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#65431 i2c PowerUp

Posted by TechnoGuy on 28 July 2016 - 10:34 PM in Netduino 3

I just wanted to follow up on my June 29th query.

 

This was resolved for me by incorporating the workaround (strobe the SDA line before initializing I2C) posted by KiwiDev over on this forum thread:  i2c strange behaviour

 

In his reply, KiwiDev refers back to an August 2013 forum thread which discusses the basis for the workaround:  Netduino 2 and the Adafruit BMP085 Barometer (I2C)

 

So in short I can now get both of my HTU21D modules (SparkFun & Adafruit versions) to work with both of my Netduino boards (Netduino Plus 2 & Netduino 3 Wi-Fi).

 

As mentioned in my earlier post, there are implementation differences between the two modules.

  • The SparkFun module is the simpler of the two, incorporating two pull up resistors and a capacitor.
  • In contrast, the Adafruit module incorporates two BSS138 FETs, a MIC5225 LDO regulator, four pull up resistors & a couple of capacitors.

I guess that the relative sophistication of the Adafruit design makes it more sensitive to the starting condition of the SDA line when I2C is initialized.




#65307 Netduino 3 Ethernet Static IP Issues

Posted by TechnoGuy on 06 July 2016 - 01:45 AM in Netduino 3

Please see these issues I logged against the Netduino.IP repository on Github back in November 2015.

 

https://github.com/n...duino.IP/issues

 

  • Problems with EnableStaticDns() & EnableDynamicDns() methods in NetworkInterface class
  • EnableDhcp() not implemented in NetworkInterface class
  • EnableStaticIP() not implemented in NetworkInterface class

With Netduino 3 there was a move towards the implementation of lwIP (i.e. "Lightweight Internet Protocol").  I believe this was done in anticipation of what would be coming out in NETMF 4.4.  Anyway, the above methods DO work on Netduino Plus 2 and DON'T work on Netduino 3.  I'm not sure if they're things that should have been implemented by the board developer or if they're part of NETMF 4.4.

 

Anyway, if they're things that are important to you, please visit the issue list on Github and add your comments / reaction (vote up) the issues.

 

See also this topic thread on the Netduino Forums:

http://forums.netdui...it-doesnt-work/




#65276 i2c PowerUp

Posted by TechnoGuy on 30 June 2016 - 06:53 AM in Netduino 3

Mark, thanks for the reference to that article.  I will have a good look at it.

 

I'm pretty certain both my HTU21D breakouts (SparkFun & Adafruit versions) have internal pull up resistors.

 

Ian




#65269 i2c PowerUp

Posted by TechnoGuy on 30 June 2016 - 12:03 AM in Netduino 3

Hi Roy,

 

I have a different but related issue.

 

I have two HTU21D sensor modules.

  • I got one (uses the HTU21D chip) from SparkFun (part #12064) about 2 1/2 years ago and.  They don't carry it anymore & have replaced it with a module which uses an Si7021 sensor instead (part #13763).
  • I got a second one (uses the HTU21D-F chip) from Adafruit (part #1899) more recently.  It's my understanding that an HTU21D-F is just an HTU21D plus a 5 cent PTFE filter.

The problem I have is that I can only get the SparkFun module to work with the Netduino; I can't get the Adafruit one to work.  It fails when I try to do a Soft Reset.

 

I have been successful in getting both modules to work with an Arduino type MCU (Teensy 3.1), using the exact same code.

 

I read your comments with interest and have tried connecting VIn on the HTU21D-F to 5V rather than to 3.3V.  It didn't make a difference for me.

 

Physically, there is a difference between the modules:

  • The SparkFun module has only 4 pins (VIn, GND, SCL, SDA)
  • The Adafruit module has 5 pins (all of the above + the 3.3V VOut)

I guess LadyAda implemented her module a little differently, to incorporate the 3.3 V voltage regulator.  Anyway, I'm at a loss to understand what's so different between the modules that one will work while the other won't.  Hoping you might have some insights on this...

