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#59281 Windows on Devices? When?

Posted by sfx on 17 July 2014 - 01:09 PM in General Discussion

 

Does anyone understand why a device would boot windows then provide an exact emulation of an arduino (using wiring as the language and NO ui?).

 

Provide an emulation for a heretofore foreign experience on Windows? Yes. Microsoft has done this before (much to the chagrin of some of its developer community). Recall that Microsoft unleashed JavaScript - a foreign language - into WinRT development with the sole ambition of luring a broader cross-section of developers into their fold. Microsoft must think there is enormous money in the IoT, and it appears they want to cast their net as wide as possible.

 

Shake an apple tree and you better have a bucket ready. Shake an orchard, and...

 

Nathan



#59227 Windows on Devices? When?

Posted by sfx on 15 July 2014 - 05:30 AM in General Discussion

Hi Dr Who,

 

Yes, that's true. Unfortunately, I also noticed (or at least couldn't find) references to either the Netduino or NETMF on the IoT Developer portal...

 

Nathan



#59211 Windows on Devices? When?

Posted by sfx on 14 July 2014 - 05:38 AM in General Discussion

Hi All,

 

Looks like there has been an update:

 

http://blogs.windows...am-for-iot.aspx

 

Nathan



#59012 Simple Sensor Interface - SSI protocol?

Posted by sfx on 04 July 2014 - 11:37 PM in General Discussion

Hi Frode,

 

Having a standard communication protocol is a great idea. However, without manufacturer compliance implementing this type of protocol (SSI) would require quite a bit of work in order to cover all of the command types (not to mention having to potentially map a host of pre-existing proprietary commands).

 

One idea might be to hide all of the commands behind an SSI interface or break the commands up into multiple SSI interfaces (e.g. ISsiConfiguration, ISsiReader, ISsiStream). That way you aren’t forced to implement functionality that is ill-suited to your sensor, and you also provide all callers with an immediate understanding of what aspects of the SSI protocol have been implemented.

 

Nathan



#58361 Sensor Cable Length

Posted by sfx on 23 May 2014 - 07:13 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Guys,

 

I haven't been able to find out how long the recommended practical limit for a sensor cable is, but I did find that Pololu offer pre-crimped terminal cables up to 5ft in length.

 

Take care,

 

Nathan



#58322 Sensor Cable Length

Posted by sfx on 21 May 2014 - 12:56 PM in Netduino Plus 2 (and Netduino Plus 1)

Hi Folks,

 

How long can the cables/wiring be when connecting a sensor (say 3/4 pin) to the Netduino Plus 2's digital or analog ports?

 

The reason I ask is that most suppliers seem to offer cables up to around 30cm, but I was hoping to be able to purchase something 2 meters or longer in length.

 

Best regards,

 

Nathan



#58981 Sending break over serial port

Posted by sfx on 03 July 2014 - 02:57 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Chris,

 

Just found this post and was wondering if you had any updates concerning it? This is an important requirement for me too. I'm having a similar issue with serial port BreakState and would also like to see a framework solution to this problem.

 

See my recent post here:

http://forums.netdui...and-breakstate/

 

Nathan



#60330 SD Card Write issue

Posted by sfx on 03 October 2014 - 12:08 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Dizel,

 

The full .NET Framework will ensure that a FileStream object is disposed of by any wrapper objects that get created (e.g. StreamWriter etc). Because of this, it isn't necessary to call dispose (via a using statement) on a wrapped FileStream since the wrapper will do it for you. Of course, in the interests of readability and consistency it is good practice to always explicitly declare your intentions on a FileStream with either a using statement or a try/finally block. However, I'm not sure if NETMF behaves the same way as its big brother on this.

 

At any rate, it appears that instead of your StreamWriter instance wrapping your FileStream object both are wrapping the shared file path. This indicates to me you have two Stream derived objects competing for the same resource at the same time.

 

Try this:

using (FileStream file = new FileStream(fileWrite, FileMode.OpenOrCreate, FileAccess.ReadWrite))
using (StreamWriter wr = new StreamWriter(file))
{
    wr.WriteLine("Hello");
    wr.WriteLine("StreamWriter");
}

Take care,

 

Nathan



#58748 obstacle detection

Posted by sfx on 17 June 2014 - 05:28 AM in General Discussion

John,

 

This is a great idea! I've thought about how to do this myself, but your idea of using headers sounds like the cheapest and simplest approach I've heard. Nice work!

 

However, can I ask what you mean by "shrink wrap"? Are you referring to electrical tape, or something else?

