The Beetle is like a cut-down Leonardo, a 16MHz ATmega32u4. For your $7.90, you do not get a voltage regulator, or a reset button. However, you do get a small board with a wearable-friendly layout, USB connection, and full “normal” Arduino IDE support (none of this ATtiny messing around). If I had one wish for it, it would be for it to have an on-board reset button to save me the trouble of jumpering when things go bad. Like they do. Around me.
I’ve used a couple of them now and I’m really liking the balance of very small size and full-scale features. It’s shown below with an Adafruit 16-pixel ring.
Anyway, it seemed worth noting and sharing the link.
I Just got my own in yesterday. They are TINY!, I just wish they were skinny like the trinket, but they have enough pins for everything i want to do, with the added benefit of having more memory!
I also have a collection of random Arduino from different kickstarter. I have an addiction to collect them even if i never use them. You can also try a Lily Twinkle from Sparkgap. but they require a special pogo board to program them. but those are smaller then a dime, but they run attiny85
@Nevada_Smith : There are LOTS of “Arduino” boards like this one, that all work with the Arduino software – most will work fine with FastLED, too. $8 is about the cheapest you’ll find, more or less. Less than that and you’re in “build your own from raw chips and components” land.
Some of my favorites are:
Arduino Nano (cheap, same CPU as Arduino Uno)
Arduino Uno and Leonardo (accept ‘shields’)
Teensy 3.0 / 3.1 (small, wicked fast, lots of RAM, great support)
Digistump DigiX (wifi!)
Do you have a particular project that you’re looking at, or just learning at this point?
@Hien_Pham : I like the form factor of the Trinket. Other than that, the Trinket makes me a little crazy. Low memory, very quirky Arduino IDE integration, plus you have to push the physical button every time you want to reload new code (or at least, that’s the way it was a few months ago when last I used it). And slower code execution due to the lack of a MULtiply instruction on the chip (not even counting the 8MHz “half speed” version).
And I agree: part of what makes the Beetle awesome is that it works like the (well-supported) Leonardo, but is sized and priced more like the Trinket.
I’m interested to see what the “Trinket Pro” that Adafruit has mentioned will be like. My hope is that it’s actually sort of like the Beetle…
I got a couple of these and they worked great, at first… then they stopped going into bootloader mode. It’s like I could only upload code one time and then I’m stuck. There doesn’t seem to be any sort of reset button. I was able to get it to accept code by plugging it into my USB port at EXACTLY the right time… but once the code started running, I can’t get it back into bootloader mode. There’s a blue onboard LED that blinked so nicely and indicated the mode and now the LED doesn’t come on at all. I can’t find any documentation on this board, and it happened to both of them so I’m hoping it’s something I’m doing wrong…
I had a couple of beetles do this, and while there’s no reset button, but you can perform the ‘reset’ function by momentarily touching a wire to GND and to the RESET pin on the ICSP connector on the bottom of the board.
There’s a picture here: http://www.dfrobot.com/wiki/index.php/File:Beetle_back.png
I believe that the ICSP pad with the square shape is GND and the one “above” it in the picture is the RESET pad (that’s the pad closest to the “I” in “ICSP” that’s silkscreened on there. Grounding the RESET line should kick the board back into bootloader mode.
I had a related problem that’s worth sharing: If you use a super-power-saving library, like “Narcoleptic”, on a ATmega32u4 -based Arduino board (e.g. the Beetle, or a Leonardo), the board goes ‘deaf’ to USB while it’s doing the deep-sleep thing… and that includes being deaf to re-programming via USB! Frustrating! I kept having to jumper GND to RESET, which is how I learned that this worked.
Ultimately, to prevent locking myself out of being able to reprogram the Beetle (without jumpering the pads), I started using this ‘delay’ function in lieu of Narcoleptic.delay():
void LowPowerDelay( int ms)
{
// if we’re in the first ten seconds, use regular delay
// so we’re not locked out of USB re-programming
if( millis() < 10000) {
delay(ms);
}else {
// otherwise, use super-low-power delay
Narcoleptic.delay(ms);
}
Of course, now I forget and maybe you have to jumper from VCC (+5) to RESET to make it reset into bootloader mode. Doing the wrong one won’t damage the board; I just forget now which it is, grounding the RESET line, or driving it high. If you get it working, please let me know!
(And don’t I feel sheepish…)
I believe it was the VCC line. I got it to reset one time and go into bootloader mode for just a second, which of course wasn’t long enough for me to actually get more code to upload. Now the board is getting really hot if I just leave it plugged in and running… which may be a problem since it’s running a costume and I have a 2 hour performance in said costume tonight.
Do I try and change back to the other beetle board? Sub in a flora? Or just wrap this thing in tinfoil and hope for the best? Do the beetle boards regularly get hot or did I blow a fuse or something?
Ouch. Mine never got hot. I’d swap in something known-good, either another beetle or a flora, or a nano, or whatever you have handy.
(Thank you on the VCC info. I still feel sheepish for offering the wrong advice there…)
Also, if I recall correctly (this is known-faulty, see above), the Flora is only 8 MHz, not 16 Mhz, so there may or may not be timing issues with your animation code, depending on how it’s written, etc.
I’ve had mine lock me out of the bootloader before. It required me to do a lot of quick timing. I end up loading up a blank code, and when i plug it into the computer i would press the upload to the micro from the IDE. it takes a few tries, but i was able to enter in a blank code and able to get the beetle working again.
In the pictures above with the neopixel ring. You appear to be using a coin cell holder for two CR2032 3V batteries. That would make the total voltage 6v. I know I may have asked this before, but is that ok? DFR says not to use 6v or it will damage board. Just wondering cause I really would like to use that setup but am afraid to try.
