As I reported a while back, I killed one of my Netduinos. I recently successfully removed the dead chip, but now I can seem to find any available ( both Mouser and Digikey report out of stock and won't have any 'till after the first of the year). I believe that I have been able to verify that the board is still viable so I wanted to "glue" a new cpu chip on this guy to test my smd skills. Any one know where I can locate a at91sam7x512?

I built my own imediately after getting my 'duino and FEZ domino. I had the box in my scrap box and added the breadboard and a 5volt regulator. I have a chassis plug on the back of the box to connect VIN.

I just got my Netduino, what I don't understand is the purpose of the little colorful stamp/piece of paper. Also is there a summary of the netduino sdk anywhere. I am an old guy who is used to having a reference other than the code.

EDITTED---
I purchased an AdaFruit Protoshield and that's all build and piggybacking my Netduino. What's not clear to me is how the various buttons on the shield relate to the Netduino. For example, I have two LEDs on the protoshield and two buttons. How are these addressable through code (given that the Netduino only has one of each)?

EDITTED AGAIN--
What I'd like to do as a next step is control a 5v motor, attached to the shield, and have its speed adjusted with a photoresister. Pretty basic, eh? :-) I'm not clear on how/where I'd hook up the motor to the shield (which pins) and also where the photresistor fits into the picture (on the shield in series with the motor, presumably, but what voltages should I use)?

And again
Thanks.

Mark

I hope you don't mind I didn't quote your entire post since I am going to start by answering the easy parts . But here goes:

One of the buttons (the one labeled RESET) is tied to the reset on your board and that is all it can do for you.
The other button and the two LEDs are not assigned to any function instead they are tied to ground on one end and the other is to a pad you can route to any of the DIO ports. The LEDS have a current limiting resister on them so they are safe. You just have to make sure you define the DIOs used with the LEDs as outputports and the button as an input port with a pullup. You can view the schematic here: http://www.ladyada.n...v5schematic.png

Hey,

I'm looking for male PCB mount connectors and their female counterparts (leads). I prefer the connectors have only one way to connect, so you can't switch poles by accident.

I've seen leads like these on LiPo batteries, but I can't seem to find anything useful on RS Online or Mouser when searching for "JST connector".

The PCB connector part looks something like the white connectors on this shield.

I'm EU based so I prefer a supplier like Mouser or RS Online that ships easily to Belgium. Any other EU based shop is good too!

Thanks a lot!

Niels R.

I think this is what you are looking for if the ones in your second picture will work. http://www.sparkfun....roducts_id=8232

What is the best programming environment for you?
Ideas of what to specify:
-Music
-People around you (# of, type of)
-Food/Drinks
-Noise level (cars, people, etc...)
-Computer specs
-anything else

For me:
music - Metal as loud as I can stand it; maybe some dark metal like Cruxshadows, Without Tempation ...
People - Barnie my conure. She counts as a person doesn't she!
Food/Drinks - The days of Twinkies and Orange soda are way behind of me, I have to watch my weight so no food, Coffee or Diet Coke to drink
Noise level - I have no tolerance for that stuff thats why I have the music and over the ears headset.
Computer specs - Two 24" wide screens, one for code, one for design/spec/videos.

I found that when using the tactile miniswitches, http://www.sparkfun.com/products/97 , if I add a 0.1 mF cap from the signal line to gnd and enable the pull-up resistor cleans up the interupts just fine.

The biggest reason why AREF is not connected to 3.3V internally is because the SAM7X512 chip doesn't support that natively. The AVR chip on the Arduino has an "internal AREF" as an optional integrated feature.

The other reasons we didn't just wire 3.3V to AREF and skip the AREF pin: [a] we wanted people to be aware that the Netduino was a 3.3V device and to be careful not to put 5V into the analog pins when used in analog mode; [b] we wanted to maintain the chip's capability of having an AREF which varies from 2.7V to 3.3V...for our customers who are using Netduinos for commercial engineering prototypes.

That said, I've chatted with engineering about potentially adding an "internal AREF" option in hardware on a future Netduino board revision. It would be a cool feature to have, for sure. For now, connect the AREF pin header to the 3.3V pin header with a jumper wire when using analog inputs.

Chris

Personally, I like it the way it is. I was not confused by the AREF at all, my problem was that initially I did not pay attention to the fact that the shield had wired the pots to 5 vdc. Then in my haste to compensate I over drove the A/Ds by attaching AREF to 5V. Through this I learned a lot about the Netduino and its relationship to the Arduino. I won't make the same mistake again and hope that my original post will help others.
I conform strongly to the concept of modularity, therefore I feel that if the shield uses A/Ds then it is responsible for supplying the AREF. It may not matter much in the case of a connected shield, but having the A/D source supply the AREF is one sure way of insuring that the A/D's are reading accurately.
So my vote would be, If you are going to add "internal AREF" it should be done via a jumper on the Netduino and the jumper should be left off by default.
I plan to make all my projects supply the AREF for accuracy, so don't break my projects please.