 

Nathan



#59274 New Robot Meetup Group, Seattle

Posted by sfx on 17 July 2014 - 04:29 AM in General Discussion

Hi Spiked,

 

Good to hear! Keep us all posted on any further developments regarding meeting access. I, for one, would really appreciate the benefit that this type of experience would bring.

 

Nathan



#59269 New Robot Meetup Group, Seattle

Posted by sfx on 16 July 2014 - 11:31 PM in General Discussion

Spiked,

 

What a fantastic idea! I would love to be able to attend this kind of setup, but unfortunately I live far, far away (and there aren't any facilities like this around where I live).

 

Would it be possible to video record the meetings and then make them available offline? Obviously there would be costs involved in this, but I'd be happy to pay for any expenses. If downloadable material is too cumbersome to setup, how about a no-frills mail order DVD?

 

Nathan



#59327 New Robot Meetup Group, Seattle

Posted by sfx on 21 July 2014 - 09:52 AM in General Discussion

Hi Spiked,

 

So I guess that means I won't be getting any video recordings of your affronts (ahem... efforts)?

 

Sorry to hear that it did not go down so well. It sounded like many weren't there to grow, but to agro instead. I guess it doesn't come as a huge surprise, really, since I've seen my fair share of egoism and self-aggrandisement within the software community as well. Sadly, many of this type adroitly tout their cross-discipline expertise while at the same time being blissfully unaware that their behaviour satisfies the Dunning-Kruger effect.

 

Please don’t give up, though. Many here can still learn from your expertise and there are undoubtedly a plethora of matters where your contribution will be both substantive and welcome.

 

Nathan



#59189 NETMF SerialPort and "BreakState"

Posted by sfx on 13 July 2014 - 10:11 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,

 

Sweet indeed.

 

As usual, thanks for the great references. Thanks also for your code samples. I’ve put them in a folder called “Baxter Serial”. Now there’s a name for a new design!

 

I’m going to purchase the HR-SR04, but I’m ideally on the lookout for a single transducer range finder so I’ll probably purchase something from MaxBotix as well (though I’m not sure about the connections on these since I’ll probably have to solder [something new again] wires to them).

 

Of course, I’m open to any further suggestions you have. Hopefully I’ll be able to build something out with these that doesn’t cost me my sanity.

 

Nathan



#59036 NETMF SerialPort and "BreakState"

Posted by sfx on 06 July 2014 - 07:12 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,

 

Thanks for the reference. Actually, I saw this a few days ago but I didn't understand it until you explained the configuration in a couple of your previous posts.

 

I'm still waiting on my header wires to arrive, but hopefully I'll get to test the setup within the next few days.

 

Nathan



#59071 NETMF SerialPort and "BreakState"

Posted by sfx on 07 July 2014 - 11:26 AM in Netduino Plus 2 (and Netduino Plus 1)

Ok, here goes nothing...

 

My header wires arrived today so I was able to set up my Netduino Plus 2, range-finder (SRF01), and logical AND Gate exactly as my last diagram describes (with the help of Baxter). After nearly two hours of frustration the results are in:

 

1. Range-finder flashes on power up.
2. Debugging session begins ok.
3. Break command is sent to the sensor.
4. Two commands follow (the sensor address and the status command).
5. All bytes appear to be written.
6. No bytes are available to be read back (that's right, zero bytes).

 

According to the documentation, I should be receiving bytes back as representing a return value from the previously sent command. I get nothing. It's as if the break command isn't being sent at all and so the sensor isn't even aware that anything has happened.

 

I'm lost.

 

Nathan



#59113 NETMF SerialPort and "BreakState"

Posted by sfx on 09 July 2014 - 01:18 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,

 

It goes without saying, but I really appreciate your patience with me on this.

 

As per your suggestion, I’ve ordered a USB adapter similar to the one here:

http://www.ftdichip....0_R-100-500.pdf

 

Just so you know, I have multiple SRF01’s available to use and have tested with more than just one. Unless I received a bad batch, then they all seem to be working the same way (power flash appropriate to the tech specifications). Additionally, the code that you referenced is the code that I have actually been working with since the beginning – I’ve only been consulting the Arduino code as a secondary verification.

 

I’ve attached another image showing what I think you were saying about connecting a serial port to a diode. Please let me know if I’ve misunderstood you. Once I have the serial adapter, I’ll test out this configuration along with any further suggestions you have.

