brands do measurements in Pico farads.

Once you get all your parts, you can start putting everything together. The best way to start is on a Proto-board, it will save you a lot of time as you will be able to check if you have the LEDs positioned correctly among other components. One tip on putting the proto-board together, you want the 20mhz crystal and the two 22pf capatiors as close as possable to the PIC, you can see how close mine are in the photo above. Once you get everything setup and working on the proto-board, its time to move to a project board, and solder all the components to the board.

I’m no great PCB artist, and there is probably a better way to set all this up on a project board, but all I did was take the way I had it setup on the proto-board, squish it, and move it to the project board. It was that simple. the project board did take a lot more time to set up even though I had my proto-board to follow, mainly because of the soldering. I had flux on my hands for days! A few tips for the Project board: never solder directly to the two ICs, buy some dip sockets. And if you are having trouble finding a good power supply, a 9v battery works fine, I had my rechargeable 9v hooked up and synced for two hours and it didn’t skip a beat once. Oh, and a note on the photos of the project board, I’m using switches instead of buttons, it doesn’t matter witch one you use, but make sure that they are 5v when not pressed and 0v when they are being pressed. This site is really more of an overview than a actual step by step Tutorial but to go through every solder point would be murder, I’ll add more stuff as it arrives, ask any and all questions to the LSDJ-MC2 group.

Much love and respect to firestarter and the whole LSDJ Community.

There are some great resources to get you started on the twitter home page under the API section. Since you’ll need to get a key and stuff – I’d recommend at least logging into twitter, and then checking out this page. It has a nice visual representation of how the API works. Take a look at that, if you don’t understand something don’t worry it doesn’t matter.

The absolute first thing you’ll need to do to get started, is to get a key from twitter. You can do this by logging into twitter, and then registering a new twitter application. Just fill out a bunch of crap, or make it real – like most things appearing to have officiality, in reality it doesn’t matter. When filling out the application page make sure you pay attention to the Default Access type. I need read and write because I’m pushing code to tweets (you can change this later if you missed it). Once you register your app, you’ll get some important items: Consumer key, and Consumer secret. Copy those down, or leave the page open because we’re going to be using those in a second. You’ll also need you’re Access Token and Access Token Secret to push tweets from the web. You can find those by clicking on My Access Token on the right hand side of the page when viewing your app page.

Now that you have your keys we can start getting down to business. You’ll need to pick a php library to help you push/pull the tweets you want, or you can design your own. I’m not going to design my own because I don’t believe in reinventing the wheel when it comes to code unless you are trying to learn something, and fuck learning! Design your own if you want to though – doesn’t seem too complicated. Twitter lists some php libraries, for this walk though I’ll be using this one by Matt Harris. Download the class and upload it to your server. He, just lists the source, so you’ll have to save it to a php file, name it tmhOAuth.php so you don’t have to change the scrips. Once uploaded it’s time to setup everything. The keys you just got go into a php file – you can see Matt’s examples for an idea heres Matt’s tweet example:

<?php

require 'tmhOAuth.php';
$tmhOAuth = new tmhOAuth(array(
  'consumer_key'    => '',
  'consumer_secret' => '',
  'user_token'      => '',
  'user_secret'     => '',
));

$tmhOAuth->request('POST', $tmhOAuth->url('statuses/update'), array(
//'status' => utf8_encode($ message)
  'status' => 'your tweet goes here' //changed this nlarion
));

if ($tmhOAuth->response['code'] == 200) {
  $tmhOAuth->pr(json_decode($tmhOAuth->response['response']));
} else {
  $tmhOAuth->pr(htmlentities($tmhOAuth->response['response']));
}

?>

It’s pretty straight forward the 4 keys you’ve been gathering go into consumer_key, consumer_secret, user_token, and user_secret respectively. I’m going to be using a var where “your tweet goes here” is. It will probably end up being something like: XML->$var->tweet. You will want to change it to fit your needs unless you’re going to hand code your tweets each time – which would totally defeat the point.

So far – you’ve setup an app, got some keys, and made your first tweet (hopefully). Next we’ll be using Matt’s auth.php example to allow other twitter users to make tweets from the same app page. You might want to do this if you have multiple websites that each have their own XML feeds, and twitter accounts, but you only want to use one app to do everything. You could just repeat the steps above for the individual websites/twitter accounts – but I have 30+, and I want to minimize as many steps as possible and keep it all in one cron job.

