It is a friends birthday tomorrow and like the typical bloke type I forget to get her something special. And its the end of the month with big bills arriving so an extravagant shopping expedition is not possible. So yesterday I had the idea of returning to my childhood solution which was to glue some junk together and blag the 'I made it specially for you' excuse
Because I'm lazy the I used a spare mobile phone charger rated at 5.5 Volts and 800 mA. This way I don't need regulation components or battery boxes or even batteries. I used a Atmel8 with Arduino boot loader burnt on it because you can buy them for about £1 and I have a box of them for this sort of project. I programmed it in a standard Arduino and then swapped it over to the custom PCB. I also used a bit of code I wrote for a Knight Rider type LED scanner that uses software PWM as there were not enough built in PWM channels for that project. The PCB was milled on my Proxxon MF70 that I recently converted.
So in summary everything on this project was from the junk / spares box!
I am using the free version of Eagle so am limited to about 3 by 4 inches on PCB size. The Proxxon Miller also has a limited area for larger work.
My soldering leaves a lot to be desired, maybe I'll ask for a good soldering iron for my next birthday
The bare minimum, A crystal, Reset tied to +ve and the power supply is taken care of as it will be powered from a 5 Volt mobile phone charger wall plug unit.
The layout was a squeeze!
This is the finished gift, should look good hung on a wall or illuminating the inside of a bin