Happy Birthday Project

[monkeybiter]

Recently it was my son's 17th birthday. I decided it was about time I produced something finished from my time absorbing hobby, so I set about designing an amusing novelty present for him.
The original idea was to embed a device inside a sacrificial book [hardback] which would start to make a noise at a predetermined time [school break time] causing him to find it within his school bag, and upon opening it would display 'amusing' messages on an lcd.
For various reasons the project morphed into effectively a fat musical birthday card. I used an old 'learn Chinese' book with nearly every page glued together and hollowed out. I used a 16f468, a 2x16 lcd, piezo, microswitch and a 9v battery. Opening the book releases the microswitch which is in series with the battery. On powering up the pic displays 'happy birthday' etc. and plays 'happy birthday to you' on the piezo using timer1 interrupts.
Not much of a project, but it was fun and I think my son appreciated it [and I finished it!]. With a little more time it might have been a little more interactive, and the aesthetics might have been a little better, but I am encouraged and next time I might just do better...

 

[tcmtech]

Thats a hundred times better than any present I ever got!
Nicely done. If that much thought went into it, it was worth it!

 

[monkeybiter]

It was gluing 550 pages of that bloody book together that was the worst! If I ever do that again I will use an easier method

 

[Gayan Soyza]

This time also do you need to place the circuit inside a book?

 

[monkeybiter]

The original idea was an lcd badge [with circuit inside breast pocket] but I thought he probably wouldn't have worn it for long.. considering some of the jokey messages I would have coded.

 

[Gayan Soyza]

MADLAB did some battery powered nice projects.See whether you can find one.

MadLab Electronic Kits

 

[flat5]

I, for one, would like to see the details of of your hard work.
schematic, pictures if you already have them.
Just to see what you've done.

 

[monkeybiter]

I'll pop the schematic on, very simple though. If I do take a photo' you must bear in mind I was rushing to meet the deadline so the presentation is not rather poor.
What I did find interesting was working out the timer1 values to play the tune, i.e. finding the written music, finding out each note's frequency and duration etc. I came across a useful web-based tool that many current students might easily utilise in their projects :- Google

 

[jbeng]

I came across a useful web-based tool that many current students might easily utilise in their projects :- Google

Too bad most of them never think of that... Congrats on completing your project!

Jeff

 

[monkeybiter]

Here is the schematic.. nothing special or clever. The switch between the battery and the regulator is normally held in the open state by the book's cover. When the book is opened the switch closes the circuit and the pic boots. It uses the internal oscillator. I changed the original plan of using a piezo to using a louder 8Ω PC speaker.

 

[Gayan Soyza]

Ok nice then you need at least 9V battery

Whats that connector in the RB0?What for?

But I like if move to a 14 pin PIC & make your design more compact.ex: PIC16F630 (1$).
Actually you don't need a regulator, powering from 4 (AA) or 4(AAA) via a diode will be fine.

 

[monkeybiter]

Gayan, firstly thanks for the interesting link in your earlier post. I see there is a badge on that site [a badge was my first idea]
I did use a 9v pp9 battery.
I originally intended to have a button to add a little interactivity to the device but lack of time left that, and some other features, unimplemented.
The 16f648 was chosen because I intended to do more and also I had one.
I'm not totally happy with the outcome, but I am encouraged for the future.

And thanks for your comments.