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1  Using Arduino / Installation & Troubleshooting / Questions about the arduino bootloader. on: March 29, 2014, 02:41:08 pm
Hello, I have a question regarding the Arduino bootloader, as I'm still a little confused even after reading a bit about it.

So it's to my understanding that the bootloader is used so that you don't need external hardware to upload code to the chip. I've read that it is not necessary in all circumstances to have the bootloader when uploading Arduino code, is this true?

I know in the past I have programmed external atmega328 chips on a breadboard by attaching it to an arduino uno's RX, TX, ground, 5V, and reset pins (Oh, and the arduino had its DIP socket empty). To be honest, I don't remember if this chip had the bootloader on it or not. For this method of programming is the bootloader required?

I have also been looking at these serial USB programmers:
http://www.ebay.com/itm/10pcs-FT232RL-USB-To-Serial-Adapter-Module-USB-TO-232-Download-Cable-For-Arduino-/281234998607?pt=LH_DefaultDomain_0&hash=item417ae9854f

If I were to use one of these to program the chip, is a bootloader required?

Thanks in advance to anybody who has input!
2  Using Arduino / General Electronics / Re: My Arduino Nano decided to stop working? on: May 10, 2013, 09:06:51 pm
Alright, so I found my multimeter and tested as suggested. There did not appear to be 5V present so I suppose the diode is indeed shot.

Now I guess my question is what could have caused that to happen? It literally just happened out of nowhere while it was plugged into my computer.
3  Using Arduino / General Electronics / Re: My Arduino Nano decided to stop working? on: May 09, 2013, 09:41:20 pm
OK

Yes I saw your first post Runaway Pancake and I guess you didn't see my response where I said I wasn't sure what you were asking...

Well, given --

DVDdoug:
I'm not really sure what you're trying to say... I see the portion of the schematic your referring to but what am I supposed to do with this? Sorry...
I'm not DVDdoug, so I jumped right over that.



My apologies, I meant to put your name.

Well I am now home but I can't seem to find my multimeter anywhere... I guess we'll have to put this endeavor on hold until I find it. Unless somebody else has advice.

I'd like to thank everybody who has given me feedback so far, I really appreciate it!
4  Using Arduino / General Electronics / Re: My Arduino Nano decided to stop working? on: May 09, 2013, 08:35:27 pm
Plug your Nano into the USB
Get out your voltmeter.
If you don't measure 5V with the positive lead on "5V" and the negative lead on one of the Nano's "Gnd" terminals then that aforementioned diode is b-a-d.

Okay thank you. I will check that right when I get home and I'll tell you the results
5  Using Arduino / General Electronics / Re: My Arduino Nano decided to stop working? on: May 09, 2013, 08:25:44 pm
Am I here?
Like I said in Reply #2:
Look to see if there is 5V at the 5V pin when it's plugged in to the USB connector.
If there's not then that diode is shot.

Yes I saw your first post Runaway Pancake and I guess you didn't see my response where I said I wasn't sure what you were asking...

Can you please explain what you mean? I'm sorry, I guess I don't know enough about this to know what you're telling me to do. Do you mean with like a multimeter or something?
6  Using Arduino / General Electronics / Re: My Arduino Nano decided to stop working? on: May 09, 2013, 07:55:51 pm
Shouldn't the resistors I have drop the current enough to prevent that kind of damage?
No, I didn't see the resistors.  my bad.

I'd still check to see if the diode is damaged, that's the gate between the regulator/5V pin and Vusb.

Okay, I will. However, do you know where it might be located? because if it is on the underside I have no way to get to it since my nano is directly soldered in place.
7  Using Arduino / General Electronics / Re: My Arduino Nano decided to stop working? on: May 09, 2013, 07:41:24 pm
There is a diode between Vusb and 5V.

http://arduino.cc/en/uploads/Main/ArduinoNano30Schematic.pdf

I don't know what that IC does, but if it doesn't limit the current to those LEDs (I'm betting on, it doesn't) then you may have drawn enough current to damage that diode.

While connected to USB, I would measure the voltage across both sides of the diode.

Shouldn't the resistors I have drop the current enough to prevent that kind of damage? I don't know if you can see them but there are 8 of them (one for each row on the screen) right up against the nano.

Oh and the IC is just a shift register.
8  Using Arduino / General Electronics / Re: My Arduino Nano decided to stop working? on: May 09, 2013, 07:37:01 pm
DVDdoug:

I'm not really sure what you're trying to say... I see the portion of the schematic your referring to but what am I supposed to do with this? Sorry...

ebird97:

well the main portion of the arduino must still be functional if it can still run when powered by the 9v battery, so what exactly would I be looking for when probing?
9  Using Arduino / General Electronics / My Arduino Nano decided to stop working? on: May 09, 2013, 06:18:10 pm
Hello,

So I have this little 8x8 led matrix game powered by an arduino Nano here:


The little thing was working just fine and dandy for quite some time until a couple of days ago the whole USB computer interface stopped working entirely. I was just in the middle of using it hooked up to my computer when it just stopped powering on. I unplugged it and replugged it in a few times to see if I could get it to work with no luck.

 If I power it on by using a 9v battery (like in the next picture) it is able to function. The led on the arduino lights up and the LED matrix lights up.


now, it should do the exact same thing when I plug it into my computer by USB. However, when I do that now nothing happens at all. The led doesn't light up and my computer doesn't even seem to recognize it:


But it definitely isn't the computer or the cable's fault, because I have an identical Nano that when plugged into the same computer with the same cable it powers up fine:


This would lead me to believe that it is probably a hardware issue on the arduino, but I checked out the physical plug and compared to my spare arduino nano. The connector looks to be identical and doesn't look damaged in any way.

