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>if your cap is not big enough get a bigger one ;)
Yes, that’s the right answer.Then the crystal caps are indeed the likely culprit– the crystal may simply not run if the caps are that far off from spec. It’s likely worse than you think, because a breadboard adds quite a bit of stray capacitance, too.
I’m not entirely clear on what you’re trying to do, and what’s not working here.
– Is the AVR working correctly when it is in the Diavolino, or in the breadboard, or both?– What’s not working, or otherwise leading you to suspect a clock issue?Likely not hopeless; the FTDI chips are pretty well supported, and generally can be made to work one way or another. (I do not have the same level of confidence with respect to the leostick.)
See if you can map your adapter onto the “standard” FTDI cable pinout, to make sure of which pin is supposed to go where, and make sure that your environment is set up correctly: right port and board type and all that.>So should I be able to tell for sure that it’s working by actually testing the current through the reset pin?
Maybe. Easier to just check for continuity and that pin 1 is either high or low, respectively, when an external signal is disconnected or asserted low.>As for the capacitor, that handles the auto-reset function, doesn’t it?It’s the combination of the R and C that makes it work. :)>Is there a way that I can check the function of the auto-reset reliably?The circuit should reset when you try to program it.The “blink” sketch is loaded in a single step *on top* of the Arduino bootloader, so (if you haven’t reprogrammed it) there shouldn’t be any way for it to blink unless the bootloader is indeed active.
You might also check to be sure that the 10 k resistor and 0.1 uF cap are installed correctly and in good shape, as those are also necessary for correct function.If all else fails, contact our shop for a return– we can check for correct function and reflash it if indeed necessary.There’s no straightforward way to calculate that with the amount of information that you’ve given.
The coordinates in the horizontal direction are absolute. As I said: 3200 pixels corresponds to one complete revolution, so if you know the circumference of your egg, you can easily calculate how wide the design should be in Inkscape.In the vertical direction, the exact scaling depends upon a number of factors including the shape of the object and pen motor position. I can give you some starting points, though:– If you are printing on a sphere, put the pen motor in the top position, and the horizontal scaling is equal to the vertical scaling.– If you are printing on a chicken egg, put the pen motor in the center position (halfway between top and bottom positions), and reduce the drawing size by about 1/3 in the vertical direction. (Or, stretch it horizontally to about 1.5 X the initial width before calculating the proper horizontal size.)The LED on pin 13 is not really related to the bootloader– it just indicates that the Diavolino is “awake” and past the bootloader stage. There should be a delay between when you reset it and the first blink.
You might want to consider loading the ArduinoISP sketch onto that leostick (if possible) and try to do this the “recommended” way. ;)
Auto reset is not absolutely necessary. You can often program the device if you press the reset button at just the right moment– you should have a two second window for it to find it while trying to program.Yes to all of those– and thanks!
A few more points of interest, too:– PD7 is “designated” as a place for an extra LED, but is actually also available for hacking in any way that you like.– PD0 and PD1 go to an extra serial interface (J5). We plan to use this for serial data out, for daisy-chained displays, in the next firmware revision, but you’re also welcome to repurpose those in any way that you see fit. :)– O10 – O15 can potentially be used to drive additional LED “segments,” should that happen to come in handy.There is no such list, because pixels correspond to angles, not to inches.
For each motor, a movement of 3200 pixels corresponds to one complete revolution. If you are printing on an egg that is one inch in diameter, then 3200 pixels corresponds to 3.14 inches– in the horizontal direction. If you are printing on an egg that is 3.5 inches in diameter, then 3200 pixels corresponds to about 11 inches– in the horizontal direction. If you are printing on a ball that is 3.5 inches in diameter, then the distance scales in both the horizontal and vertical are 11 inches per 3200 pixels.If you are printing on chicken eggs, the total vertical range available to you is about 800-1000 pixels. If you want to test your range without “using up” eggs, just set your pen in high enough that it doesn’t touch the egg when in the down position, and run a test print that way.> after 5 seconds of being plugged in I smelled burning
My advice: Do not plug that thing back in until you’ve figured out what the pinout of it is, and how it *should* be connected to the Diavolino.>could you offer a better description of Note 1?
The “black” pin on the Diavolino is electrically connected to the pin next to it.>would it be easier to just bite the bullet and buy the adafruit USB->TTL ?Of course, but not necessarily quicker. ;)I don’t know what the pinout for that particular adapter is, but it’s likely not directly compatible. From the page on that site, “6 pins for 3.3V, RST, TXD, RXD, GND & 5V.”If this is the order of the pins, you’ll need to do some creative rewiring to get it to work with the Diavolino, since it expects a pinout compatible with the FTDI USB-TTL cable or the Adafruit FTDI Friend:1. (Green): RTS#2. RX3. TX4. Vcc (5 V)5. CTS6. (Black) GNDNote 1: Pin 5 (CTS) is hooked to GND on the Diavolino, so you may need to clip the “elbow” out of the right-angle header if your adapter has (one or the other) power rail there.Note 2: The ATmega328 chip requires 4.5 V when operating at 16 MHz, so you can power the Diavolino on 5 V, but not 3.3 V.It would likely work somewhat, but it will definitely have a large loss in sensitivity. The sensors send infrared light up, and look for reflections back. If it’s dark enough to look mirror-like to your eyes, it’s likely passing less than 1% of the light through, and there are two passes through it. Obviously, you’d have to try the specific material to see how well, if at all, it would work.
Well, you’ll have to drop the extra voltage somewhere. And, with components like these, you’re not going to get much efficiency, no matter what you do.
