Introduction: An LED Persistance of Vision Name Badge
This Instructable shows a name badge that I have built for my daughter.
I have seen the Defcon badges, and thought they were cool. Why cant my kids have one as well - but specially built for them?
So here you go - A simple badge that uses a PIC 16F88, and a handful of LEDs, and flashes your child's name in lights when they shake it, or push a button.
I have left space on the PCB that I designed so that it can support an accelerometer. It isn't in this version because I have to order the parts. This one is created using the bits I had in the garage!
Step 1: Etch Up a Board - Make It Decorative
The first step it to create the PCB using your favourite PCB package.
You could download my PCB file, but it probably wont work unless your child is named Sian! Just in case people ask, I have included it as a PDF file.
In Sians case, I created a PCB layout - and made a decorative fill as a background - I think it turned out pretty well!
Here is a photo of Caties board having finished the etching process - I just have to clean the etch resist off the board, and mount the components.
Step 2: Mount the Components, and Program the Micro
Having made the PCB, you then get to mount the parts, and then program the microprocessor.
As with all of my projects, there is a programming header mounted on the PCB. I simply connect my home made PIC programmer to it, and I can program the board.
If you want to make your own programmer, then I can heartily recommend the open source one at openprog.altervista.org/OP_eng.html. I have built it, and it works beautifully. Alternately, you can simply purchase one of the many programmers on eBay. They also work fine!
Here is a copy of the hex file that says Sian, and the asm file. Also included is the schematic.
You will notice pads for an optional accelerometer and associated components. When these arrive, I will be able to add code to allow the display to always be the right way around irrespective of the direction the board is being shaken!
You will also notice a 5 pin header on the back of the board - that is for a programmer that I use for development.
Here is a detailed list of components that are used on the PCB
U1 - 16F88 Microprocessor
R1-R7 - 1k0
R8,R9 - 10k0
R10 - 10k0
C1 - 0.001uF
Sw1 - Pushbutton Switch
D1-D7 - SMD LED (Red)
D8 - 1N4004 Diode
J5 - 5 pin programming header
B1 - CR2032 Battery + Through Hole Holder
Optional accelerometer components
U2 - MMA7260Q Accelerometer
R11-R13 - 1k0
C2-C4 - 0.1uF
C5 - 10uF 16V