Just a quick note for anyone who may want to use the SparkFun Electronics Joystick Shield, DEV-09760 http://www.sparkfun....oducts_id=9760. I bought mine to use for experiments with my Netduino. While it worked fine after I built it, I did find the there were problems with the analog reading for the X and Y pot on the joystick. Following the information I saw here I had added a patch wire from the 3.3 Vdc to Vref. But noticed that the center readings were 66% of full scale. which meant that the min to center would have twice the resolution of the center to max. I am a software engineer not a hardware engineer so it took me a full half hour to realize that the problem was that the pots were biased using 5 Vdc. I change the jumper for Vref to the 5 V source. This did a find job of centering the signal, but the max values were very unstable. I guess I was over driving the A/D. So I cut the trace from 5 V to the joystick and added a wire from 3.3 to the joystick and Vref. Now every thing works just fine. See the attachment.

After the modification to make the Joystick work with the Netduino the next step was to add some extra circuitry to support my next experiment. I wanted to control a servo or two with the joystick I also wanted some indication that the program was in control . So I added two 3 pin connectors for the servos and a LED. Here is an update to the schematic for the shield just incase someone want to critique it.

The problem is that when a pwm period and duration are the same the output is high. Period is the rising edge to rising edge time of the output wave form. While duration is the length of the high time of the period. So period should be 1/frequency and duration should be (duty_cycle * period) where duty cycle is some value < 1. Also if I remember correctly, period is in microseconds so:

Try

  var period = (uint)(1000000 / frequency); 
  pwm.SetPulse(period, period/2); 
 

I used the same buzzer and I just checked my code and the period is in microseconds like I remembered.

klotz,

Sorry, that's a bug in the Netduino firmware. The AnalogInputs work great--but if you open more than one at a time there's a glitch which causes the Netduino to hang.

You can just erase the program on your Netduino (it takes about 10 seconds). See here:
http://forums.netdui...indpost__p__216

We have an update which fixes the AnalogInput bug scheduled for Monday (in 2 days).

Chris

Thanks for the reference on erase. I had no idea that it could be done that way. The only answer I could find was to totaly erase the board as I described. I will try that next time.

Well that means that at least one of my projects will be on hold til monday.
Is there a list of open items somewhere so I don't have to spend time finding them on my own?
If so, is there also a list of what is going to be fixed and when?
I

When I execute this snippet on the Netduino, it hangs on the xVar.Read(). After that, I can still see Neduino-neduino on in my devices list, but I am not able to access it from the debuger or MFDeploy.exe.

namespace Bug
{
    public class Program
    {
        public static void Main()
        {
            // write your code here
            int xValue = 0;
            int yValue = 0;

            AnalogInput xvar = new AnalogInput(Pins.GPIO_PIN_A0);
            AnalogInput yvar = new AnalogInput(Pins.GPIO_PIN_A1);

            xvar.SetRange(0, 0xffff);
            yvar.SetRange(0, 0xFFFF);

            while (true)
            {
                yValue = yvar.Read();
                xValue = xvar.Read(); //Debugger hangs here and never recovers.
            }


        }

    }
}

So far the only remedial action I have found is to totally erase the Neduino and reflash it.

1. Am I doing something wrong in the code?

2. Is there a safer/better recovery than totally erasing the Netduino?

Help.

As soon as I get the all-clear from our users that the new AnalogInput code in the v4.1.0.2 firmware patch is working well for them... It tested out well here, but I'm being extra cautious before I post a tutorial.

The tutorial should work well with the original firmware as well (since the patch only addresses using multiple AnalogInputs at once).

Chris

The new version is working for me so far. I am using it with the SparkFun Joystick shield. http://www.sparkfun....oducts_id=9760. This is the one I was having problems with on Sat.
Thanks for the update!

I just got my netduino and I'm starting to try to get analog input and I always get 0 when I read my pin(A0). Do you see anything I did wrong?