 

Maybe you could post your initialization code?




#65251 How to communicate to your PC using the serial port?

Posted by TechnoGuy on 24 June 2016 - 08:35 AM in Netduino 3

Hi, if you're expecting to be able to do serial communication between your Netduino & your PC using the USB cable that you use to power your Netduino / program it, it won't work.  While you can do this using an Arduino or a Particle Photon, it won't work for a Netduino.

 

Please see this forum thread from a few years ago for some background:

http://forums.netdui...d-the-netduino/

 

Nevyn asks if you're using a USB to serial cable.  He's talking about a USB to TTL cable - a special type of USB cable that contains an embedded chip which converts the voltages / signalling between what the PC speaks (i.e. differential USB signalling @ 5 V) to what the Netduino requires (i.e. TTL at 3.3 V).

 

You can find these cables many places.  Adafruit carries two such cables - one which uses a Prolific PL2303 chip and another one which uses an FTDI FT232RL chip.  I have used both with my Netduino and have been successful in transferring data between it and my PC.  SparkFun also has a cable like this.  They're about $10 US (the high end one that Adafruit sells is $17).  You'll find items like this on eBay; beware that there have been issues with counterfeit chips in the ones you can find on eBay.

 

USB to TTL Serial Cable - Debug / Console Cable for Raspberry Pi
 
FTDI Serial TTL-232 USB Cable
 
USB to TTL Serial Cable

 

With regard to your code...

 

On the Netduino:

  • On a superficial level the code you've written for your Netduino looks okay.
  • You're attempting to use the COM1 UART on the Netduino.
  • Be aware that this designates digital pins 0 & 1 (RX & TX respectively) on the Netduino.
  • It is NOT the Netduino's USB port.

On the PC:

  • The code you've posted is written to utilize the COM1 port - that's a real physical hardware RS232 port on many PCs (older ones).  Newer PCs frequently don't have such a port.
  • If you get one of the above-mentioned cables and plug it in, it will expose itself as something called a Virtual COM Port (you may need to install some drivers the first time round).
  • After this has been done, you will need to go into Device Manager on the PC to look up which COM port number has been assigned.  One way to do this is (Windows 7 assumed) to go into Control Panel, choose Device Manager, and then expand the Ports node of the device tree.  It's not unusual to see a Virtual COM port with a higher number (i.e. COM6, COM8).
  • Once you've figured out which port has been exposed - update your PC code to use that port #.

You can find a nice diagram of the Netduino here.  You can see which pins are used to implement the COM ports (4 of them).

 

http://forums.netdui...&attach_id=2376

 

Hope this is useful to you.




#64904 Support for Micro SD Card > 2 GB

Posted by TechnoGuy on 19 February 2016 - 09:07 PM in General Discussion

I wound up purchasing some no name (lesser name "Aura") 2 GB Micro SD cards on eBay back in September 2015.  I bought 3 of them for a total of $8.16 USD and I think that actually included the shipping as well.  They all work but I suspect they've undergone less testing than / may not be as reliable as the brand name alternatives.

 

With regard to support for modern Micro SD cards (i.e. SDHC / SDXC - those having capacities greater than 2 GB) on the Netduino, I do not at this point expect that to happen anytime soon.  From what I've read, it was limitations in the early implementations of the .NET Micro Framework (i.e. software, not hardware).  I don't know if perhaps they've addressed it in NETMF 4.4 but it's unclear whether NETMF 4.4 will ever be made available on the Netduino.




#64875 Web server, socket, reading buffer data?

Posted by TechnoGuy on 11 February 2016 - 12:56 AM in Netduino 3

Hello Brian,

 

I'm intending this as a quick suggestion - I haven't looked at your code thoroughly.

 

What stands out to me in your code is your use of the "WebRequest" class rather than the "HttpWebRequest" class.