Load the auth.php on your server and make sure to put your consumer_key and Consumer_secret in the correct place. Then load the page up in your web browser – we’re going to use this page to grant access to the app for the other twitter clients. Once the page is up and running it should look like this:

Click on Allow Application (callback), that will bring you to twitter where you can login and approve the app you just made, or if you recently logged in it will just ask you to allow it. Neat huh? Once you allow the app, it will kick you back to auth.php – but this time it will display some information about the twitter account you just authorized, which is completely worthless for what we’re doing. What your going to need to do is add these lines of code to the auth.php file to get the Access Token and Access Token Secret:

// already got some credentials stored?
} elseif ( isset($_SESSION['access_token']) ) {
  $tmhOAuth->config['user_token']  = $_SESSION['access_token']['oauth_token'];
  $tmhOAuth->config['user_secret'] = $_SESSION['access_token']['oauth_token_secret'];
 //this is the part to add
print "user_token: " . $_SESSION['access_token']['oauth_token'];
  print "<br />";
  print "user_secret: " . $_SESSION['access_token']['oauth_token_secret'];
//done adding stuff
  $tmhOAuth->request('GET', $tmhOAuth->url('account/verify_credentials'));
  $tmhOAuth->pr(json_decode($tmhOAuth->response['response']));

It’s really simple – you’re just adding code to print the Access Token and the Access Token Secret to the screen so you can save them to get a temp token and tweet with that user. Save and reload the page to get the new values. Copy and paste those two values back into the tweet example we used above (user_token and user_secret respectively) and run it, you’ll tweet out with the user you just allowed.

That’s it!

Store your access tokens somewheres so you can call them later. SQL would be a good place rather than plain text, but I’ll leave that up to you.

I’ll explain basically what’s happening with the scrip to get your access for other users, if you’re interested but you don’t need to know this… Once you have authorized your app with another twitter account you get a few important values. These are the Access Token and Access Token Secret. You need those two values to get temp access to be able to tweet for an authorized user. You use those two values (and some others provided by Matt’s tmhOauth.php) along with your consumer_key and consumer_secret to ask twitter for temp access to tweet. That access expires, but since you have the Access Token and Secret you can ask for temp access any time you want. If you want to know what exactly is going on behind the scenes, twitter has a great page about it.

In closing, we’ve gone though all the steps to get on to twitter and your scrips/websites should be up and running by now – or at least the framework. I just have a final thought about twitter’s new authentication process: It’s kind of like while I was dating you twitter, you wanted it bear back (and who could blame you), but now that we’re married, I have to ware a rubber? – What’s up with that?

All the code in this article falls under the Apache 2.0 License, and credit where credit is due thanks to Matt Harris

First, you’re going to need to signup for a Google Maps API Key. Once you have your key you can add the API to your site like this in the head section of your page:

    <script src="http://maps.google.com/maps?file=api&v=3&sensor=true&key=your_key_goes_here"
            type="text/javascript"></script>

Part of the agreement to use Google’s API is that you have to keep your site free, meaning you can’t charge for access. If you want to charge for access (iphone apps etc) – your going to have to purchase a license from Google, they start at 15g’s so… yeah… keep that in mind.

Now for some custom icons:

custom google maps icon

First, you want to declare your vars for the new icon, you put this outside of your load() function so another function on the page can access it. Also, FYI this is all in javascript…

    var beericon = new GIcon(); //sets the man var
    beericon.image = 'image.png'; //locates the image
    beericon.shadow = 'images/shadow.png'; //shadow if you want a shadow - transparent png
    beericon.iconSize = new GSize(70, 50);
    beericon.shadowSize = new GSize(90, 50);
    beericon.iconAnchor = new GPoint(35, 50);
    beericon.infoWindowAnchor = new GPoint(35, 0);

Those are the major parts to any custom icon. You can fool around with those settings if you want to change the size and image locations. We’ll call those vars down in the load() function later.

Next, you’re going to want to load a default javascript function to start the maps object in your site, you can do this in the body.

  <body onload="load()" >

Pretty, simple right? You’re just telling the page to load the load() function on load. Enough loads for ya?!

