Seems odd, i have an application which makes extensive use of the on board sd card, ethernet and spi port.

As Chris suggested are you using the secretlabs name space classes for SPI pin assignments etc.?

Nak.

@NooM

I forget the specifics but there is some licensing issues with sd cards which means that FOSS implementations have to license SDIO/the fast way of accessing cards. 

see this post for more details: http://tech.groups.y...00/message/2534

Which i believe to be one of the issues the ND+ (not sure about the ND+2 as i dont have one) had with being fairly picky with which cards it worked with.

Nak.

If i understand correctly then you are basically talking about the secret labs SDK.  The SecretLabs namespace contaisn things like enums for pin mapping and routines to access the SD card etc.

You can download the source for the SDK from the downloads page.

Nak.

You could override the to string method on the object to serialize it for you,  if you can use a less verbose syntax like json as it is much easier to manage the memory of the ND then, as strings are immutable and can consume large amounts of heap space.

Nak.

Nice work

May well have a use for this very soon as the day job has a very big investment in azure...

Nak.

Nice project, but as Paul said get that relay (and mains voltage wiring!!) safely stowed away in a box, preferably a waterproof one, can never be too careful.

Nak.

@JoopC

Its to do with patents on higher capacity cards, you have to license tech to use SDHC cards AFAIK and you cant access directly via SPI as they are currently on the ND.

Nak.

Try searching the forums

http://forums.netdui...ping#entry47297

http://unix.stackexc...m-a-bad-sd-card might be a useful starting point

But to be honest the time and effort to fix a 2gb sd card which will probably die again would be better spent on just buying a new one, you could even get one for free, as many companies give them away for promotions, i.e. i have a stack of cards from fluke who were giving them away pre loaded with marketing material for there thermal imaging kit.

Nak.

Sounds like as Noom said a dead SD card.

If its still within warranty return it and get it replaced otherwise get a new one, it seems highly unlikely that the ND is the culprit more likely you just have a duff card or its worn out.

In my experience when i have ordered SD cards in bulk i expect 1 in 20 to be faulty or to fail the soak test, so its entirely possibly you just got one from a bad yield.

Nak.

Cool look forward to listening, not sure why it hasnt showed up in my podcast feed... :-/

I assume that you implemented the reset circuitry on your custom board?

as AFAIK you need a method of grounding the MCU in order for it to reset.

Nak.

Putting it on a board is the logical next step.

I would start by trying the free PCB design packages (KiCad, designSpark or eagle) and seeing which you like most.

Follow some tutorials for each, then try and draw your schematic in your chosen package.

When your ready to get a board made, you can get them made quite cheaply at places like seeedstudios or oshpark.

Nak.

As enough said Generics are not supported by the microframework. 

That said you can create object arrays  and similar and 90% of what you could do in .net 1.0 you can do in netmf, so lack of genrics shouldnt be to much of a problem.  Generally if you need some of the higher level features of .net for your project to work you are working at to high level for netmf, try getting closer to the metal and looking at how those features are really used in your application.  It may mean a lot more casts than you are used to in standard .net but it is doable.

Nak.

Ahh yes the Netduino Plus 2 does i believe come with 4.2 already installed.

Check your netduino SDK is the lastest version, as its looking for 4.1 binaries.

Nak.

Have you upgraded your Netduino to the 4.2 firmware as well?

And installed the Secret Lab 4.2 SDK and updated your references in the project?

Can see a load of references to 4.1 assemblies.

Nak.

Pete Brown (yes Pete Brown the active forum member here ) is on Scott Hanselman's pod cast hanselminutes this week:

http://www.hanselmin...with-windows-81

Wonder if this forum has the most active members to have appeared on hanselminutes in the world, well can think of 2 people off the top of my head who have been on so that must be some sort of record ...

Nak.

AFAIK the hardware watchdog is already used under the hood by the micro framework (i might be wrong though), however i dont think a typical hardware watchdog will be much use to managed code as they tend to operate in mS timeframes whilst the netduino has (and netmf in general) has a bit of a non standard usecase as explained by Mario here: http://highfieldtale...r-the-netduino/

Nak.

I have always created shields to go onto top of netduino's for the simple reason that if either fails you can swap the part out, also you could conceivably port your netmf code to arduino, or any of the 'duino foot print dev boards out there.

That said if you want to design your own board then you will need to download the schematics from the downloads section, transcribe them into your CAD package of choice (i.e. design spark, or kicad the free copy of eagle doesn't support enough PCB layers or pads), remove the parts you don't want then route the board.  Something to be aware of is that AFAIK the ND boards are 4 layered boards which add a lot to the cost of board production and complexity of routing.  Also Secret Labs have spent a lot of time designing the boards to minimize EMR which may or may not prohibit you from selling your custom board depending where you live in the world (EMR testing and compliance certification can cost thousands).  So in short yes its possible to integrate all into a single board but its a frankly huge undertaking and would be much easier to design a shield instead instead of reinventing the wheel.

as for small production runs you could try http://oshpark.com/ or http://http://www.se...tml?cPath=70_71 for your board fabrication

as long as u use the same mcu and keep the pin allocation the same then firmware should run as is, and as for flashing your program you could use mfdeploy to deploy to each board once fabricated and assembled.  It looks like it would be possible to modify mfdeploy to support multiple (parallel) deployments to several devices at once, but AFAIK no one has made such a modification.