 

Would you please have a look at THIS forum posting, and response #8 in particular, which talks about the WebRequest class (which is abstract), and the HttpWebRequest class (which is an implementation of the WebRequest class).  Your solution may lie partially in switching from the abstract class to the derived one.  I believe that - when you look at the properties of the derived class, you'll see one or 2 extra items that need to be setup in order for the request to work.

 

That forum posting again, is:  http://forums.netdui...ng-to-database/

 

Also please take a look at Cuno Pfister's code (referenced in an earlier reply to the same forum posting) for a good programming example.

 

If this doesn't help you, please post again & I'll try to take a closer look at things.

 

Regards,

Ian




#64848 Introducing Netduino 3 Ethernet

Posted by TechnoGuy on 04 February 2016 - 02:29 AM in Netduino 3

Hello - a useful approach for you to take would be to look into the code you have that DOES work on the Netduino 3 WiFi & Netduino Plus 2 and DOES NOT work on the Netduino 3 Ethernet and extract from that a SMALL piece of code that DEMONSTRATES the problem (complete with output from both).  Post your sample code here on the forums.  Consider starting a new forum thread rather than tacking onto ages old threads that are no longer current.

 

In addition, please post details of your development environment & what Netduino & .NET Micro Framework SDKs you have installed.  You'll find them listed on the Downloads page.  Visual Studio version?  .NET MF version?  Netduino SDK version?

 

With the above, members of the community are probably in a better position to help youfigure out what the problem is.

 

I can tell you that the Netduino 3 boards make use of a different TCP/IP protocol stack than what was on the Netduino Plus 2.  I think some functionality works differently.  With regard to the Netduino 3 WiFi & Netduino 3 Ethernet, they have DIFFERENT networking chips.  Consequently, I think there are some TCP/IP stack implementation differences that have arisen from that as well.

 

You posted in another thread about where you could return your device.  I think that would be to the company that you purchased it from, if it's within their return period.




#64785 Netduino 3 Wifi - Not seen in MFDeploy after Update to 4.3.2.2

Posted by TechnoGuy on 21 January 2016 - 04:59 PM in Netduino 3

To answer your questions:

 

Netduino 3 WiFi firmware version:

As of the current date, the latest version of the firmware for this device is 4.3.2.2

 

MFDeploy - where do I get it?

There are instructions on the Netduino downloads page on how to setup your development environment.  It says to install 4 things, in a specific order:

  1. MS Visual Studio
  2. .NET Micro Framework SDK
  3. .NET MF plug-in
  4. Netduino SDK

If you've done all of the above, then you'll find MFDeploy by choosing the following from your Start menu (assumes Windows 7) doing either of the following:

  • Start -> All Programs -> Microsoft .NET Micro Framework 4.3 -> .NET Micro Framework Deploy Tool (MFDeploy)
  • Start -> All Programs -> Microsoft .NET Micro Framework 4.3 -> Tools
Pinging...TinyCLR
Yes, that's what you will see...

 

Setting Up WiFi Credentials on the Netduino 3 WiFi

In MFDeploy do the following:

  1. Change device type to USB & make sure your Netduino shows up (mine shows Netduino3_Netduino)
  2. Do a ping just to make sure it's responding; you should see the ack discussed above.
  3. Select Target -> Connect from the menu (you should see a message "Connecting to Netduino3_Netduino...   Connected"
  4. Select Target -> Configuration -> Network from the menu

At this point you should have a dialog box with the heading "Network Configuration" and there will be enterable fields for numerous items.  You'll see a Wireless Configuration group box and all the stuff you need to setup (Authentication, Encryption, Radio, Pass phrase, SSID).

 

Before doing anything, make sure your MAC address hasn't reverted to a default value.  Consult the MAC address label on the underside of your Netduino & re-enter it if necessary.

 

Please see if this all works for you...




#64690 Ip Address Netduino 3 Ethernet

Posted by TechnoGuy on 29 December 2015 - 01:57 AM in Netduino 3

The original poster of this question started several threads about it.

 

Please see this other thread for details.

