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A simple adjustable speed KITT pattern with no trailing lights is pretty easy, you can do this with a 555 timer, a few 4017 chips and some steering diodes... Optional transistors or darlington chips so that the load on the 4017 is reduced...

Now once you get into the trailing effect and other patterns it gets much more complicated, and IMO a micro can't be beat... Heck at the end of the day the micro makes even the simple sweep easier but it requires you to be able to program micros...

 

I would recommend any micro with serial communication, and a serial LED driver or two... Generally 16 channel LED drivers like this for example are more economical than lager channel ones, use two of them and you can independently drive up to 32 LEDs in any pattern by just sending it serial commands from the micro...

The micro choice is up to you and what compiler and programming environment you are setup to do or want to invest in...

You could also do it by brute force and just get a 40 pin or so micro and some darlington chips or transistors to drive the LEDs and toggle 30 ports on the micro on/off...

 

I would go with the 40 pin. Much simpler to program for a beginner than trying to use serial I/O or shift registers. You can get 40 pin DIP PIC microcontrollers.

Bob

 

That is overpriced. It is also an older chip, which means it has less power and performance and costs more than newer chips.

PIC16LF1904 would be a good choice and it is $1.99 in quantity 1 from Microchip direct.

To drive that many LEDs you want to use darlington arrays, like the ULN2003, 7 drivers per package. About $0.30 each.

Bob

 

Looking at this again, the part I reccommended is a 3.3V part.

For your purpose, you probably want a 5V part because that is about what you will need for blue LEDs. So PIC16F1517 would be a better choice. It costs 3 cents more.

Bob

 

There is also another advantage to using dedicated LED driver chips, if you want the trailing lights is that many of them will allowing individual dimming of individual LEDs on the fly, takes a huge load off the micro...

And on that subject, if you choose to use 30 I/O lines getting the trailing effect is even more troublesome to implement, especially for a newbie...

 

The micro cannot connect directly to that many LEDs because the sum of them would require too much current for it to provide. So you need an external chip to turn the LEDs on and off. The Darlington arrays that I mentioned are just 7 transistor switches in a single IC package. You would use one of these switches for each LED.

I said you need 5V to drive the LEDs because you need a little extra voltage to be eaten up by a current limiting resistor. I looked at the link and your LEDs had a forward voltage of 3.2 to 3.8V which is too much for the 3.3V PIC.

As for Coca Cola's suggestion. I agree that if you want to get fancy with the patterns, serial I/O to a driver chip might be a better idea. But, as I said before, for a newbie to programming it might be a bit difficult. Let me explain the difference.

In my scheme, you would simply control each LED with a single pin of the miccrocontroller (through one of the switches in the darlington array). This is simple and straightforward, unless you want something like the fading trailing effect that C.C. refers to. You cannot easily control the brightness of the LEDs with this scheme.

In C.C.s scheme, the micro would use just a few pins to communicate serial data to a chip designed for driving LEDs, including controlling their brightness. You would need fewer connections from micro to the driver chips, but you would have to learn about SPI and data protocols and such things, instead of simply turning each LED on or off.

Bob

 

Coca Cola knows more about this type of LED driver, I have never used one.

Are you there?

Bob

 

You need a programmer to program standard micros. They can be had for < $50 from Microchip. The PICKit 2 or 3 is an example. It connects to your computer via USB and you then program through tools that are free from Microchip. You can program either in assembly language or C.

Another option is to use the PICAXE. This is a pre-programmed microcontroller that will cost you a bit more, but it needs no programmer, just a serial connection to the computer. It is programmmed via tools specifically for PICAXE in a BASIC like language. CDRIVE is the forum expert on PICAXE.

As you can see, there are many options and it can get confusing real fast!

Bob

 

I'm here but I don't have the time to compose all the details right now, there is so much involved and personally I feel this is a giant leap for a newbie (as has become evident) to be taking on...

So here is a pretty well laid out example written in BASIC that I happened to bookmark years ago (since that is primarily what I use) for a 16 bit LED driver, this isn't taking full advantage of all the features but it gets your feet dirty on the core principles...

http://www.picbasic.co.uk/forum/showthread.php?t=10572

On thing that will make it easier to visualize is to take the hex LED value in that example code and break it down into the primary binary numbers...

Example

LED value = $34FC when broken down looks like this...

$3=0011
$4=0100
$F=1111
$C=1100

And that results in 0011010011111100 your 16 channels with 1 being on 0 being off...

Now when you get into dimming and the sorts it gets a little more complicated and how the chip does that might change between chips but I highly suggest you just get on/off flashing and patterns working first before that...

 

Yes, simple on / off status is what I was imagining when I suggested the 40-pin micro. If you want to build that first, you could still use the same micro for fading trails but the programming would get much more complicated. It might be reasonable to start with patterns that are only on / off and then move to fading effects.

If you want to make the simplest version 1.0 you can set a limit on how many LEDs can be on at that same time that does not exceed the micro's capabilities. Then the circuit becomes very simple:

1. A 40-pin microcontroller.
2. 30 or so LEDs + a resistor for each.
3. Decoupling between the power and ground pins of the micro.

I think this is the minimum hardware configuration that would work for you. All the rest of it is software.

Bob