So, in the load function you’re going to want to start a map, and load a location, and display the custom icon.

	var usa = new google.maps.LatLng(37.0902400,-95.7128910); //locates to the USA
 function load() {
	map = new google.maps.Map(document.getElementById("map")); //sets map to the map element you have to have a <map> element in your html code
	map.setUIToDefault(); //just default UI
	map.setCenter(usa,4);	//usa call the above var, and 4 is the zoom level.
	var point = new GLatLng(37.0902400,-95.7128910); //you need a lat lng for the marker
    map.addOverlay(new GMarker(point, {icon:beericon})); // takes the vars from beericon and the lat lng from point and pushes it to the map
} //end load()

The final thing to do is to display custom icons for each location, in the case of Kayak they put custom prices in every icon. You could make 2,000 different icons if you wanted. Or you could get PHP to do it for you using the GD library, great tutorial here. Of course you’d have to make the php script – but that’s pretty simple. More to come…

Here is the project up and running:
]]> http://www.neillarion.com/blog/?feed=rss2&p=57 0 http://www.neillarion.com/blog/?p=31 http://www.neillarion.com/blog/?p=31#comments Tue, 05 Jan 2010 04:32:47 +0000 admin http://www.neillarion.com/blog/?p=31 I’ve looked into LED matrices and it looks like most of the DIY ones (one, two) use a micro-controller to operate several shift registers. Most shift registers are capped at 8 outputs, and that just seems silly to me, so I’ve looked into getting a dev board for the STP16CPC05 – Low voltage 16-bit constant current LED sink driver from STMicroelectronics.

Mine is on the way in the mail, there were only two in-stock at digi key at the time of writing this, so I hope I can help you decide if the STP16cpc05 is the way to go for your next DIY LED matrix in future posts.

My plan is to design a large LED matrix (8×24), that will be easy for one to reproduce. I’ll supply the code, and the pcb design – it will be up to you to build

Wish me luck!

Neil

I’ll talk a little bit about the details before I post all the pictures and code. First, I guess I should list all the parts. If you’re interested:

• Two Gerbil plastic balls (one large and one small)
• One arduino
• two servos from HVW
• An accelerometer, Parallax H48C
• I used a 7805 to get 5v to power everything.
• Wire, and a terminal connector.
• Solder, hot-glue… etc, etc..

I didn’t take any photos of the build process, which is why I’m down playing this as a tutorial, this is just a preview.

I’ll talk a little bit about the code, then talk about things I wish I would have done.  Somethings to consider before looking at the code:  First, I use two servos, one gets sent the direct corodinates to move to, and the other gets sent the exact opposit because it’s mounted backwards, and when you say “go forward” to one servo, you have to say “go backward” to the other to get it the entire ball to move forward (yeah, I know this is retarded).

(this is where the code will go, I have it on my other computer)

What I wish I would have done to make the build better: First, I would have came up with a better way to attach the inner ball to the outside, and would have done so by only using one servo. For my next build I plan on using shock absorbers to connect the two balls, which should give the build a more professional and durable look, and avoid the need to rip apart another Atari cartridge. Oh, and I would never use Ni-cads again – never. Li-po all the way.

That’s all for now.

Sill dreaming up v2.0….

ouch my bottom

After I was done cutting the bottoms off I prepped the end caps with an old T-shirt and rubber band:

cover up that hole

Once finished doing this to all five of the water bottles, I stared assembling them with hot glue:

Hotted Glue

Now you should have your tower starting to take shape. What I did next was cut a hole in the side just above where the you want the dirt to settle, this allows air to get inside, access to add dirt and other crap should you need to. One thing to consider when cutting these access holes is that cutting into the plastic is going to make it less structurally sound – I had to add supports to the holes I cut because I made them too big.

Alright, your going to need something to stand your tower in – something to support it. This is where my design and the one from the ReadyMade differ. Their design calls for a 10 gallon jug. Like the kind that windshield wiper fluid comes in – you don’t want to use one of those, but that’s the simplest thing I can think to relate it to. I just used a bucket, both have their merits – the bucket is easy to empty – my cat likes to drink out of it. So, go with which ever, but the one thing I have to recommend when putting it up is to account for the fact that it’s going to be heavy with all that dirt in the individual containers. It might tilt to one side, and could become unstable. Just be careful when you put it up. Once you got it up, you can add water, I put a pump in the bucket and have it on a timer to water every day. You could go all nuts and add an arduino and a way to sense moisture, but I think that would be kinda nuts for this unless you were to expand the setup with more columns.

Check it out – finished:

Finished!

Finished with LED lights installed