starting to understand (leds, lighting)

Forum 2005-2010 (read only) Hardware Troubleshooting
1

Hey everyone,
First of all, I've got to say that I'm a designer (mostly visual-concept), I know very little of programming, and almost nothing of experimenting with electronics.

Right now I would like to expand my knowledge in the fields of interactive lighting and LED matrixes/screens.

I've seen Arduino and, well.. it seems the easiest way to start off.

So, I'd have heaps of questions, for now:

  • what version of Arduino would you suggest purchasing?
  • how about the other components? Which ones would be easiest to connect, to start to doo something tangible, and then axpand the size/complexity?

and, most important:

  • where and how should I start learning, in order to get good and solid results?
    (I'm already ok with some basic processing)

I have seen the "learning" section of the website.. what I would really appreciate, are some practical suggestions.

Thanks in advance!

2

How I started !!!!! Which was only a couple of weeks ago now was :-

Got a Seeeduino , and Arduino Xbee Shield
http://www.skpang.co.uk/catalog/product_info.php?products_id=391

Already have LEDs and Resistors etc.
Started playing with programming a sample knight rider running light.

A couple of days later I sent for :-

MCP23016-I/SP 16 Port Expander with I2C interface
DS1307 I2C Bus RTC
32.768kHz Crystal

Now I have a knight rider display 16 LEDs , which transmits the time via the xbee every second.

Next I want to be able to make my own Bare Bones Board, and make it do something useful.

3

oh, thanks for the reply!

(I guess I really have to build some vocabulary in the field)

I'm wondering, what are the peculiarities of seeeduino?
Then, it would be great if you could explain in detail what's the role of the peripherals you listed :slight_smile:

So I can get the overall picture, and speak the same language.

4

The seeeduino is just a standard Arduino Board clone.
It`s just like any of the other clone boards, But it does have a mini USB other than the normal USB B , and it uses surface mounts components.
( Bad idea , if you want to use it for prototypes designs after )
I have no real aim; I just want to learn programming.

The other components are a real time clock and MCP23016-I/SP, which is an easy way to add more I/O ports.

It`s all means to a ends, where your programs slow get more and more complex as you learn.

I guess you need to think !!! What you want to achieve in the end.

5

Hi Arlon

I see that you're particularly interested by the bright side of the force. Well, if I could give you one advice : buy a looooot of leds. Don't worry about the size, etc... but just buy lots of them.

My best advice would be to go to an ebay store, where you can find some really neat prices. I bought my first batch from HKJE Led Center. That's one amongst many.
http://stores.ebay.com/HKJE-Led-Lamp-Center
The LEDs are not always calibrated, wich means that some are much brighter than others, but don't worry, for prototyping, you don't need that.

Then, I would recommend the 2 magic chips : MAX7219 and TLC5940.
The first is useful for driving LED matrices. You can drive an 8x8 matrix using only 3 pins from the Arduino.
The second is really nice for driving up to 16 LEDs with individual control on each LED brightness.
Both chips have a lot of good tutorials and libraries.

You might also want to use some good old Shift Registers (74HC164). It allows you control up to 8 outputs, using only 2 on the Arduino.

Finally (but this will come way later), you should have a look at the ULN2803 and UDN2981 chips, those will be useful when you'll want to grow your project (more brightness == more leds > more amps, etc...)

About learning how to use the thing : the playground && freeduino.org
Best starting point. In addition, you should check some useful blogs.
http://antipastohw.blogspot.com/
todbot blog – Random experiments, circuits, code, rapid prototyping, sometimes things to buy, and the odd tune by Tod Kurt.
http://www.arduinofun.com/
...
(and mine, of course ^^)
http://melka.one.free.fr/blog/

Last thing : I bought my Arduino NG about 3 years ago, never had any problem with it. I'm not sure how the other boards reacts to the passing time, but my bet would be that you buy an official board from the original makers
http://tinker.it/ukstore/product_info.php?cPath=29&products_id=88
Seems to be out of stock, so I'd go with

(damn, out of stock too)

Good luck ^^

melka

6

Another not very well known chip I am using right now is the AS1107 which doesn't require any multiplexing and will run an 8x8 matrix. There was no code available as examples so i had to work it all out from the datasheet and was pleased with myself that i was able to do that so easily :slight_smile:

Another nice chip is the 74HC595 shift register which is easy to program for.

Take a look at some of the stuff I have done recently with LED's and Matrices - Electronics on Vimeo

7

Mike, do you have the source code for your AS1107 driver?

8

the as1107 is the same as the MAX7221. the code should be pretty the same for both. The only difference I can see is that the current limiting resistor calculatinos are slightly different

9

I have emailed the code to Solarwind.

10

Since you're going to be learning about both Arduinos and electronics, it's worth considering buying a solderless breadboard (or a couple: they've gotten so cheap that it's worth having more than one around so you can work on more than one project at a time) and an Arduino that can plug into it. The Arduino Nano, Pro Mini, Boarduino, RBBB, and DuinoStamp are all Arduino-like boards designed so they can plug into a breadboard (you'll usually need to solder compatile pins to the board so they'll fit the breadboard).

Eventually, you'll probably want to buy other Arduinos (possibly including standard-sized ones that support a shield) that you can dedicate to specific projects. Or you may find that the smaller boards are more convenient for plugging into your cusom electronics.

Ran