 

http://forums.netdui...it-doesnt-work/

 

He wanted specifically to be able to set a static IP address at run time.  If you don't need to do that (i.e. you're okay with setting it beforehand) you can just do so using the MFDeploy tool.




#64667 Forum was away from home for a while-- what happened?

Posted by TechnoGuy on 26 December 2015 - 03:58 PM in General Discussion

I think it would be useful if one or two of the longer term / committed supporters of the platform could be granted some limited administrative capabilities for the website / for the forums.  I would support the idea that Nevyn could be one of them.

 

On a related note, I think it would be neat if community members were able to assist in the development / maintenance of the firmware(s) for the different boards.  For example, there appear to be some issues with the networking stacks in the recent Netduino 3 boards.  With the source code for these over on GitHub, maybe we could be contributing fixes that could be pulled into a potential new release?




#64666 Netduino Projects on Hackster

Posted by TechnoGuy on 26 December 2015 - 03:49 PM in General Discussion

Great idea!  Thanks for doing this.  I will definitely check out what's going on there & see if I have something to contribute...




#64626 Downgrade netduino3 ethernet

Posted by TechnoGuy on 08 December 2015 - 11:05 AM in Netduino 3

The network adapters in the Netduino 3 WiFi & Netduino 3 Ethernet boards are different from what is in the Netduino Plus 2.

 

  • Netduino 3 Ethernet:  Asix AX88796CLF MAC/PHY chip (10/100 Mbit/s)
  • Netduino 3 WiFi:  Texas Instruments CC3100 (supports up to 802.11n & supports SSL)
  • Netduino Plus 2:  ENC28J60 (only 10 Mbit/s)

Because of this I believe it was necessary for new support to be implemented for the networking hardware in the Netduino 3 boards.

 

In addition, there's been an initiative (coming from the .NET Micro Framework team) to move from the original networking stack to something called Lightweight IP (LWIP).  I believe that much of that has been incorporated into the drivers for the network adapters in the new boards.

 

Anyway, several people (myself included) have noticed that certain network-related things which used to work on the Netduino Plus 2 don't work / don't work properly / don't work the same with the Netduino 3 boards (check other forum postings).

 

There is a GitHub repository (see the link below) which contains the source code for the new network stack.  I would suggest that you could log issues against the repository for the problems that you're seeing.  Maybe we can all work together to get a good work list created.  It's actually possible for members of our community to contribute fixes to that repository.

 

Netduino IP GitHub Repository




#64519 netduino Servo controller

Posted by TechnoGuy on 15 November 2015 - 07:42 PM in Netduino 3

Try this:

using System.Threading;
using Microsoft.SPOT.Hardware;
using SecretLabs.NETMF.Hardware.Netduino;

/*
September 28, 2015:

    I found this code at this URL:  https://jamessdixon.wordpress.com/category/netduino/

    All the servo examples (the ones I examined) on the Netduino forums & even on the GHI codeshare space are written for the pre NETMF 4.2/4.3 PWM implementation.
    There's a guy named Chris Seto who wrote something & posted it to GHI & Netduino.  It's OLD.  He's not back with a revised version.
*/

namespace Tryout_Servo
{
    public class Program
    {
        private const uint TILT_SERVO_STRAIGHT = 1500;
        private const uint TILT_SERVO_MAX_UP = 2000;
        private const uint TILT_SERVO_MAX_DOWN = 1000;

        private const uint PAN_SERVO_STRAIGHT = 1500;
        private const uint PAN_SERVO_MAX_LEFT = 750;
        private const uint PAN_SERVO_MAX_RIGHT = 2250;

        private static PWM _tiltServo;
        private static PWM _panServo;
        private static uint _tiltServoCurrentPosition = 0;
        private static uint _panServoCurrentPosition = 0;

        public static void Main()
        {
            SetupServos();
            InputPort button = new InputPort(Pins.ONBOARD_BTN, false, Port.ResistorMode.Disabled);

            while (true)
                if (button.Read())
                    MoveServo();
        }

        private static void SetupServos()
        {
            uint period = 20000;
            _tiltServoCurrentPosition = TILT_SERVO_STRAIGHT;
            _panServoCurrentPosition = PAN_SERVO_STRAIGHT;