 

Nathan

Attached Thumbnails

  • Serial-Diode_v1.jpg


#59140 NETMF SerialPort and "BreakState"

Posted by sfx on 10 July 2014 - 09:55 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,
 
While I'm waiting on the USB to TTL adapter to arrive, I thought I would try to implement the transistor based half-duplex UART configuration that you mentioned to me earlier:
 
 
I have attached a diagram for the circuit in the above web page, but my circuit reading ability is still in its infancy and so I have a strong hunch that I have got it wrong. When you get a moment, I was hoping you could point out the innacuracies that I have made.
 
As I have each of these parts I'm hoping to be able to test out this configuration using an SRF01 as well.
 
Nathan

Attached Thumbnails

  • Half-Duplex-Software-UART.jpg


#59210 NETMF SerialPort and "BreakState"

Posted by sfx on 14 July 2014 - 05:34 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi jrlyman3,

 

Thanks for the feedback. I'm definitely going to test out a HC-SR04 now.

 

Nathan



#59100 NETMF SerialPort and "BreakState"

Posted by sfx on 08 July 2014 - 01:19 PM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,
 
This stuff is going to haunt me, I know it... But thanks again for your help.
 
I managed to pick up a 2N3904 NPN transistor as well as a BAT 48 Shottky diode (they didn't have an 85 so it's on order).
 
I'll start with the diode attempt as per your suggestion from the spec page for the Atmega32. I have attached an image with the setup that I have created, but I'm not sure if it is accurate. I was hoping that you might be able to offer me some suggestions here.
 
At any rate, I know that this configuration will not allow me to reference serial COM1 on the Netduino if I'm also attempting to use either pin D0 or D1 to furnish the "break" command - an InvalidOperationException will be thrown due to a conflict on the pins. Consequently, I'm not sure how using just the diode solution will work with the Netduino. I think I understand how it would work on the Arduino or Atmega32 given that RX and TX can be referenced on the same pin, but such doesn't appear to be the case on the Netduino.
 
And so I'm back to where I started... Confused, bemused and abused.
 
Nathan

Attached Thumbnails

  • post-151462-0-35758800-1404.jpg


#59019 NETMF SerialPort and "BreakState"

Posted by sfx on 05 July 2014 - 08:15 AM in Netduino Plus 2 (and Netduino Plus 1)

Baxter,

 

Thanks for examining my diagram. I appreciate it.

 

I've swapped the 1A and 1B wires and moved the RX wire from the sensor to 1Y  on the IC instead. Attached is an image based off your recommendations.

 

If you notice anything else amiss, please let me know.

 

Once my header wires have arrived, I'll construct the prototype and see if I can finally catch a break (pun intended)!

 

Nathan



#59087 NETMF SerialPort and "BreakState"

Posted by sfx on 07 July 2014 - 10:08 PM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,

 

I haven't picked an easy part to start my hardware adventures, you say? Well, you can say that again!!

 

I noticed the diagram that you attached a week or so ago but for some reason thought that it only applied to serial connections to a PC. I also noticed that some of the code I was attemping to translate from Arduino was referencing the RX/TX line together - as if it was one physical wire that could be engaged as either Receive or Transmit based upon a flag. This is obviously not the way Netduino works.

 

The Arduino code is linked to here: http://www.robot-ele...duino_srf01.ino
 

Looks like I need to get a BAT85 schottky diode. However, there are still a couple of questions that I'm not sure about:

 

a ) Does one leg of the diode need to connect to D0 and the other to D1 (i.e. RX/TX)?
b ) How does the RX line of the sensor connect to the diode if both legs are already plugged in?

 

I'm learning a lot while making all these mistakes, so I've appreciated your help immensely. If I can get this sucker working finally, I'm going to shout you a round of beer!

 

Nathan



#59156 NETMF SerialPort and "BreakState"

Posted by sfx on 11 July 2014 - 12:02 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,

 

Wow! Thanks so much for taking the time to diagram that circuit out for me. I really appreciate it.

 

Thanks also for the reference to EasyEDA. I haven’t heard of it before (not surprisingly), but will start playing with it immediately.

 

I’ve created your diagram on my Netduino Plus 2 and attached a picture of the result. I think I have everything in essentially the same order as you.

 

Unfortunately, I’m still not reading anything on the SerialPort.BytesToRead property. It is always zero. This has got me thinking that surely it shouldn’t be as difficult as it has been to set this kind of configuration up on the Netduino. After all, the Arduino can read these sensors without even having to move a circuit out onto a breadboard! As such, I’m left wondering whether there is something wrong with my own hardware or if the NETMF doesn’t play nice with serial communication outside of its standard operational boundaries. I find both of these possibilities quite troubling, but also think that it’s most likely the former rather than the latter.