So this means that it isn't the being caused by a fault in the actual circuit, it isn't the computer's/cable's fault, it isn't the plug's fault, but what could it be?

Thanks in advance to anybody who has any advice!


10  Using Arduino / Microcontrollers / Re: Programming an Atmega328 using an Arduino Uno on: May 07, 2013, 07:28:06 am
Thanks for all of the help, guys. I found out that the problem was as many of you suggested the caps on the crystal were too high. They were actually .1uF caps that somehow managed to find themselves into a bag in my drawer labeled 22pF. I should really be more careful next time I do some cleaning up...

I just want to say I really appreciate how helpful the arduino community is. I've had many silly questions like this (and I'm sure many to come...) that you guys have happily answered for me.

Thanks!
11  Using Arduino / Microcontrollers / Re: Programming an Atmega328 using an Arduino Uno on: May 06, 2013, 07:40:18 pm
First thing, never connect a LED directly to an output pin and power or ground.  You should always have at least a 220 ohm or higher resistor in series with the LED.  Even though it may seem to work with no harm, you could be damaging the ATmega328P chip by drawing too much current through the port.

Which method of programming are you using?  Are you removing the m328p from the Uno, or have a separate m328p to program with?



Oh, I didn't realize it really mattered that much to put the led directly to the pin. I usually do use a resistor but I guess I didn't realize it was this important. I'll do that from now on, thank you!
As for your question, this was a chip taken directly out of my current Uno.
12  Using Arduino / Microcontrollers / Re: Programming an Atmega328 using an Arduino Uno on: May 06, 2013, 05:48:02 pm
Okay, I went ahead and actually reassembled the circuit yet again on a different breadbaord (again with no luck :\). Here is a snapshot of it:



Hopefully it's not too hard to see, I got the best picture I could. This circuit doesn't incorporate the connections needed to program the chip, this is only to power it. Essentially all it has is the oscillator connected to the clock pins with two caps going to ground, an led connected to ground/pin 13, and power going to the + and - pins. The red wire going off screen is connected to the arduino uno 5v pin and the blue wire goes to the ground pin. The arduino is then connected to my PC via usb.

So does anybody know why this wouldn't power on?
13  Using Arduino / Microcontrollers / Programming an Atmega328 using an Arduino Uno on: May 05, 2013, 07:11:34 pm
Hello all, I have a question about programming an Atmega328 chip on a breadboard using an Arduino Uno. So I'm using this little tutorial here: http://arduino.cc/en/Tutorial/ArduinoToBreadboard

Now I know that the tutorial specifically mentions this is for the Duemilanove and not the Uno, but just here me out!

A little while ago, maybe less than a month ago, I tried using this tutorial to create a breadboarded atmega328 (taken out of my Uno) to be programmed using my Arduino Uno. Now the weird thing is that even though it says the Uno doesn't work for this method, I was able to get it to work. I was able to compile and upload code using the Uno that I had hooked up to it (as directed in the tutorial) and it ran properly. Unfortunately I inevitably disassembled this circuit so I could continue using my Uno normally.

Now flashforward to a couple of nights ago:
I once again attempted to use the same setup to make a functioning breadboarded atmega328. Unfortunately, this time I had no luck. If I hooked up my Uno the same way and it just gave me an error in the IDE saying something about a sync error. Now here's probably where the problem really lies: If I hook up a preprogrammed Atmega328 (In this case one just running the standard pin 13 LED blink program) and set it up using an external crystal, regulated 5v power supply, and an led on pin 13, it won't even run. Nothing. However, If I take that same chip and put it back into my Uno, it will blink the built in led on pin 13 just fine. So this leads me to believe it really isn't the Uno's fault, nor is it the chip's fault... but then what is the problem!?

Another thing I'd like to mention is that over these past few nights I have disassembled and reassembled the circuit several times to see if I had perhaps missed something when I had wired it the night before, but I still have had no luck.

So does anybody have thoughts as to what the problem could be? If anybody has any clue what could be the problem here, it would be great if you could give some advice, thanks in advance!

Oh, one last thing: would pictures of my project be of assistance to anybody in helping with my problem? I'd be happy to take them if they would be help.
14  General Category / General Discussion / Re: Where can I get jacks/connectors like this? on: May 05, 2013, 08:26:49 am
hello, i have seen those things at a hardware shop near my place have you tried that? also i normally see those things from other devices such as the lipo battery head. just an advice, do you need the connectors? can you just solder it straight to the board?

No, I haven't tried a hardware store. I guess I wouldn't have thought to look there. Personally I would prefer to buy online if possible, but if I have no luck elsewhere I'll give the hardware store a shot.

Also to answer your last question, I'm looking for a matching set so that it can be easily removed and reconnected.
15  General Category / General Discussion / Where can I get jacks/connectors like this? on: May 05, 2013, 08:15:14 am
The other day my bedside clock crapped out, so naturally I decided to crack it open and look inside. Inside I saw these little connector things:



(I'm talking about the little white connectors, as well as the one that still has wires attached to it)

Now I know I have seen these before so that can't be all that uncommon... does anybody know where I might be able to find something like these for my small scale hobby projects?? I've looked across ebay with no success unfortunately. To be honest, it really doesn't need to be exactly like that. All that I am really looking for is a connector with prongs that can easily be inserted into a through-hole circuit board.

If anybody knows where I might find something like this, please let me know.

Thanks!
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