We will be closed on November 25, 2021 and November 26, 2021 in observance of the Thanksgiving holiday. We will resume normal operations on November 29, 2021. Wishing you a safe and happy holiday from all your friends at SparkFun!


Receive a free SparkFun USB Thumb Drive with every order this weekend. Details.


Member Since: November 19, 2009

Country: United States

  • Was initially very interested in this given the price and what it did, but given its Apple-like lock-in I'm not going to even buy a single one to play with. The Carambola is a far better, open platform IMHO. I have 6 of them and they're superb, and cheaper than the imp, and no silly cloud-based lock-in so you can be held to ransom later.


  • Nice little kit. One thing puzzles me about the schematic though - the LEDs are connected directly to the AVR pins. The AVR runs 3v3 and the LED Vf is 2v1. There are no current limiting resistors. Having looked at the source code each digit is turned on for 1ms in turn during the interrupt routine. I presume you're relying on the AVR's current limiting to stop the segments getting more than their 20mA Ifmax? Not sure how that's going to do the AVR in terms of reliability as I'm not sure it's rated to take that sort of punishment continuously? Or have I missed that bit of the AVR data sheet? :))
    In any event though, absolutely love the simplicity of this design. That's what electronics should be about - minimum parts, maximum elegance!

No public wish lists :(