Simple Applications and PIC code.
These little project projects were created to demonstrate the use of LED technology. All use simple PIC micro-controllers, and utilise some of our products. The HEX files and circuit diagram for each project is included, and can be downloaded for the micro-controller circuit. Circuit diagrams for any commercial parts are not however included. Any drivers can be purchased from Logic Magic Ltd.
Here is what the fire can look like. |
Image of controller and 3x1W passive driver Note. The microprocessor s shown is the one in the |
|
|
The lightening strike simulator used a very simple pseudo random time delay, actually consisting of just 7 different time delays. As each time is reached a fixed combination of ON-wait-OFF sequences was implemented. Each of the 7 flashes are different in both number of semi-flashes, duration of semi-flashes and overall “strike” duration.
The Throbbing green cauldron was created using a simple throbbing pair of green LED’s (inverted drive). This uses a simple PWM output to dim the LED’s smoothly. The whole assembly was encapsulated in epoxy with only the LED’s protruding, along with wires to connect to a battery. A standard “fogger” unit (available from Maplins, and other electronics / disco equipment outlets) was put inside the cauldron, along with the “LED Throbber”. As the “fogger” creates the mist inside the cauldron the LED’s illuminate the mist with a strange green throbbing light.
This project was done to demonstrate the capabilities of our RGB LED strip. It simulates the lights on Knightrider’s KIT car, but instead of having just one colour it cycles through all 7 colours possible with RGB.
Flickering Candle
This little project is just like all of the “everlasting candles” available on the market, only we like to think it is somewhat better than all the rest because it is truly random in it’s nature. It is best to use 2 slightly different colour 3mm yellow LED’s. Try to get one which is pale yellow, and one which is more orange. Mount the LED’s one on top of the other, with the orange one on the bottom. To diffuse the light a blob of bathroom silicone sealant, or better still non-clear “Araldite” epoxy.
This again is similar to the colour changing pedestals you can purchase these days. However, we like to think we were there first, and we also did it better and smoother. Unlike most colour changing illumination units, which just went through 1 cycle red through to green, through to blue, and back to red, or some similar order. This one is based on three phase sequences giving more colours, and a more unusual sequence.
Imagine the three colours as a triangle. Red at the top, green and blue at the bottom. If you know draw a circle of that colour around each corner so that they overlap in the centre. The exact centre of where they overlap would be white (unlike paint where R+G+B = mucky grey), also green and red light make yellow not brown.
This colour changer goes round 5/6th of this triangle each time, but then heads towards the centre. This has the effect of making the colour paler and paler until it finally becomes white, but then getting darker toward the second colour. This means that it takes 3 cycles before the sequence starts all over again.
The first sequence would be red through to green, through to blue, but when it gets to magenta (red and blue) it will start getting lighter until it becomes white. From this white it will continue to go towards green so from very pale green to darker green. It does the same again going round to yellow before going to white, and finally from blue round to cyan then up through white back to starting point of red.
The line traces the colour sequence starting with red.
If you have any comment about this fun stuff page, would like help in any of your own projects, or would like to see other projects here (including your own projects) email:
funstuff@logic-magic.co.uk
Please include “FUN STUFF” in the subject field, or your email will go straight into the deleted bin.
SiteWizard.co.uk Website Design & eCommerce Software Shopping Cart Solutions