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Ornament '09 preview

Here's a picture of our November project, an AVR ATTINY13A-based blinking Christmas card/ornament. It'll be available at Seeed Studio assembled, and as a kit, well under $20 (shipped).

We got the PCBs yesterday and tested the design today. We were expecting regular green PCBs, but got black, which isn't a very traditional Christmas color... Would you prefer red, green, black, or another color?

There's some urgency with this project - in order to deliver anywhere close to the Holidays we have to order a number of these now, instead of the usual preorder. That's a bit daunting. If you have a suggestion for quantity, or would just like to buy one, please let us know so we can get a handle on how many to order.

The how-to article should be out in the next week, maybe on Thursday as usual, but hopefully on Tuesday.
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Re: Ornament '09 preview

Reply #1
I'd probably buy one. I'd vote for either a green or maybe a blue board.

Re: Ornament '09 preview

Reply #2
yep, i would probably pick one up as well.
and yes green is good for this.

Hope theres an RGB star at the top of that tree :)

Re: Ornament '09 preview

Reply #3
Great idea ... sounds like a neat little present. :)

I'd take 5 assembled ones (and maybe a few kits), preferring red or green PCBs.
If they come in black or blue, I will take them, too ...

P.S. to me the top of the tree looks more like a hole than an RGB LED ;)
... but the RGB LED idea might lead to a last minute change of the project? o.O

Re: Ornament '09 preview

Reply #4
You're right, it's a big VIA for hanging it in a tree like an ornament, weighting a balloon bouquet, etc. Eric at Seeed said he might use one as a bicycle light.

RGB LED - That's absolutely in my next card (Valentines, Halloween, or Christmas, I guess, want an LED beating heart to give your sweetie? I give one to mine every year!). It would need three PWM channels, this project only has 2 free pins because AVRs use a four pin programming interface :)
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Re: Ornament '09 preview

Reply #5
[quote author="ian"]
It would need three PWM channels, this project only has 2 free pins because AVRs use a four pin programming interface :)
[/quote]

I was wondering, why are the LEDs (apparently) connected to both PWM pins?

I was thinking of cutting the trace across the top to have two groups of LEDs to blink, but then noticed I'd have nowhere to connect them.

Also, would it harm anything to have your serial output pin also control some LEDs?

Re: Ornament '09 preview

Reply #6
Quote
I was wondering, why are the LEDs (apparently) connected to both PWM pins?
They aren't actually PWM pins, they're just IO pins that I named 'PWM' because software PWM comes out. I connected both because they are the only free pins and I wanted to make sure there wasn't a stupid mistake like one pin being input only, etc.

Quote
Also, would it harm anything to have your serial output pin also control some LEDs?
Depends. I only know from my experience with PIC, but if the load is too much (transistor base sinks too much current) then it slows the programming lines and you cant get a clean signal. I had this problem when i reversed engineered the Esquire magazine E-ink cover. This project is up against a tight deadline, so I didn't want to take the chance this time, but in the future I plan to work that out.

I'm thinking MSP430 for the next design. I believe they have a uC with very low power capacitive touch sensing for the button. I'd also like to do the RGB led thing, maybe adjust the color using three (cap touch) mixer buttons? It would be good to have the extra I/O pins come to vias around the edge of the cards, and hopefully all future cards have bootloaders.

I think this is a fun thing to do for Christmas, Valentines, and Halloween. I make my sweetie a new pulsating LED heart every year.
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