            _panServo = new PWM(PWMChannels.PWM_PIN_D5, period, _panServoCurrentPosition, PWM.ScaleFactor.Microseconds, false);
            _panServo.Start();
        }

        private static void MoveServo()
        {
            _panServo.Duration = PAN_SERVO_MAX_LEFT;
            Thread.Sleep(2000);

            _panServo.Duration = PAN_SERVO_MAX_RIGHT;
            Thread.Sleep(2000);

            _panServo.Duration = PAN_SERVO_STRAIGHT;
            Thread.Sleep(2000);


        }
    }
}




#64443 N3 Ethernet - it doesn't work

Posted by TechnoGuy on 03 November 2015 - 06:38 PM in Netduino 3

You are correct - there does not appear to be a solution at the present time:

 

There does NOT appear to be a programmatic way to setup Static IP (or for that matter to switch things back to Dynamic IP) on a Netduino 3 board using the current implementation of Netduino.IP.

 

On your board (Netduino 3 Ethernet) and on my board (Netduino 3 Wi-Fi) we both have the Netduino.IP 1.0.0 assemblies.

 

I did see a mention elsewhere in the forums about Netduino.IP 1.0.1 (a revised version, in which it was suggested that numerous problems were fixed).  That appeared to be in relation to backporting Netduino.IP onto a Netduino Plus 2.  I don't believe it can be loaded onto a Netduino 3 (because of differences in the networking hardware).  My impressions of Netduino.IP at this time is very dim; I would NOT recommend loading that assembly onto a Netduino Plus 2 until the board's creator can weigh in on things.

 

As a short term workaround (think "months") I think it would be worthwhile for you to investigate configuring your board's networking settings manually, using the MFDeploy tool that's found in the Microsoft .NET Micro Framework 4.3 program group (off the programs menu).  If you use that method you should be able to setup static IP once & NOT have to write code to do it.




#64440 N3 Ethernet - it doesn't work

Posted by TechnoGuy on 03 November 2015 - 07:42 AM in Netduino 3

Please see 3 issues (#5, #6 & #7) that I've logged for Netduino.IP in the netduino repository on GitHub:

 

https://github.com/n...duino.IP/issues

 

The problem is in the NetworkInterface class (from the Microsoft.SPOT.Net.NetworkInformation namespace).  You can view it here:

 

https://github.com/n...orkInterface.cs

 

A simple inspection of the code reveals that:

  • The methods EnableStaticIP() & EnableDhcp() are NOT implemented.
  • The EnableStaticDns() & EnableDynamicDns() methods ARE implemented, but an underlying method, UpdateConfiguration() (that they both call), is not implemented.

As I have indicated in my reports, these 4 methods:

  • WORK on a Netduino Plus 2 (with the original TCP/IP stack)
  • DO NOT work on a Netduino 3 Wi-Fi (with the Netduino.IP TCP/IP stack)

Claudio indicates that his experience is similar for the Netduino 3 Ethernet.




#64427 N3 Ethernet - it doesn't work

Posted by TechnoGuy on 02 November 2015 - 08:19 AM in Netduino 3

Okay so you have the Netduino 3 Ethernet board then, and you have the 4.3.2.3 firmware (the current version for that board).

 

Questions:

  • What is the error message you're seeing when you attempt to compile/run your code?
  • Where does it fail?
  • What does it say?
  • Is it a compile time error or a runtime error?

 

Could you also tell me what version of an assembly called Netduino.IP is installed on your Netduino 3 Ethernet (actually I think there will be 3 separate assemblies, prefixed with Netduino.IP).

