This may be a wild and crazy idea, but why can't the waste heat from the LEDs be used in some way to heat the water in the aquarium? It just seems really wasteful to be cooling the LEDs at the same time as one is running a heater in the water. Some PCs are water cooled, is there any way to have a water cooled LED mount?

The BOCS arrived in Maine! The box arrived here in Phillips, Maine yesterday. Is anyone interested in having a box opening party? I know Phillips is rather remote, so I am open to traveling to Portland, Bangor or Augusta ME to meetup with anyone who would like to share in the fun. I am even open to traveling to Portsmouth, NH if that is better for people. Please respond if you are interested. I do not want to hold the BOCS up too long, so we need to do thus soon if you are interested. Today is Tuesday, 4-OCT-2011. If nobody responds by tomorrow night, I will simply open it by myself and then send it along on Thursday.

I just did a blog post at: http://www.bitsconne...-crappy-surplus describing my experience whit the BOCS, including photos.



As a teaser, this is an image of what I added to the box.

For those of you following, I had no takers for a box opening party, but hopefully we can organize some Netduino Days at hackerspaces and other locations in the future.

I am definitely interested and would like to participate :-) Would anyone else be interested in having "box opening parties"? My thought is that a bunch of us could get together at a house, hackerspace or restaurant and all open the box together. We would all bring stuff to swap as well and then put our extra stuff into the box before sending it on to it's next destination. Not only would this save on shipping, but would be lots more fun to share the excitement with others. It would be educational as well in that instead of simply taking something out of the box and wondering "what could this be", there is a good chance that someone else would recognize it and perhaps say "oh, that's a switch from the from panel of a DEC PDP 8 just like I used to work on in college". I am in Northwest Maine, and would welcome any Netduino fan to my house anytime if you want to come by and "play" Netduino. For the box however perhaps Portland, Maine or Portsmouth, NH would be a more convenient place for a Netduino fan club get-together?

The BOCS left Phillips, Maine (USA) today (Tuesday, 11-OCT-2011) on its way to David Stetz. The Post Office tells me it will take 2-3 days, so hopefully David will have it by Friday. I took photos and will post them here later today.

I would like to start by building two modules: 1) A slide potentiometer first to get my feet wet. Circuit should be the same as the existing potentiometer module with a slider instead of a rotary control. 2) A rotary encoder module. Of course I have plans for more, but one needs to crawl before one walks or runs ;-) And I should add that both of these will be open source hardware and software.

Would it help if we bought a few thousand of each and bundled them in 10-packs for $9.95?

Chris

P.S. All of the PNs are in the .BRD design files.

What would be even better would be a couple of sockets and pre flashed STM8S bundled together for $4.95

Where can one find the bill of materials for the existing Secret Labs go modules? In particular I would like to know the manufacturer, part number and sourcing information for the socket. Thanks.

As part of this conversation, we should put together a workflow of best practices for building modules.

Chris

Absolutely! That would be great. Lets also have a workflow for prototyping modules.

You are quite correct that the hardware is quite capable of handling this frequency measurement task with ease.

The issue is the .Net Micro Framework. If you are willing to forgo .Net and program directly to the chip in C, you can get the job done.

What s not as simple or easy is to combine the use of .Net with native code and direct control of hardware interrupts etc. It may very well be possible, and I hope you succeed as we would all like this capability. You should be prepared for some setbacks along the way.

Can an Atmel AT91SAM7X512 microcontroller support the functions of the Taos TSL235R?

I am still not convinced that I need to throw more components at this problem. Netduino has an ARM7 48MHz processor- why should we deny that there is plenty of speed right on this development board? If I were to remove the processor from the Netduino and program it directly, or remove the .Net firmware and run C/C++ on it, I am sure that this sensor would run fine. I've read in these forums that version 4.1.2 of the Netduino firmware is supposed to offer run-time native code interop. I've also read about someone's project called "Fluent", which runs code something like 20 to 30 times faster than the managed code. I've also read that you can run FreeRTOS on the Netduino platform. Can't you run a quadrocopter with FreeRTOS? Isn't that real-time?

