lesmondo's Content

#23157 Neduino & IN13 Nixie Bargraph

Posted by lesmondo on 23 January 2012 - 03:29 AM in Project Showcase

Hey

First off I should say:

Warning!!! This circuit uses high voltage that may well kill you if you don't understand what you are doing!!!!

Also, if you mess up the wiring and put 120+ volts into your netduino, it wont't be very happy.

The display is part of a larger project hence the schematic appearance. R4 goes to a PWM output pin, the Anode to the HV PSU output pin and gnd to the HV PSU gnd and netduino gnd. Just to re-iterate the warning above, if the schematic as-is doesn't make sense or you are not sure of the schematic or what voltage is where, you shouldn't attempt this.

Something I did miss was the transistor type. Any HV one will do - an MPSA42 or MJE340 seem a popular choice.

In the video, the HV supply module is in the top right connected to its 12V supply via the red and black twisted leads. The HV output is the yellow wire to the anode of the tube. Gnds are tied together and are the black leads.

The tube as supplied has uninsulated leads, mine are covered in some heat shrink sleeving.

If you want to know more about these cool tubes, google IN13 bargraph will turn up lots of links. I'll also add the datasheets to my blog a little later today.

How it works

The RC filter acts to 'smooth' the PWM output into a control voltage.

R5 controls the current through the tube which in turn controls the length of light displayed. 1K is a starting value, if you find that netduino output doesn't drive the tube fully, you can reduce it. Assuming the base of the transistor is at 3.3V (the output voltage of the netduino at 100% duty cycle) the indicator cathode current will be

I = (3.3 - Vbe) / R5.

for an IN13 (from memory) this should be 3-4mA to light fully. Taking Vbe = 0.7, R5= 1K will give you 2.6mA. You might want to drop this in steps to say 470R if you find your tubes are lighting fully (they vary a lot).

R6 is for the auxiliary cathode - this helps to stop the display from breaking into multiple blocks (something the IN9s do apparently).

Hope this answers the questions. And be safe

Les

#23096 Neduino & IN13 Nixie Bargraph

Posted by lesmondo on 21 January 2012 - 11:19 AM in Project Showcase

Hey, Just updating the blog wth a few bits and pieces. Nothing special, just PWM driving an IN13 nixie bargraph display. http://nerduino.word...nixie-bargraph/ Les

#22645 Response: Pinging... Error: No response from device

Posted by lesmondo on 10 January 2012 - 06:50 AM in Beta Firmware and Drivers

If you have not done so already, could you take a moment and upvote the issue at these sites?

Device becomes inaccessible after deploying 4.2.0RC3 Firmware

Flashing tinyclr 4.2RTM to Netduino fails

Thanks

Done.

#22509 Response: Pinging... Error: No response from device

Posted by lesmondo on 06 January 2012 - 07:09 AM in Beta Firmware and Drivers

Hi Just to let you know, I've reverted back to RC1 since RC3 was giving me the No response error on XP - same issues as above. L

#22427 Netduino SDK API

Posted by lesmondo on 04 January 2012 - 05:30 AM in Netduino Plus 2 (and Netduino Plus 1)

And here's how to add the SDK help docs to VS2010 for F1 context help. There's also some basic examples on my blog that you might find useful (a button, an led etc.) http://nerduino.word...mf-vs2010-help/

#21973 Button OnInterrupt Reset

Posted by lesmondo on 22 December 2011 - 07:44 AM in General Discussion

As i was using the on board switch i got it working by doing the following:

public static InterruptPort button1;
public static void Main()
{
	button1 = new InterruptPort(Pins.ONBOARD_SW1, true, Port.ResistorMode.PullUp, Port.InterruptMode.InterruptEdgeLevelLow);
			
	WaitForButtonPress();
}

private static void WaitForButtonPress()
{
	Debug.Print("Waiting for button press...");
	button1.ClearInterrupt();
	button1.OnInterrupt += new NativeEventHandler(button1_OnInterrupt);
	while (true)
	{
		Thread.Sleep(15);
	}
}		
private static void button1_OnInterrupt(uint data1, uint data2, DateTime time)
{
	Debug.Print("Onboard button pressed");
        WaitForButtonPress();
}

This might be of interest - a general purpose button class. http://nerduino.word...1/02/24/button/ (derived from http://geekswithblog.../09/142211.aspx )

#21207 Integrated Help files and documents?

