"Mini-Beacon" miniature programmable LED Flasher that is based around a PIC12F629 microcontroller

This project, called "Mini-Beacon", is a miniature programmable LED Flasher that is based around the PIC microcontroller.  This project grew out of an idea and recommendation posted on RunRyder.com.  The Mini-Beacon basically simulates the light emitted from a rotating light beacon such as those used in older police cars and fire engines.  As seen from the observer's perspective, as a real rotating beacon revolves, a dim light slowly ramps up brighter and brighter until a flash is seen (light facing directly toward observer), then as it continues rotating, the light slowly dims out and a pause is observed until it repeats over and over again.  Well, the "Mini-Beacon" simulates this exact effect!  The user can also choose 1 of 12 different flash patterns to be repeatedly displayed.  These patterns include slow, medium and fast rotational beacons (ramp-up & ramp-down speeds), and 3 different selectable flash patterns (single, double and triple flash).  This selection is made by simply shorting a small jumper on the driver board.  This setting is retained in memory so that every time the "Mini-Beacon" is powered up, it will display this pattern. 
If this was not enough, the "Mini-Beacon" also allows you to run it in "free-running" mode (connect battery and it repeatedly flashes), or you can control it (on/off) using a spare receiver channel on your R/C receiver (you can use a transmitter stick or switch).   The setting is accomplished using two small jumpers on the board and is described below in detail.  Additionally, and most likely most important... you can also control the Mini-Beacon using a "Mini-Flash" Controller by simply plugging them together!
Design Criteria Summary:
1) Design a simple, cheap but effective "Rotating Beacon" simulator/driver
2) Design so user can easily choose 1 of 12 flash patterns
3) Lightweight and simple to build (DIY)
4) Circuit powers off of existing R/C servo connector
5) Use servo signal to turn on or off the flashing Beacon effect
6) Powers a bright LED (around 600mA max... a one (1) watt Luxeon looks great!)
7) Listen to customers and their needs!   :)
Parts & Tools List ...
1) One (1) PIC 12F629 Chip (preprogrammed with Mini-Beacon code)
2) Two (2) 10K ohm resistors
3) Two (2) 2.2K resistors
4) One (1) Servo Lead/Pigtail wire for Mini-Beacon
5) Four (4) 2 pin header (male) - 3 for Jumpers, 1 for LED/output connector
6) One (1) 2N2222 or PN2222A NPN Transistor
11) One (1) two-row header (mating connector for Mini-Beacon output pins)
12) One (1) piece of heat shrink tubing for assembly
13) Two (2) Shorting Jumpers (one for run mode and the other for programming)

Building Instructions...

(Sorry, I am not selling these in kit form... I'd rather build, test and sell)

horizontal rule

Testing and Operation Instructions...
Download the Mini-Beacon User's Manual below (in PDF format... Adobe reader is required)
The web version of the manual is shown below:
The Mini-Beacon controller has a servo cable which can either be plugged into a spare channel on your Radio Control receiver (Rx) or it can simply be connected to a 5-6 volt power source.  Opposite of this servo cable lies a two pin connector (inline with board) that is used to connect your beacon LED.  The onboard output driver/transistor is capable of providing around 600mA to a connected load.  A typical 5mm LED draws 20mA while a 1 watt Luxeon emitter draws an average of 350mA.  3 sets of jumpers/pins located on the Mini-Beacon are used to either set the flash pattern (1 of 12), set the servo control function, or allow the controller to free-run.  First thing you will obviously need to do is connect an LED to the Beacon output pins (see picture above, observe polarity).  Be sure to use the proper series current limiting resistor inline (series) with one of the LED leads (typically 56-120 ohms).
There are two ways you can operate the Mini-Beacon controller.  You can either set it up so it's in "free-running" mode (apply power, and it flashes continuously until power is removed), or you can connect it up to a spare R/C receiver servo channel and control (on/off) the flashing pattern of the beacon using a stick, slider or switch on your transmitter (aka Servo Control Mode).  The Mini-Beacon has two jumpers that allow you to set these two functions (labeled "Servo Jumper" and "Free-Run" on the picture above.  Only one of these jumpers should be connected at one time. 