Update

I also forgot to mention that for small runs i.e. < 1000 you probably wont be able to source all the components for the ND and get the board fabricated for less than the cost of a ND.

Also factor in at least 2 prototype runs of your custom design as guaranteed your first one will have some issues (parts to close, incorrect routing), plus the debugging and verification needed to ensure that your ND clone is 100% compatible etc.

All in all if you total up the time spent not working on your application but spent on cloning the ND and getting it working as well as the $40 dollar board you would be looking at several hundred hours of work, on top of your project.

So lets say you could do everything in 350 hours, and assume you would charge $20 an hour if you were doing this work as a contractor you would be looking at a cost of $7000 to develop the device plus the cost of the components (approx $35 per board just for the ND components and pcb as i assume you wouldnt be buying in volume) , then to break even (no profit) the cheapest you could sell the device for is $73.50 assuming you have 100 made plus the cost of the components for your project.

Where as if you were to just build a shield then its just the cost of your components and board run and time spent getting your project up to production standards.

Annother factor to consider is getting the right tools, at the very least i would say you want a logic analyser (cheap ones start at the $50 mark), but a scope would be very useful possibly essential based on your project needs ($350-how much ), plus surface mount soldering gear, say a hakko fx series solder station ($100+), tips ($10 each), lead free solder, possibly a hot air rework station), so factor in $1000 to get production quality tools as well.

That said you can get away with whats to hand but if you are considering production you have to be able to achieve a pro level of quality and service and cheap kit wont help that.

Sorry if this seems very negative I just cant see any commercial sense in cloning the ND just to have a single board solution, that said designing a shield is much easier and cheaper.

Hopefully this hasn't put you off your idea and i look forward to seeing what you come up with

Nak.

Ahh cool, i actually designed a board which was integrated into vending machines where i powered the ND via the 5V pin (as long as your regulator is solid it shouldn't be a problem) i ended up using a LM2596T as a simple switchmode PSU integrated into the shield as the only voltage i could rely on was 24V AC!

Have you tried wrapping your socket in a using block, to ensure it gets disposed on error?

You could also add a finally block after your catch to manually call Dispose() on the socket

Also unplugging network cables isnt a very good test of network connectivity problems in my opinion as disconnecting the media is entirely different to intermittent connectivity to a server.  If you look at the OSI Model (http://en.wikipedia.org/wiki/OSI_model) you are trying to simulate a layer 5,6 or 7 issue by unplugging layer 1.  Generally the only time a network would fail like a unplugged cable is if someone unplugs the cable or if you have a power failure, in which case (unless you are running on batteries) your ND will probably be power cycled as well...

The way i have tested for things like that in the past is to have the server's firewall block requests, or have the software black hole random requests, so the socket is left hanging etc.

Nak.

Out of curiosity why do you want the usb power to be switchable?

I can understand the use for the barrel socket in case you are running on batteries, but usb would be powered from PC so would have a ready supply of power?

Nak.

Depends on how you want to use the device:

if you want the PSU integrated then you cant really go wrong with a LM7805 based circuit (as long as your current requirements are < 1.5 amps), you could also look at some of the simpler switchmode designs.

If the PSU is for bench use, then you cant really go wrong with an old PC power supply. there are loads of tutorials on the net about turning them into a bench PSU, then real advantage is that the current availible in even the cheapest of ATX PSU's is far in excess of most hobbyest needs and you have at least 3 very well regulated voltage sources (3.3, 5 and 12v)

Finally as the Dr. suggested a plugin "wall wart" style power supply can also be used.

Nak.

No Problem

Along with 74 series of logic gates the LM78xx and LM79xx (-ve voltage regulators) are some of the most often used hobbyist components, also worth noting is the venerable 555 timer chip, and the LM317&LM337(-ve version) adjustable regulator (0-15v).

You may want to get a small heatsink for the regulator as they do warm up during use, but as long as your current requirements are low then heat shouldn't be to much of a problem.

Nak.

Assuming the emulator lives in either program data or program files you probably will run into issues trying to debug or attaching the debugger due to the (relatively) new security features in win7+8.  If the emulator runs fine when you run VS as an admin then you could try moving the exe outside of programfiles and altering your project debug settings to launch from the location you copied it to, it may well work fine then without admin privileges...

The same thing can happen when trying to use IIS instead of IIS express when developing ASP.Net apps.

Nak.