Posted by lesmondo on 01 December 2011 - 07:13 AM in Visual Studio

http://nerduino.word...mf-vs2010-help/

#21206 VS2010 Pro Free

Posted by lesmondo on 01 December 2011 - 07:09 AM in Visual Studio

No, it's not a shady pyramid selling scheme - it's a trapezoid model!

MS are giving away VS2010 Pro, Blend, SQL server and Win 2008R2 to "professional developers" via the websitespark program. http://www.microsoft...b/websitespark/ Of course, you're all professionals aren't you (ahem, cough cough). Students can get even more through dreamspark. https://www.dreamspark.com/ Happy Christmas.

#21204 Netduino Plus... disenchantment is the word

Posted by lesmondo on 01 December 2011 - 06:59 AM in Netduino Plus 2 (and Netduino Plus 1)

Hey Doug, I'm building a project that'll sit on our corporate network and can relate to your problems. Basically, networking was (and still is) toast unless the NPlus is plugged into a separate unmanaged switch. Wireshark in our test lab showed the problem to be related to some cisco discovery packets causing the board to reset. I ended up getting a small 4 port TP-Link switch from ebay. Since moving to my cheapo switch, it works fine. Except for DHCP - that has never worked for me on various networks. Hope this helps. Les

#20097 Help with PWM and LEDs

Posted by lesmondo on 02 November 2011 - 12:18 PM in Netduino Plus 2 (and Netduino Plus 1)

I'm currently playing with the PCA9622 - I2C 16 o/p 40V PWM LED driver. http://www.nxp.com/p...ol/PCA9622.html I'm still at the early prototype stage, so no code or hardware to post yet (the board is still at the fab house). Just thought you might be interested. Les

#18401 Easy multiplexing with the Netduino

Posted by lesmondo on 25 September 2011 - 12:58 PM in Project Showcase

Sounds like a great plan! Mario's advise is a good one. If you can make the shield 'daisychainable' it would be awesome!

Hey, Thanks for the input. I wasn't planning on making these or selling them, it's just a project for me to update my PCB making skills. But once I've got the board working and debugged I'll post the cad files and a write up on my blog.

Of course, if you want the files now, just shout and I'll chuck them and some code into github.

L

#18400 Need Documentation for Netduino(SDK)

Posted by lesmondo on 25 September 2011 - 12:54 PM in General Discussion

thanks for helping .....

The microframework doco is installed with the SDK. If you want to add it to the F1 context help in VS2010 try this.

http://forums.netdui...dpost__p__18065

#18344 Easy multiplexing with the Netduino

Posted by lesmondo on 23 September 2011 - 02:56 AM in Project Showcase

Hey Shifting Gurus

It's been a while since I last made a PCB (think dinosaurs) so I was looking for a little project to learn how to make use of the cheap fab available to hobbyists and the obligatory reflow toaster oven. Inspired by this thread, I knocked up this little 595/165 port expander. I've been staring at it for days now and I'm sure it's OK to send off for fab but I just wanted to ask you guys to sanity check it. BTW LEDs are Vf=3.3 If=20ma pink ones (my daughter loves pink). Thanks Les

Attached Thumbnails

#18272 Cortex M3 Arduino

Posted by lesmondo on 21 September 2011 - 05:38 AM in General Discussion

http://www.edn.com/a...3_processor.php

There are a myriad of differences. I'm a big fan of the Cortex, and I've been bugging Walker to head that way for a while.

Thanks, that's exactly the kind of article I was after.

#18115 Cortex M3 Arduino

Posted by lesmondo on 17 September 2011 - 02:06 PM in General Discussion

Hey Was just reading this from a few years back http://www.arduino.c...um=1227128468/0 Seemed like a more powerful processor with a less powerful set of tools than netduino. Got me wondering why netduino is ARM7 based? Can someone explain the diff between the M3 and the older ARM7? Edit: This seems more recent. http://www.electroni...o-community.htm Ta Les

#18065 where is the .net micro framework documentation?

Posted by lesmondo on 16 September 2011 - 04:04 AM in General Discussion

Sorry to dig up an old thread, but I wondering the same thing. Anyway, I've just written this up on how to add the mf help files to visual studio's help manager. Feedback welcomed of course. http://nerduino.word...mf-vs2010-help/

#18061 Network Resetting Issue

Posted by lesmondo on 16 September 2011 - 02:14 AM in Netduino Plus 2 (and Netduino Plus 1)

Les, are you able to anonymise the capture data (without jeopardising it) so that a bug report can be submitted on CodePlex including the capture?