 

You will see a bunch of assemblies listed in the Visual Studio Output window when you deploy your program to the Netduino (also happens as part of a debugging session).  Somewhere in the list you'll see something similar to the following:

 

Assembly: Netduino.IP (1.0.0.0)
Assembly: Netduino.IP.Interop (1.0.0.0)
Assembly: Netduino.IP.LinkLayers.CC3100 (1.0.0.0)

 

Probably the first 2 lines will have the same names & the 3rd will have a different name.  Please tell me what the version numbers are for each of these assemblies.  I think it might be 1.0.0.0 or possibly 1.0.1.x.  Please tell me also what the NAME of the 3rd assembly is.

 

You mentioned that your code works on a Netduino Plus 2 that you already have???  I bet if you look at that, you will NOT have the Netduino.IP assemblies on that board.  There's a separate download for that (Netduino.IP Technical Preview for Netduino Plus 2) - I would suggest NOT loading it onto that board at this time.  It's apparent (to me) that there are bugs in the current implementation of Netduino.IP...

 

I expect it may take weeks if not a couple of months for those to be addressed.  There's a new release of the .NET Micro Framework that just came out (4.4).  I imagine that the Netduino.IP bugs will be addressed if/when support for NETMF 4.4 comes out for Netduino.




#64425 N3 Ethernet - it doesn't work

Posted by TechnoGuy on 01 November 2015 - 10:47 PM in Netduino 3

Hi Claudio,

 

I'm not a VB programmer.  But I did try your code in VB and then I tried something equivalent in C#.

 

This is a summary of things I noticed:

 

Visual Basic Version:

I get a compile time error message "could not find library 'Microsoft.VisualBasic.dll'" (even though my project DOES include a reference to the Microsoft.VisualBasic assembly.  It shows up with the following properties when I view it:

  • Runtime Version :  v4.0.30319
  • Version:  1.0.0.0 (also seems a bit ODD)

 

QUESTIONS:

  1. Is THAT what you are seeing?  You weren't very specific in what you indicated above.  Could you please TRY to post exactly what you're seeing and on which line of code it fails.
  2. What PARTICULAR version of Netduino 3 do you have?  WiFi or Ethernet?
  3. Please look up the firmware version as well.  You can use a tool MFDeploy for that...

 

FYI - Even though you're playing around with DNS addresses, there is no place in your code where you're actually attempting to set them in place.  You need to make a call to Interf.EnableStaticDNS() to do that...

 

C# Version:

I CAN compile & run the program.

 

On a Netduino 3 WiFi, calls to the following all FAIL (for me) with a System.NotImplementedException:

Interf.EnableStaticIP(....)

Interf.EnableStaticDNS(...)

Interf.EnableDhcp()

Interf.EnableDynamicDns()

 

On a Netduino Plus 2 the calls all WORK.

 

I have asked another user to check if this happens for him as well.

 

FYI - There are differences in the networking hardware & the networking stacks between Netduino 2 & Netduino 3.  I suspect these problems stem from that.  But it's too early to say for sure.

 

I'll aim to post an update in 1-2 days.  But in the meantime could you please answer my question above?




#64411 How to interface and measure a capacitive sensor?

Posted by TechnoGuy on 30 October 2015 - 06:55 PM in General Discussion

Just following up on my initial response.  As I mentioned in that reply I believe you've got hold of technology which is at a base level, something which requires additional hardware support to bring it up to an application level.  I guess this offers lots of options in regards to how exactly to do that - i.e. what capabilities to expose & the choice of application level interface to utilize.

 

I also mentioned in my previous comments that I felt a company like SparkFun Electronics (or like your Sainsmart in the UK) might be the ones to engineer the necessary hardware support / bring things up to an application level.  I just did a quick search for "SparkFun + Weather"; here's one of their offerings, which is at the application level.  This is just for the sake of comparison & it's not meant as an endorsement of their product.

