LED programming

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does anyone here know any info on programming LEDs using microchips etc.

What it is im trying to do is setup a few LEDs to flash in a sequence, in a strobe effect.

Think of the lightbars on some police cars, fire engines, ambualnces when once side will flash in a strobe effect then the other side and bounce between each side.

Its for some models i make, which are police and fire models.

I got a pre-made one a few years ago which done this - ive tried to the website i got it from but seems they no-longer exist .

The setup they had done was 2 surface mount LEDs, a chip/pic, resistor, and a black withing with 2 legs then the 9v battery connector.

Are there any good sites i can look at for chips/pic controllers that would do this.

Also what software/hardware would i need etc.
 
I did something similar at uni with a 16F84 microchip and some assembly (or c)
Or was it a 16F87 with a 4x20 LCD? Was pretty simple anyway.

There are kits you can buy that include the programmer and a bunch of components and tell you how to do it all, not too expensive if you buy from foreign lands. I'll see if i can find one.

How many of these things are you wanting to make?

Actually I quite fancy geeking out and getting back into this kinda thing, does anyone out there own a MikroElektronika kit?
 
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You can use a 555 chip to produce a continued flashing pattern - read up on google about Astable 555 timer circuits.
 
Was just about to suggest, to get a strobe affect, you could use a 555 connected as an astable, pretty basic and cheap! and doesnt need programming.
 
I've been using a homemade PIC programmer which connects to a serial port and a PIC 16F628 microcontroller. I haven't had a chance to get much done with it yet but I started making an 8x8 LED display controlled by the PIC and a couple of flip-flops (latches). I do know PIC assembly language but I've been using a language called JAL which is a high level language which makes it so much easier to program. This is a video of what I managed to do so far:

http://www.youtube.com/watch?v=opsSAFlkIjw

The circuit for using a PIC is very basic, consisting of no more than supplying the PIC with power and hooking up the LED's to the correct pins. There is lots of information on the web regarding this, you shouldn't find it too difficult to get working.

http://picprojects.org.uk
http://www.wattystuff.net/tiki/tiki-index.php?page=PIC+Micro
 
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Can you still buy things like 555's and 741's and bigger stuff like 3055's? I used to be a total electronics nerd but I don't seem to be able to find basic components on the high street any more.
 
The highstreet is pretty rubbish for things like electronics components, you may find a specialist shop is some places but the best place is online.
 
Can you still buy things like 555's and 741's and bigger stuff like 3055's? I used to be a total electronics nerd but I don't seem to be able to find basic components on the high street any more.

You can get it if you hunt around a little. But I still have a huge junk box full of reclaimed bits, much cheaper :D
 
Better getting yourself an account with RS Components. I won't link them just in case but you'll find them with a google search. You can get some fancy LEDs from there too, like high intensity and square ones.
 
i've had a look at the 555 timers, found some on ebay few pound for 10 of them.

Ive had a look at some sites with info on doing LED flashers with the IC 555 Timer, but im not sure if i would be able to get what i needed with it.

One example would be this

8 LEDs in total.

2 Blue leads flash in a sequence of led 1 will flash quickly 4 times, then led 2 will flash quickly 4 times (roof lightbar) and continue doing that sequence.

The other 6 LED are 4 blue and 2 RED.

2 blue at the front (flash on and off - ie led 1 then led 2) and 2 blue 2 red at the back.

They flash on and off (with the back blue flashes then red flashes (the front leds could be connected to the front blue leds.)

Hopefully it makes a bit of sence.

Ive had a look at some videos of led flasher and chaser units etc, but most use different chips that you need to program (i found one site that has the HEX files you can download the simple setups etc)

But i would need a programmer - what kind would i need though.
 
Humm.....you could use decade counters along with the 555s to create the sequence. I'm pretty bored and have the day off tomorrow, so might take a look at creating a simple (non programming) circuit that can do it.
 
Ok. had a quick gander and came up with a simple circuit for the roof bar (just a block diagram, can't remember 555 circuits). I think the front and back lights could be done with a bistable flip flop (if ive read what you want to do correctly).

Edit: the decade counters i was talking about are 4071 chips
 
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Sounds similar to something I did for my AS-Level project a few years back. I used an LED dot matrix board to make a little game using a pic - the 18-X I believe.

MVC-008S.JPG


It was a few years ago but I can remember most of what it entailed. I had a pin from the PIC going to the clock of a decade counter which went to the transistors to switch on one column at a time and then the other outputs controlled the rows. As it's done fairly fast it looks like it is continually on. My game had a moving target going down one side of the screen and 3 buttons to fire a missile across at it and when you hit it that was it. bit simple but took a bit of playing with to get it sorted. Dunno how relevant this is but if you need a hand give us a shout :D
 
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