Update: I bought a cheap 10/100 switch from ebay and that's fixed the problem

#17797 Nplus to 74141

Posted by lesmondo on 09 September 2011 - 06:41 AM in General Discussion

Hi, No, it's not for another nixie clock... but I was wondering about connecting an N+ to a 74141 nixie driver. The datasheet says Vih > 2V Vil < 0V so I'm guessing that the 3.3V I/O pins will work fine? Ta Les

#17302 Network Resetting Issue

Posted by lesmondo on 31 August 2011 - 02:33 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi All, I've managed to get one of our networking gurus to do some wiresharking and it appears that it's the Cisco Discovery Protocol packet(s) that are causing the N+ network to reset. The N+ negotiates at 100mb full dup, the switch sends CDP, then N+ network resets. This repeats. I have the capture but since this contains site specific info, it's probably best if I don't attach them here. Does this sound like a MF problem or a N+ hardware problem? Thanks Les

#17044 Network Resetting Issue

Posted by lesmondo on 25 August 2011 - 05:55 AM in Netduino Plus 2 (and Netduino Plus 1)

Although your corporation might frown on it (some will)...
At my day job (an extremely large, security conscious corporation) we run on a gigabit switch network, some of us developers who need to use Wire Shark occasionally will also have a dumb, gigabit hub in our office… plugging in network, Netduino and your PC should allow you to “see” what’s going on between your N+ and the (anti-social ) company switch.

Shhh..... they might hear you

That's what I'm hunting around for now. I'm also thinking that if it is the cisco switch/N+ combo that's the problem, maybe putting a cheap hub between the two might fix it.

#16964 Network Resetting Issue

Posted by lesmondo on 23 August 2011 - 01:16 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi lesmondo,

If other devices work on this router, I'm guessing that it's a glitch in the lwIP open source networking stack.

Could you please post a bug report ("work item/issue") on this over at netmf.codeplex.com? The .NET MF 4.2 release is almost ready to ship...so this is the last chance to get critical bug reports in. [Otherwise, it could be a year before the issue is addressed in an official release.]

Also...do you have a copy of Wireshark? It would be really helpful to see a copy of the network traffic...see what is arriving at the Netduino Plus and what is going out...

Chris

Hi Chris,

I'll raise a bug report. Unfortunately since our network is switched I don't think I'll be able to capture the N+ packets - my PC doesn't see them.

Les

#16832 Network Resetting Issue

Posted by lesmondo on 19 August 2011 - 01:22 AM in Netduino Plus 2 (and Netduino Plus 1)

Hi oofki,

The Thread.Sleep function simply puts the main thread to sleep...you can have background threads running (including networking) without any issue.

Chris

Thanks Chris, like I said this was my simple as possible test case. Any ideas as to why the network would be resetting like this?

#16810 Network Resetting Issue

Posted by lesmondo on 18 August 2011 - 05:02 AM in Netduino Plus 2 (and Netduino Plus 1)

Can you post the code you are using?

Sure. It's basically:

main() { while(true) { Thread.sleep(5000); } }

I thought it was something to do with my code so simplified and simplified until I ended up with that. If you erase the app using mfdeploy so that there's no running program it still does the reset thing.

After reading this, http://forums.netdui...in-the-network/ it looks like I'm seeing the same issue - the link going up and down repeatedly.

#16790 Network Resetting Issue

Posted by lesmondo on 17 August 2011 - 12:18 PM in Netduino Plus 2 (and Netduino Plus 1)

Hi, I've been playing with N+ at home plugged into my ADSL router/modem (Billion 7800G) and it works just fine. However, today I took the board into work and had a strange issue when connected to our network. Plugging the N+ into our network - which I believe is some flavour of a cisco gigabit switch - causes the network adapter on the N+ to appear to continually reset. By this I mean the three n/w leds turn on, one blinks a few times then all three turn off for a couple of seconds. This repeats. Originally I was using HttpWebRequest to retrieve some data from a webserver on my PC. This code wass hanging on the GetResponse call. After simplifying the code, I've ended up with a main that only calls Thread.sleep in a loop. The network still appears to reset endlessly. I'm using a static IP and firmware 4.2. Curiously, about 1 in 100 resets, the board functions fine and I can ping it and make socket connections back to the server running on my PC. But for the other 99 times, the board is not pingable. I've brought the board home again tonight, changed the static IP to one on my network and the board works fine. So I'm wondering is it something to do with the networking hardware at work? Thanks