 

SparkFun Weather Meter

 

I do have one of their temperature & humidity sensors though; it's a little expensive for what it does, but it is an example of what I'm talking about.  A company called Measurement Specialties (located in France, I think) produces a chip with temperature & humidity measurement capabilities, along with a published interface (implemented using I2C).  SparkFun has taken the chip and mounted it on a PCB, breaking out all the pins & adding in all the required passive components.  They're bringing it up to application level - where "Joe Hobbyist" (i.e. a regular guy like me) can use it.  In addition, they've gone to the trouble to create a library and example code (aimed at Arduino users) for exercising it.  I developed a corresponding library for NETMF so that I could use it with Netduino.

 

SparkFun HTU21D Sensor Breakout

 

Anyway, I think you've done a lot of the hard work to bring your particular device up to application level and you're just having to make some design decisions on how to expose the functionality.  FWIW - I'm impressed with what you describe.

 

NB #1

I did try to view the Fritzing diagram you created; I get stuck at a Log In prompt for something called Atlassian Stash.  Don't really know what that's all about.

 

NB #2

With regard to data sheets, it's better to just post a link to where it can be found on the manufacturer's website than to try to post the datasheet itself (what you wound up doing).




#64409 More Digital I/O

Posted by TechnoGuy on 30 October 2015 - 06:36 AM in Netduino 3

Hi Greg,

 

You're talking about using SPI - the Serial Peripheral Interface.  That's an interface where you can connect up multiple slave devices in a bus-type configuration.

 

For example you'd use the Netduino as MASTER (controller) and you could have (say) 3 devices as SLAVES.

 

To hook everything together, you'd make the connections as follows:

  • Connect MOSI (Digital 11) on Netduino to the MOSI pins on each of the slaves  "Master Output / Slave Input"
  • Connect MISO (Digital 12) on Netduino to the MISO pins on each of the slaves  "Master Input / Slave Output"
  • Connect SPCK (Digital 13) on Netduino to the clock pins on each of the slaves  "SPI Clock"
  • Connect power & ground as well

Then you'd need to use 1 additional Digital Pin on the Netduino as "Slave Select" (SS) for EACH of the 3 slaves.  You'd connect a separate wire from the Netduino to EACH of the 3 slaves.  On the SPI devices that I have, the corresponding pin on the slave is marked "CS" (chip select).

 

For "Slave Select", you can just use any digital pin (on the Netduino) that isn't already being used for something else.  There is not a specific pin to be used.  I have seen in the Arduino world that they have suggested pins to be used for different things - e.g. SD Card Reader, TFT Display, etc.  That's just a convention.  It's basically to avoid conflicts when stacking ready-made shields & to reduce the need to have to go into canned code & customize values.

 

I found an interesting SPI & I2C tutorial on Youtube the other day that was created by Pete Dokter of SparkFun Electronics.  He's very knowledgeable on these things.  You might want to check it out.

 

SparkFun According to Pete:  SPI & I2C

 

Lastly, I've found that the there are sometimes alternative names used on devices (both slaves & masters) for the pins.  I've seen "DOUT" used (for example) as an alternative name for MOSI and "DIN" as an alternate name for "MISO".  There's a good conversion table on Wikipedia, here.

 

Good luck.




#64402 SD card not working on N+ 4.2 RC3

Posted by TechnoGuy on 29 October 2015 - 06:16 PM in Beta Firmware and Drivers

Hi - You're resurrecting a 3-year old thread.  I think it would be better to start a NEW one and just refer to this thread.

 

In addition, I'd like to suggest that you post it in the section that corresponds to the board that you're using rather than in the Beta firmware section.

 

When you do that could you please post EXACTLY the model of the Netduino that you're using and the exact level of the firmware that you're running on, including whether or not you have the Netduino.IP assembly added in.

 

Further, I'd like to suggest that you place the card in your PC's card reader & do a reformat.  I did have one card that I had previously used with my GPS that was in a weird format after I took it out of the GPS.  After reformatting the card, the problems I had using it (with an Arduino, at the time) went away.

 

FYI - I have 3 Netduino Plus 2 boards and I have been successful in using FAT32 formatted SanDisk MicroSD cards in them.