 

I guess I’m going to have to wait until the USB to TTL adapter arrives in order to see whether my Netduino can operate against the vendor’s PC code.

 

I’m reluctant to have to abandon my venture and admit defeat, but I’m also aware that I might well be out of my depth here. Still, I’m very thankful for all the guidance you have provided over these last few days – I have definitely learned a lot. Nevertheless, I realise that I’m likely stealing your time away from other important matters. Hence, in the event that I can’t get anything working I was wondering if you happen to know of any companies that could prototype the setup that I’m after on the Netduino board? If there are facilities that can offer this kind of service I’d be happy to pay to at least get me a working sample from which I can then build upon.

 

Thanks again.

 

Nathan

Attached Thumbnails

  • NP2_Half-Duplex.jpg


#59176 NETMF SerialPort and "BreakState"

Posted by sfx on 12 July 2014 - 02:06 PM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,

 

Sorry for the delay in getting back to you, I’ve been at this thing hammer and tong since we last spoke and wanted to be sure of my findings before I replied to your last post.

 

Thanks for the excellent references too. I’ve had the electronics book you mentioned for a little while now but haven’t acquired the starter kit yet in order to really get the most out of it. I’ve also read the books by Cuno and Chris and have been watching the videos on allaboutcircuits for a couple of weeks now. It’s quite a crash course!

 

Now for finally some good news… Since the last time I discussed this issue with you I went back to my setup (using your diagram) and realised that I had a 1N4001 diode in the place of where the BAT 48 Schottky diode that I had purchased should be. Well, guess what happened when I replaced the diode? It worked! I finally started to receive data back across the wire!! I therefore want to offer you my sincerest thanks as well as hearty congratulations. If it wasn’t for your help, I would never have got this far with my limited hardware experience...

 

Now for some not so good news… The code samples that I’ve worked on that were taken from the vendor’s website, as well as others that I’ve attempted to port from different platforms, don’t seem to work on the Netduino. The problem appears to be in how data is waited upon as well as how echo transmissions get discarded before any relevant bytes can be parsed – I just couldn’t get the Netduino to read anything but junk using the code samples I found online... And so...

 

Now for some interesting news... I did finally manage to get the range bytes by using the DataReceived event of the serial port, but only after what I consider to be a bit of a hack; or more specifically, by collaborating with the number of times the received event gets raised and then parsing the relevant bytes accordingly. It seems to work, but it’s definitely a code smell.

 

Due to all of these issues, I’m not certain I will settle on the SRF01 as the range finder I want to use on the Netduino. Nevertheless, it’s only because of your assistance that I’m even able to consider this option.  More importantly, your solution has not only helped me, but it will aid anyone who is searching online for how they can connect a SRF01 to the current release Netduino hardware.

 

Well done!

 

Nathan



#59114 NETMF SerialPort and "BreakState"

Posted by sfx on 09 July 2014 - 02:22 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,

 

Further to your last response (and in addition to mine), I'm still uncertain as to how to layout a breadboard diagram for the "half duplex" solution that you mentioned - I guess I'm not clear on how both the RX and TX pins from the Netduino will connect to the logical AND gate. I've attached an image as to what I think you mean, but was hoping that you could validate it against the intent of your previous suggestion.

 

I’m wanting to try this out even before your serial adapter advice as I already have the necessary items and will likely have to wait a few days before I can acquire an adapter.

 

Thanks again.

 

Nathan

Attached Thumbnails

  • Half-Duplex-v1.jpg


#59118 NETMF SerialPort and "BreakState"

Posted by sfx on 09 July 2014 - 09:45 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi Baxter,

 

No worries. I've cancelled the order and made another one for item (3) on your list. Hopefully I'll take delivery of it within the next few days.

 

Thanks also for the heads up regarding RS232 and TTL. Your explanation makes a lot of sense.

 

Regarding my Fritzing diagram, I have removed the blue wire as per your instructions but can confirm that this setup does not work using the GPIO with logical AND "break" substitute. More specifically, various commands can be sent without throwing an exception but the SerialPort.BytesToRead property is always zero.

 

Concerning the next to last diagram that I posted, I'll endeavour to build that out once my USB to TTL adapter arrives.

 

In the meantime, however, if you have any further suggestions or recommendations please let me know.

 

Nathan




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