Does version Netduino 4.1.2 have runtime native code interop? If not, when will it have this functionality? Where can I get this "Fluent" project? Where can I find resources on how to run my own C/C++ on this board?

I understand the opinion that more tools will help me solve this problem, but I would rather use what I have instead of having to then deal with connecting, learning, and powering these other pieces.

Thanks,

Nick

As others have pointed out, a Netduino is not the right tool when you require precise real-time programming. There are however lots of cheap micro-controllers that can measure frequency and report the results to the Netduino via I2C or many other ways.

One cheap way to do this is with a TI MSP430 board which only costs $4.30 delivered (https://estore.ti.co...-kit-P2031.aspx ) This is probably the cheapest way to do a one-off project and the TI chip has reasonably good support.

The best way to look at this is that there is no one perfect single board computer. The key is to use one appropriate to the task and remember that they are cheap enough that you can break the task down and use more than one board.

Sneak peek inside the lab...

When we build new products, we usually spend about 6-9 months: design, parts sourcing, testing, building test jigs, etc.

To make Gadgeteer affordable, we needed to make our own plastic sockets for Gadgeteer accessories. [These sockets are drop-in replacements for the normal, more expensive sockets. You'll also be able to make your own boards and accessories...all open source.]

We just received the first batch of sockets, so I took a photo of a handful of them.

Now we'll do temperature testing (to make sure they survive the industrial reflow oven) and hand-assemble a few prototype boards.

BTW, a big thank you to the MSR team in Cambridge for their work on Gadgeteer (past, present and future).

Chris

Disclaimer: We haven't officially announced a Gadgeteer product lineup... We do sometimes cancel projects. But I thought I'd share a sneak peek update since you have shared your enthusiasm about Gadgeteer

Chris,

I was looking at the specifications for the connectors used by the .Net Gadgeteer and I see they are rated for an average life of only 500 insertions, which seems incredibly low.

What is the MTBF for your connectors?

We actually did a bunch of engineering on a SAM9G45-based open-source Gadgeteer mainboard. Basically, we offered to create a $99 open-source Gadgeteer mainboard, an open-source NETMF port for SAM9G45, and a bunch of open-source Gadgeteer accessories if MSR would open-source the Gadgeteer software. They worked hard on that and were able to open source the smaller core but unfortunately they didn't have the engineering resources to write all the Gadgeteer drivers.

So they felt that they needed to launch Gadgeteer with a closed-source partner. So we had to scrap a ridiculously awesome board.


Chris

Is/was your mainboard similar to this: http://www.armkits.c...CFdU55QodtTGCMw ?

With a new release of Fritzing (0.6.2) just released, I thought it would be a good time to bump this thread. I just downloaded the new release, and (like before) it is great to have all three variants of the Netduino in there "out of the box". A big thank you to those who made it possible.

Fabien, have you done a blog post or writeup on this? This is great information.

The detachable board on the STM8S has the necessary decoupling capacitors and features a 16 Mhz quartz for precision frequency counting / generation. Does the ProtoModule include a resonator or a quartz as well? For reference, here is the STM8S, detached from the STLink interface, with a Go! connector soldered to it:

This sounds like a marrage made in heaven Dan. Using the discovery board as a programmer for the proto module seems like a cheaper and more flexible solution rather than buying a separate programmer. Would you be willing to provide more details on your configuration?

I've attached an image of a bare PCB next to the discovery board. Note that the actual prototype area on the discovery is the parts below the routed slots. The part above those slots is the ST Link programmer, which is what I connect to the SWIM connector to program the chip on the protomodule.

I have somewhat of a mixed background in that I am a radio amateur (ham radio) as well as working as a programmer all my life.

In reading this thread (and lots more like it on other forums) I believe that often times people overlook that there is a big difference between knowing enough to get something to work and thoroughly understanding it.

Consider changing the oil in your car. That is something most people can do without an understanding of how an internal combustion engine works. By the same token there are some basics that one needs to know in order to do it safely and not ruin the engine. Things like "Shut the car off before crawling underneath to drain the oil" and 'Be sure to check the oil level on the dipstick before restarting the car and then check for leaks."