 
Lastly, do you think you could boil your code down to a 10-line "snippet" and post it here also?  Happy to look at that for you.



#64390 How to interface and measure a capacitive sensor?

Posted by TechnoGuy on 28 October 2015 - 05:36 AM in General Discussion

This is intended as a quick reply / acknowledgement to offer some first impressions.

 

Basically I think what you have is "base level technology" there rather than "application level technology".  I would think that a company like Adafruit or SparkFun Electronics (but probably not for this particular technology) would be the ones to devote engineering resources to take the base level technology up to application level through the design & implementation of some sort of interface module (which would incorporate the circuit designs presented in the data sheets in one way or another).

 

Anyway, at the typical application level - for interfacing with sensors - that would usually be done with an analog type arrangement - i.e. reading a voltage level & scaling it (doing math) to convert it to the intended units or with a digital arrangement (I2C, OneWire or SPI - where there's a bit of intelligence in the module).

 

My thoughts are just this - if you're new to interfacing with sensors and just want to learn about physical computing - you probably picked the wrong type of sensor to start with.  However, it does seem like you've overcome initial hurdles & are on your way to a workable solution.  So that being said - I think it's a sign that you are on top of things.

 

More comments in a day or two (after I've read the application notes).  I was assuming you had a simpler type of device; I may not have much to add...




#64387 How to interface and measure a capacitive sensor?

Posted by TechnoGuy on 28 October 2015 - 03:07 AM in General Discussion

Could you please post details about your sensor please?  Things like Manufacturer & Part # would help.  If you could post a photo of your sensor that would help also.

 

Chances are that you have 3 pins on your device, though and they are:

 

  • 3.3 V (or maybe 5 V):  Supply Voltage
  • GND:  Ground
  • SIGNAL:  A variable voltage ranging from 0.0 V to the supply voltage level

 

If you could just confirm the details of what you have, I think it should be possible to advise you properly.




#64311 Netduino Plus 2 Firmware v4.2.2 (update 2)

Posted by TechnoGuy on 15 October 2015 - 07:57 PM in Netduino Plus 2 (and Netduino Plus 1)

Hi,

 

I've noticed an interesting issue with the latest version of the firmware. I upgraded my Netduino Plus 2 to run 4.3.2.2 and the following fails on this version of the firmware.

 

public DateTime GetNetworkTime(string hostName = "time-a.nist.gov")

{

            var hostEntry = Dns.GetHostEntry(hostName);

.....

}

 

Rolling back to 4.3.2.1 of the firmware and the same code executes fine with no changes.

 

I'm pretty sure there is a firmware issue as I received my Netduino 3 (Ethernet) board today and deployed my application to the new board (it is running 4.3.2.2 out of the box). It fails on the same line of code.

 

An unhandled exception of type 'System.Exception' occurred in Netduino.IP.LinkLayers.AX88796C

 

Any suggestions?

 

Thanks.

 

Hi,

 

You've posted comments about version 4.3.2.x of the Netduino Plus 2 firmware in a 2-year old thread which is concerned with an earlier version of the firmware (4.2.2.x).

 

I think it would be better for you to start a new thread.

 

What I will tell you here is that, although there is a downloadable file called Netduino Firmware 4.3.2.3 (September 2015) currently posted as being available, it actually contains multiple individual firmware updates that are targeted at 6 different Netduino variants.  The firmware version for the Netduino Plus 2 is only at 4.3.2.1 within that file.

 

If you'd care to start a new thread I'd be happy to continue the discussion with you there about what I think the problem is.




#64305 TimeService.SetTimeZoneOffset now throwing NotSupportedException

Posted by TechnoGuy on 14 October 2015 - 11:54 PM in Netduino 3

Paolo Patierno has some interesting comments on this as well.  Please see his January 2015 article:

TimeService and .Net Micro Framework : the importance of date/time in the IoT

http://www.embedded1...time-in-the-iot

 

Chris - I am hoping you could please take a look at this problem & let us know what's up.  Thank you.





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