Servo Control Mode
If you want to be able to turn the beacon effect on & off using your R/C gear, you will need to attach the supplied push-on jumper to the pins labeled "Servo Jumper".  This allows the servo signal from your Rx to be read by the PIC.
Note: No jumper and/or short should be across the "Free-Run" pins.
Now, when you plug the Mini-Beacon into your receiver, not only does it gets its power, but it also reads the servo signal output signal from the receiver's servo channel and either turns on or off the beacon effect.  The PIC is pre-programmed to switch on at roughly 60%.  If you use a switch to control this function, you might have to reverse that channels servo function on your transmitter in order to get it to work to your satisfaction (i.e. configure on/off position of switch).  Also, be sure the R/C channel you are using has its "end-points" set to at least 100% on the transmitter.
Free-Running Mode
If you want to allow the Mini-Beacon to run all the time when ever powered up, you need to do two things (referring to picture above):
1) Disconnect any jumper/short attached to the pins labeled "Servo Jumper" if it is connected.
2) Apply a push-on jumper across the pins labeled "Free-Run"
Now, every time you power up the Mini-Beacon, it will begin flashing, and continue so as long as power is applied.  You can still plug the Mini-Beacon into your receiver for power, but the servo control function will not work.
Controlling the Mini-Beacon with your "MINI-FLASH" !You also have the cool option of controlling (on/off) your Mini-Beacon using a channel on your Mini-Flash.  This is accomplished by first setting up the Mini-Beacon so it's in free "running mode" (no jumper across "Servo Jumper", and a jumper across "Free Run" pins).  You can now take the Mini-Beacon servo/power lead and plug it directly into a channel on your "Mini-Flash" controller in order to receiver power when the Mini-Flash channel is active.  Be certain that you plug it on correctly, the black lead should connect to the  top pin on the Mini-Flash, while the red lead connects to the bottom pin on the Mini-Flash.  The white lead on the Mini-Beacon should connect to nothing (hangs down a little below Mini-Flash board). 
(Click on picture to the left for an enlargement of what the Mini-Flash programming software would look like to control the Mini-Beacon).
Now, set up a Mini-Flash channel (#1 in this example) such that all 50 events have a checkmark in every location.  Set the Servo Control for channel #1 such that it is only ON for 0-1/4 throttle ("*---").  Now, when the Mini-Flash channel is High or ON (only between 0 and 1/4 throttle), it applies power to the free-running Mini-Beacon, allowing it to flash its preset pattern.  When the Mini-Flash channel turns off, so does the Mini-Beacon.  You can then set up the Mini-Flash such that the channel events (all 50) are selected or check-marked (left to right), and then you set the servo control for the stick position you want for that channel to activate.  If you are using a switch on your transmitter to control this channel the Mini-Beacon is plugged into, simply set the servo control to "**--".
Cool or what?

Programming & Operating the "Mini-Beacon"...
The "Mini-Beacon" can be programmed to display 1 of 12 different flashing sequence patterns stored on the PIC.  To change the pattern, perform the following steps:
1) Apply power to the Mini-Beacon and be sure it is flashing its programmed pattern.
2) While the pattern is flashing, continuously short the programming jumper (two pins shown towards the top/left on drawing) with either the supplied jumper or a piece of conductive metal (coin, paper clip, screw/nail, etc...)

3) Soon after you short these pins together, you will see the LED glow constantly bright.  While it is glowing steadily, remove the short/jumper and you will see the controller quickly flash a certain number of time before continuing its rotating beacon effect.  The number of flashes seen here indicates the pattern number it is now using and displaying.  The 12 different patterns are shown below:
1)  Slow Ramp-up, Flash, Slow Ramp-down
2)  Slow Ramp-up, Double-Flash, Slow Ramp-down
3)  Slow Ramp-up, Triple Flash, Slow Ramp-down
4)  Med. Ramp-up, Flash, Med Ramp-down
5)  Med. Ramp-up, Double-Flash, Med. Ramp-down
6)  Med. Ramp-up, Triple Flash, Med. Ramp-down
7)  Moderate Ramp-up, Flash, Moderate Ramp-down
8)  Moderate Ramp-up, Double-Flash, Moderate Ramp-down
9)  Moderate Ramp-up, Triple Flash, Moderate Ramp-down
10)  Fast Ramp-up, Flash, Fast Ramp-down
11)  Fast Ramp-up, Double-Flash, Fast Ramp-down
12)  Fast Ramp-up, Triple Flash, Fast Ramp-down

4) Continue applying and removing the jumper (following steps 2-3) until you selected the pattern you like.  When you are satisfied, you are done!  Every time you now power up the controller, it will use this pattern you have selected.
NOTE: Recent Mini-Beacons I have sold also have another hidden function that allows you to quickly reset the pattern to Pattern #1, rather than having to cycle through all the patterns using the jumper/power numerous times.  With the Mini-Beacon un-powered, connect the programming jumper and then power up the Mini-Beacon.  You will see the LED glow steady and will do so until you remove power, so remove power.  Remove the jumper and re-power the Mini-Beacon.  It should now be set to program #1, regardless of its previous pattern setting.

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