Now consider a simple electric lamp. One needs to have a power source, a lamp and some wire to connect them. One does not need to understand the difference between AC and DC current, or for that matter even care.

A good electrical engineer will understand Maxwell's equations, just as someone with a degree in computer science should thoroughly understand design patterns. That having been said, I know lots of people making a living as a programmer could not implement a state machine if their life depended on it.

The plain fact is that for _most_ of the things that beginners want to do with single board computers, knowledge of graduate level engineering is simply not required. What is helpful is the level of knowledge typically required to earn a boy (or girl) scout merit badge. Much of what one needs to know is best learned in a group environment with hands on labs. One could take EE courses at a university or one could simply go to a local hackerspace and learn by doing, benefiting from the experience and knowledge of others.

For those wanting an on-line resource to gain greater exposure to basic EE, two sites I have found helpful are the EEV blog and The Signal Path. If you are rusty on the math or other academic topics (like differential equations) the Khan Academy is a great resource.

Just keep in mind that learning electrical engineering and building simple projects are not always the same.

Finally allow me to say something to the EEs here. For a programmer who already knows C# (or VB) an .Net the Netduino is an ideal first single board computer. Why? because he already has the toolchain (Visual Studio) installed and running on his computer. While there are great, open source toolchains such as GNU on Unix available for a multitude of single board computers, for a programmer who uses Visual Studio on a daily basis that would simply be one more hurtle to getting started with micro-controllers. Similarly for a person with Unix PC who regularly programs in GCC, the Netduino may not be ideal.

Mention was made of the TI MSP430 which at a cost of $4.30 delivered has to be one best deals going. Personally if I am going to make a mistake and destroy a micro-controller I would rather make the mistake with one of my TI 430s than one of my Netduino Plus at $60. Heck, many places charge more that $4.30 just to ship a Netduino! The point being that there are lots of boards and parts available and it is usually best to try many of them and learn rather than fret over finding the one best one.

I too find this sort of project fascinating. Thanks in advance for whatever details you choose to share with us.

The issue only has 2 votes on Codeplex! Go and Vote! (you might have to create an account)

http://netmf.codeplex.com/workitem/754

-Valkyrie-MT

I just made it 3.

Have you considered measuring magnetic field?

Hi Mikeo2721,

I wear out a USB port on my computers just about every year. They're rated for thousands of insertion cycles--but it's amazing how many times I unplug/plug things around here testing engineering samples, etc.

Anyway, let's make sure we get you up and running...

Chris

Chris, If you wear out a USB port on a motherboard that can be an expensive fix ;-)

Have you considered using a USB extension cable (male on one end, female on the other) and leaving it plugged into the PC continuously? That way it would be the extension cable that would wear out, not the socket on the PC.

The issue is that, if switching off the whole board, the Netduino wouldn't be able to wake up on time for the UI to flow nicely.

Have you measured the total time for your application to start from a cold boot? I am curious as I would have thought that it would be possible to get that into an "acceptable" range.

As for handling the keyboard and display, why not use a really low power chip (like perhaps the $4.30 TI MSP430 board) to handle that and cause the Netduino to boot as required (like when a key is pressed).

I just got around to fooling with this and it isn't clear (to me) how to interface this to the Netduino. The video mentions interfacing the the USB but there are no details. I suppose I can look at their SDK but I believe it is C++ and would require some port to Netduino.

Has anyone actually interfaced this to a Netduino?

The easiest way to interface the TI chip to the Netduino is via the TTL level serial port, both boards have them.

Another option is to get a good used analog oscilloscope, I picked up a used Tektronix 100 Mz dual channel unit that is absolutely top quality. If you shop around you should be able to find one for $100 or less, often much less. Look on Craigs List and E-Bay. It is best if you find one locally as they are big, heavy and easily damaged in transit if not packed properly for shipping. Plus if you buy locally you can verify that it works before handing over your cash. I have heard of many people who were poor students without much money who have asked around and gotten used scopes for free, although that route will probably take you longer. Good luck!

Here is a post you may find helpful: http://www.faludi.co...sensor-circuit/

Basically the way it works is that the resistance of wet soil is lower than that of dry soil. You could either make your own probe or hack one of the cheap probes from a garden supply shop.