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We actually fabricate the target boards in quantities of 500 or more, so it’s somewhere between low and high volume.I’d recommend OSH Park for small quantities– their quality is impeccable, and the pricing is quite good.
Yes, these were 1-2 Hz kind of motion. It’s visible to the eye if your gaze is fixed– but (like with most POV devices) you won’t see it if you follow the electronics with your eyes. If you make a shorter pendulum (so that it will have a shorter period), you might want to turn up the oscillation frequency.
Yes, that looks like the likely explanation; the standard Arduino ethernet shield can draw 150 mA on its own, so you probably need around 200 mA total capacity.I don’t know of any device that can burn that much power and can fit in the TO-92 location provided. If you pull a full 500 mA, then you would be asking the regulator would be to “burn up” (12 V – 5 V) * 500 mA = 3.5 W of power as heat– more than actually goes to power the device, and much more than a TO-92 package can normally handle. In situations like this, one normally wants to use a switching regulator that will convert the input power, rather than just burning up the majority of it.
As far as similarly-sized linear regulators go, the L4931CZ50-AP will fit in the location provided, and handle 250 mA, but will be thermally limited and likely will not work. At 200 mA, you’d be dissipating 1.4 W as heat. The thermal resistance of that device is 200 degrees C/W (the *worst* I’ve ever seen in a TO-92!), so at 1.4 degrees, it would operate internally at 280 degrees C above ambient– well above its rating of 125 C.If you wanted to use the L4931CZ50-AP at 200 mA, one solution would be to provide it with a lower input voltage, allowing it to dissipate much less heat. Assuming 25 C ambient, you’d need to keep the thermal dissipation to 0.5 W, for a 100 degree rise. 0.5 W = 0.2 A * 2.5 V, so you’d want no more than 7.5 V input. To get there, you could drop from 12V to 7.5 V– a drop of at least 4.5 V –with a zener diode. For example, the 1N5340BG (a 6 V zener) might be a good choice.(This is very similar to the last example in our article about zener diodes, here: http://www.evilmadscientist.com/2012/basics-introduction-to-zener-diodes/ )So, there’s no easy, simple solution. It might be worth mounting an off-board 7805 (possibly with a heat sink), mounting a 7805 with extension leads, or using the zener trick, but none of these is particularly appealing. You could also make things a lot easier by reducing the input voltage, for example by using an external regulator to step the voltage down.*At the moment* it is working perfectly, with a couple of asterisks. We’ll be contacting you offline about it.
In the Finder, from the Go menu, select “Go to Folder…” and enter the following:/Applications/Inkscape.app/Contents/Resources/extensions
Well, it was worth asking. ;)
One way or the other, we’ll get you taken care of– I’m just hoping that we can understand the failure mode, too.We did receive the board, and found that several LEDs had failed– either not lighting up or lighting up, but somehow connecting two of the LED lines together. We swapped those out, and it seemed okay, but on letting it run a little longer, we’ve found that a few of the others are now flickering or otherwise. And, I must say that we have _never_ seen anything like this before. (The Bulbdials at our shop are running fine after years…)
We can keep replacing the LEDs until we’ve got them all, but I’m absolutely lacking any kind of explanation about what could have caused this. Is there anything “unusual” that you might have exposed the circuit to? (I don’t imagine there is, but again, I’d really like to get to the bottom of this.) Can you say what kind of soldering iron you use? The other solder joints look good, but I am curious if there could have been some electrical damage.IIRC, the otherwise unused I/O pins are tristated at turn-on, and have floating values that can fluctuate, which is what you are seeing. To use one as an output, you’ll need to set it to be an output first, and then set what value you want it to have.
We use one of the other I/O pins (B3) as the digital output to control the Eggbot engraver attachment, and have found that it’s typically at ~2V at turn-on. If you’d like to see how it works, open up the Eggbot software (eggbot.py) within the Inkscape Extensions folder, and look through the code. The command to initialize B3, and set it to high output is as follows:PD,B,3,0 # Set pin D3 direction (output)PO,B,3,1 # Set pin D3 value (high)To set it low again,PO,B,3,0This isn’t so different from the pin direction and pin value commands that one uses in Arduino. However, they are sent as serial commands to the EBB, rather than being compiled into the firmware.Hi idreamincode,
I suspect that you’re asking about the Alpha Clock Five, not the Bulbdial. ;)There’s no obligation whatsoever to use it as a clock. You can feed serial data to the clock using a USB-TTL cable, or another Arduino, or use the available spare I/O pins any way that you like. The current version of Alpha Clock Five has 9 (if i counted correctly) spare I/O pins that can be used as inputs, not counting the two pins that go to the second serial port.I hope that this answers your question; if not, please let me know how I can help. :DIt might be fair to say that the complexity comes not from any particular operation, but from the number of different ways to approach the problem. To me, it’s much easier to program an AVR than to format an RPi, but each of us comes with different experience. If you’d like to attempt it yourself, I’ll do my best to help. You’ll need (at a minimum):
* An AVR ISP programmer (which could be an Arduino running the Arduino as ISP sketch) or a stand-alone programmer.* A cable (6-pin DIL ribbon cable) to connect the programmer to the Octolively board (or any other target board that you’d prefer).* The AVR-GCC toolchain installed on your computer. The easiest way to do this is through (for example) WinAVR (on windows) or AVR Crosspack (for Mac).The process of programming a new chip is, generally speaking, not for 3 year olds.
You’ll need a computer, a programmer, and a “target board” — a board that provides a place to put the chip (that you’re going to program) and provides connections to the programming interface. Usually, you would use some sort of AVR ISP programmer (such as the USBtinyISP, the AVR ISP Mk II, or an arduino, pre-programmed with the ArduinoISP sketch) as the programming interface, and the Octolively board itself can be used as the target board. You do not need a bootloader; that’s used for a different type of programming. In addition to that hardware, you’ll also need to install some software on your computer (including AVR-GCC and avrdude) that can be used to compile and upload the new program.
An example project that might point you in the right direction is here: http://www.evilmadscientist.com/2012/blink-an-led-with-an-avr/
You might also want to consider purchasing a pre-programmed microcontroller to save a few steps.
My best guess is that there’s a damaged LED that’s not acting like an LED. But yes, please contact our shop directly about returning it for examination and repair.
Awesome, thanks!
If it’s sensitive to capacitance, it could be that there’s an issue with the capacitors on the board– in which case a small change in external capacitance could cause a large shift. Check to make sure that all of the caps are in the right places, with the right orientation (for the big electrolytic), not cracked, and soldered cleanly. And again, see if you can stimulate a failure by tapping or prodding any particular component. Try to use something like a plastic pen to tap them, to minimize the capacitive issues.
Yes, I’ve just downloaded a fresh copy and verified that it’s the right one. If it is the right one, and it’s installed correctly, you should see File > Examples > Time > Examples > TimeRTC