My setup looks like this

3.3->AREF

A0->Photo Resistor->GND

public class Program
    {
        public static void Main()
        {
            // write your code here
            InterruptPort tester = new InterruptPort(Pins.GPIO_PIN_A0, false, Port.ResistorMode.Disabled, Port.InterruptMode.InterruptEdgeBoth);
            tester.Dispose();

            AnalogInput apin0 = new AnalogInput(Pins.GPIO_PIN_A0);
            apin0.SetRange(0, 100);

            int test = 0;
            while (true)
            {
                Thread.Sleep(250);
                test = apin0.Read();
                Debug.Print("Test: " + test);
            }

        }

    }

You would need another resister to 3.3Vdc to develop a voltage divider. There is no pull-up in the An-in.

My guess: CadSoft Eagle (?)

Yep, I use Cadsoft Eagle. But don't ask me for help with it. I am just returning to doing hardware after 40 years and am trying to catch up.I just kindof hack away with Eagle until something works.

I'm confused would it look like
AREF+3.3v->resistor(what resistance?)->ground?->photo resistor->A0?

First you need to know what the resistance of the photo resister is. Mine was 25k full dark.
Second you need to decide if you want it to pull-up or pull-down. I used mine in a pull-up.
Then choose a resitance to give you some kind of reasonable current limit, I chose 10K since I just wanted to play.
So using the attached schematic, I put the photoresister in a R1, a 10k in R2, you can try it either way and pick the one you like.

Thank you for explaining now i understand. Time to play with my netduino!

The fun is just begining
The next thing you want to do is check out the projects page.

Unfortunately, the Atmel chip is about a $20 chip (of course unless it is purchased in quantity). I'd say digikey is your best bet.

Just be lucky it isn't a ~$150 chip

In either case logic dictates that I order a new Netduino. $20 + shipping and handling and frustration of removing the old and adding a new > 34.95 + shipping and handling.

I unfortunately plugged my shield in off key without noticing it and when I powered my Netduino it failed to connect. I tried to find the software reason it wouldn't connect rather than what could be wrong with hardware. Once I notice the shield was not plugged in correctly, I disconnected the power removed the shield and allowed the duino to cool. TOO LATED Well live and learn. From now on, I won't power-up without checking the connections. Oh well now I have to order a new one Just had to get that off my chest.

I ALWAYS triple check my connections. So far, I have not fried even a single component.

I have gotten quite close though Just ask my temp sensor that had a backwards pinout to the dumb datasheet....

I guess I shouldn't try to work on my board with distractions. Just did not notice the pins that were not in their sockets.

Hi klotz,

No fun at all. It sounds like it got fried, but you may want to try erasing the Netduino (using the ERASE) pad and seeing if you can reprogram it. It's probably fried--but there's a small possibility of recovery...

Chris

P.S. Reverse power protection and a resettable fuse are built into the Netduino. And the odd pin spacing for shields helps keep pins in the right place. But while Netduino is designed to take a certain amount of abuse, it is possible to fry a pin (or in more extreme cases, to fry a whole Netduino). Most users will be fine--but it makes me sad to see one get electrocuted...

He's dead Chris.
No amount of protection can survive an unattentive user. Just got to excited about testing my two ethernet shields and didn't notice I had plugged it in wrong. The Seeeduino shield is wider than most so it is not as easy to see the pins if you don't pick it up and inspect it.
And of course I was convince I had checked it so I let it cook while I trouble shot the failure to connect. The Atmel was way hot, and I can't get any response from it at all except a very bad smell and lots of heat.
(Kind of reminds me of like Washington D.C. or Springfield, IL)
I'll mount this one on the wall with a note "CHECK THE SHIELD" hanging from it.
That's what overconfindence will get you.

R.I.P.

But now you have a perfect board to practice SMD reworking (assuming you've burnt just the micro)

Now there's a good suggestion.Since I am normally a software guy, where would be the best place to get a replacement Atmel? Digikey is asking $20+shipping handling tax. Almost the price of a new Netduino.
Any suggestion where else I should look?

Use a PWM. You can then control the brightness by changing the duty cycle (duration). I would reference the articles in this forum but you can't search for PWM or LED because of the search rules

What are the differences between SPI and the other thing that uses TX and RX? I understand that SPI has a clock so the shift register (lets use that as an example) knows when to read the other pin for a HIGH or LOW. but then how does the TX and RX communicate? how does it know when to get the data? Are they both Serial types of communication or not? Any info is appreciated, links are good too. Thanks!

I don't know how much time you have to read stuff, and we could spend a lot of time asking and answering questions so I thought that it may be helpful to supply you with a link to the Wikki page that describes SPI. This may be way more than you wanted to know but there are nuances to using SPI that are not immediately apparent and which many of us take for granted. So here is the Wikki link ( and yes I read it and it is a good description on Jan 2, 2010 You know how Wikkipedia can be )
http://en.wikipedia....l_Interface_Bus