"hard" experience: cant get diavolino working!, I just checked and 2nd check but nothing, I noticed the atmega gets realy(hurting!) hot! very fast so I decided to get some help to check(I cant belive cant getting work the Meggy Jr its s "little" more complicated to assembly and its working)so , could some one contact me by email or in the forum to make a third check(I have the pieces to check in breadboard, almost assembly everything on Diavolino, but have take appart the atmega and crystal).

Thanks in advance.


Erick Nava Aldana.

If the AVR is getting hot, fast, that usually means that it's plugged in backwards, or that you've otherwise applied power backwards. So... TURN IT OFF right away, and then check your polarities. Make sure that the half-moon end of the chip is at the end furthest from the power jack.

Now, you haven't said what your configuration is, which makes it pretty hard for me to guess how you might have hooked it up.


So, whichever way it is, check that you're applying power the right way-- should be +5 V at "VCC" and 0 V at ground. Backwards battery connection? If using an adapter, make sure that it's center positive and DC, not AC.

Next, check that you're only applying power from one source. USB-TTL, OR battery, OR, power input jack, not more than one.

Finally, check that your power source is an appropriate one. If it's battery, 3 alkaline AA or AAA cells give 4.5 V, not much else is appropriate. 4 NiMH cells give 4.8 volts, that's also OK. BUT, make sure that they're connected the right way! Plug in power supplies need to be regulated, 5 V, unless you've got the onboard regulator installed, and in that case you need to make sure that the regulator jumper is not installed.

Still cant Diavolino works! : ( I checked all you say but all seems ok, I use Dievolino Kit with Battery Holder, 3 NiMh 1800 Batteries and double checked connections but nothig, Its there some other way to check?

If it possible I will send you some pictures at night.

Thanks!

There is no reason to assume that it will work with 3 NiMH batteries. As I said, the chip requires 4.5-5.5 V while operating at 16 MHz. Three 1.2 V batteries give a total of 3.6 V. I have heard occasional reports of success despite this, but you certainly can't rely on it.

In any case, if it's still getting hot, you've still got something backwards or otherwise short circuited. Maybe you have the battery wires backwards?

I buyed all except Atmega Crystal and FTDI Breackout board that recommend this link http://itp.nyu.edu/physcomp/Tutorials/ArduinoBreadboard but I dont know if its safe to do the test this way, so I dont do anything until some one say its safe, just to check the Atmega away all other components, what you think?, I test some components with the Multimeter(Im not a electrician guy, maybe need some other tool or method to test, just tested continuity and voltage pass) but there its no current after +/- battery connector on the pcb, so I will check the batteries, as you say, I asume it will work but does not check the total current in the battery holder, the led does not seem to work, but dont smell as burned one, thats why I plan to test the chip on breadboard(couse Im afraid to fry the Duemilanove Board if try to test there).

>I buyed all except Atmega Crystal and FTDI Breackout board that recommend this link

I'm afraid that I don't understand what you're saying. Perhaps you can clarify.

Are you saying that you don't have the crystal oscillator for the Diavolino? I can tell you that you *need* to install the crystal and its two little capacitors in the right locations for the Diavolino to be responsive, but missing those couldn't explain why it's getting hot.

Again, you've got something backwards or short-circuited, and the only way for you to tell what is to closely examine the board yourself.

sorry about confussion, yes I have the crystal , and I remember the two black marked(on right place) and the three other capacitors, two resistor(cant remember valuse at this time but I buy all the kit from you store) 0 ohms resistors and reset button and LED(this seems not work, maybe shortcircuited but does not smell like one-I have other 3mm and 1.8 from Led Sample Kit, could replace with one right?), then when I look does not work, I buy all other parts mentioned on the link from a local store just to make a breadboard test, taked appart the atmega and the crystal from Diavolino, but I dont feel safe to do the test directly on the Duemilanove Board.

So I take a in deep look at night to de Diavolino and take some picture to share with you, it this ok?

Thanks for you fast response.

I'm really not sure what you're trying to do here. I initially thought that you were trying to solve a problem on the Diavolino. But now it sounds like you're trying to do some kinds of tests with a breadboard and Duemilanove. I'm not sure what you mean you would do with those.

In any case, all of these are beside the point. If your chip gets hot that means that either a power source or component is backwards, or that there's a short circuit somewhere. You don't need a breadboard or Duemilanove or FTDI cable to debug this.

As you say I try to "debug" why my Diavolino does not work, that why "think" to test the chip away the PCB to determine if its the chip or something on the PCB or soldering work, but at thist time need to put all my effors in the Meggy Jr then after getting the Meggy working again I will back to check all in Diavolino.

Many thanks for all your Help.

I don't see how you would test the soldering on the Diavolino or the chip by performing tests elsewhere.

You have a major, basic problem with the wiring on the Diavolino; testing parts off of the board is probably not going to help you solve this problem, particularly if you have to desolder parts to do it.