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Discussion Starter #1
Howdy all It has been some time since I have been here ( getting a new Truck
then getting Hours cut at work
) and I need to get back into something less stress full.
What I want to do is build two Circuits for a work caboose. One is a random Flickering flashing Circuit IE a fire lighting effect, hopefully some thing that will flicker two LED's. Second Is an Alternating dimming flashing circuit, a circuit that will turn on the first LED dim and bring it up to full then drop down and the turn on the second LED dim and bring it up to full and back and forth, with a control to speed up or slow down the effect . Like a Mars light effect. I tried to find circuits on Google but I couldn't find much. I hope some one here can help me with this, I really need a distraction from the Crap in the world right now. Thanks all for the Help
 

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I know that somewhere on here there was an explanation of a random flasher circuit using a transistor radio. Basically you connect the LEDs to the speaker output and tune in an AM station. The modulation of the signal will cause the random flicker of the LEDs. Stick to talk radio, if you tune in a music station the lights will flicker to the beat.

For a more regular flasher interval, I have experimented with LED bicycle tail lights. Cheap, easy to come by and the circuit boards are tiny... You can fit'em just about anywhere.
 

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In the "Party goods" aisle at Wal*Mart they sell a "Tiara" for little "Princesses" that has a sequential flasher circuit and 5 red LEDs in a circle. The leads are long enough to bend the LEDs back toward the center so the circular sequential flashing gets masked a bit. Burried inside a firebox or under some campfire stick it can make an effective fire simulation. It runs on button batteries that the instructions say are not replaceable, but they pop out fairly easily... The Tiara was 98 cents last time I saw it. (Replacement batteries will cost MORE!) It would be easy to supply 3V DC to it externally from some other source.
 

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I'd program an avr chip, but that's just me
 

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Discussion Starter #7
Thanks all for the Tips so far, I work at Walmart
so I will see if we have the tiara and try it. I have tried the radio setup but it didn't work very well. I am not very good with electronics but I can soder and can follow a schematic and build it whit the best of them
. I hope some one out there has a schematic that they will post or send me
. I have lots of the 555 chips that i use in an alternating flasher and was hoping the was a circuit schematic that could use it for the Mars light effect. Thank you all for the help.
 

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Jerry, yer link gives my browser all kinds of fits... something about my intranet being shut off by default... silliness.


Then I noticed you have the http part on twice. I tried editing it out and got a google search page that then took me to the correct place...

Here is the result of my being able to see the page. Hope this helps anyone else whose IE got the sillies.

http://www.trainelectronics.com/MarsLights/article.htm

Nice article. I think he could have used some surface mount LEDs and made the whole thing lots smaller.
 

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Discussion Starter #12
Jerry Thanks for the Link, I think I will order one of the kits he has. Semper got the Tiara, looks like it will work just need change some of the LED's to yellow. My niece will love the Tiara part. I think that if I knew how to program chips this would be simpler.
Thanks every one for the help so far. Its nice to know that I can jump back in after a year.
 

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I just programmed some chips for Larry to do that. They're 20 pin dips and cost about $2.25 each.





 

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Discussion Starter #14
How and what do you need to program chips?
 

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Posted By jasher817 on 02/07/2009 10:08 PM
How and what do you need to program chips?



Well, some knowledge of a programming language helps (or time and ability to learn a language); Most folks use C, Basic, or some even use Assembly language. Then you need to find a chip ( a micro-controller) that has all of the hardware I/O and memory required for your application. And it needs to be supported by a software language that you know how to work with. You then design the hardware circuit to meet your requirements. Assuming you have the proper development software available, you can begin writing the software to make the hardware do what you want it to do. Actual programming may only require RS-232 connections to the micro, or it may require purchasing an in-circuit programmer. After you program it, then the fun begins ... why doesn't it work?

It isn't a simple process. However, for those of you interested in getting your feet wet, I would recommend the "Pic-Axe" as a great starting point. It is a low cost and easy way to learn how to use micro-controllers. Good enough for simple projects.
 

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I program them in assembler. Not something to learn for one project. Want me to send you one?

Here's a pin out:



And pin functions:

1. /Reset â€" Pulling this pin to 0v resets the chip, setting the speed back to the last programmed speed. You can also use this to turn off the light with a digital signal, if you like. Pin 1 is marked by a small circle on top of the chip.

6. /Faster â€" Pulling this pin to 0v speeds the light up. It will speed up a little each cycle as long as you hold this down.

7. /Slower â€" Pulling this pin to 0v slows the light down. It will slow down a little each cycle as long as you hold this down.

8. /Original â€" Pulling this pin to 0v sets the speed to the original speed I set when I made the program.

9. /Save â€" Pulling this pin to 0v saves the current speed so it will be used next time the chip is reset or turned on. Hold it low for a cycle.

10. 0v â€" The minus power supply to the chip.

20. +v â€" The positive power supply to the chip. The chip will work on anything between 1.8v and 5.5v. Voltages higher than 5.5 volts are not recommended.

12 â€" 19. LED outputs. Put the â€" side of your LED’s to pins 12 through 19, and the + side to the voltage you’re applying to pin 20. Each pin is good for 40mA max. Only 1 LED is turned on at any time, so you can use 1 dropping resistor. If you have bright white 3v LEDs of 40mA or less, you can just run the whole thing from a 3v regulator or battery with no resistor. A battery should run it for a long time.
 

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Discussion Starter #17
Torby, That would be awesome. I look at the Pic-Axe site and man I am out of my League here. I was hoping for some thing simple that I could do my self and wow, I now remember why I don't like complex circuits. Some day I mite give the Pixaxe thing a go when I got more money to spend. As always Thank you all for looking and helping.
 

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I spent 2 evenings on the program for that, but then I have 3 degrees in electronics and computers.
 

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Getting started with the PICAXE can be very easy and inexpensive -On my web page there are links to a number of presentations that I have given at the ECLSTS and national conventions that highlight just how trivial getting started can be.

Have a look at this presentation, especially slides 14 - 47.
http://www.trainelectronics.com/NGRC_2008/National_GRR_Presentation2008-rev5-4-as_presented_files/frame.htm


That set of slides shows how to do simple flashing that may be just what you are looking to do.


There is also detailed information on setting up for programming the PICAXE here:
http://dbodnar.com/motor_control/



dave
 
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