I'm looking at a device that runs at fast-mode 400kHz i2c. Is it possible to integrate with Netduino?

I am trying to determine how to get accurate color representation of RGB values with a Netduino's PWM inputs. Specifically, I had worked with an Arduino and the range of the PWM inputs was 0 to 255. On the Netduino, the range is 0 to 100. I want to be able to generate colors based on a scale of 0 to 255 for red, green, and blue. I was able to do this easily with the Arduino. You can see my video of RGB LED color generation with an Arduino. I am unsure how to do this with Netduino. I know that there is a SetPulse and SetDutyCycle function, but I can't seem to figure out how to get a range of 0 to 255 so that I can represent monitor RGB LED values. Any help is greatly appreciated.

Is it possible to boot an install of Linux with the on-board microSD card? Can I "auto-boot" Linux when the SD card powers up? I want to be able to run Linux on the microSD card so that the Netduino would basically become an MCU running Linux and I could then communicate to the Linux install from C#. Is this possible?

.

.

I am converting a project from Netduino to Netduino Mini, and I have a device that requires 3.3V power. Is there a 3.3V pin on Netduino Mini so I can power this device with the Mini? Thank you

Hi Nickduino!...First off, I DO NOT want to start any other ambiguous discussion, or something like that!
I am sooooo happy that you have found satisfaction by realizing your goal.
I would only point that by using the Input Capture, you should able to reach a counting much faster. That's because it is NOT the program that counts, but the hardware itself: the program has only to read the counter value.
The Input Capture stage is also present (named as TC) in the Atmel's chips, such as the AVR and ARM (the Netduino's). By hacking the Netduino firmware you will also able to take advantage of the TC section.
However, what I wanted to say in the previous post is that the project is much faster to realize having an extra microcontroller, as your PIC.
Again, happy to read your success!
Cheers

Thank you Mario!

Anyone know where I can get a netduino t-shirt?? I use this mcu so much I'd like to show my support. It would be a nice supplement to my Sparkfun sweatshirt.

I've decided to dig in to PIC32 programming in order to get full 1Hz to 1MHz display resolution from my TSL235R light-to-frequency sensor.

Hi! I bought a 3.7v 1000mAh single cell LiPo battery and a LiPo charger/boost converter (http://www.sparkfun.com/products/10300), but I don't understand how I can wire the LiPo battery to my Netduino Plus. Can I connect the LiPo battery to VIN and GND? Since I am only getting 5V from the battery, I don't think VIN and GND will work. Where do I plug in the battery to power my Netduino? Thanks! Nick

Thanks CW2!!

Could be a problem with the SD card... I'm re-formatting it now. I don't have a second one around to try. Perhaps the issue is more related to my code and what I am doing. I am reading a file off of the SD card via a Filestream, and then I am sending the data out onto the Netduino's UART to another device. I am sending it at 1024 bytes at a time, but I wonder if I am running into speed issues because of the fact that I'm re-assembling it for transport onto the UART. The other device also then has to process it. I'm not sure where the bottleneck is. I'd like to think it isn't my code, but that's also possible.

I have a 2gb microSD card that I pulled from my Blackberry and I plugged it into my Netduino Plus, and I noticed that it is very slow to read files. It is even slow when using a USB-to-microSD card reader. I am comparing to the speed of a standard USB drive. Are USB read times normally faster than microSD, or am I doing something wrong? Is there a way to read USB drives with a Netduino, i.e. with a compatible USB shield or something? I need faster read times somehow. Even a 20kb file takes too long.

I've been advised that I can create a "super-interrupt" pin on the Netduino by hacking the firmware. Please see quote from Chris Walker below:

...make that pin an FIQ-accelerated pin...and then use an FIQ handler in your code to count the number of pulses. Then you can easily create a "startcount" and "StopAndGetCount" managed code method to capture the values. FIQs will activate in less than one microsecond, will supercede the .NET MF runtime and...as long as they're quick...will not interfere with your code. We're using them for software PWM in an future update of the firmware, for instance.

Chris et. al,

How do I start with getting this set up? I downloaded the .Net MF Porting Kit and the Netduino Plus firmware, and I've copied the Netduino firmware into the Porting Kit directory. Now I need to know how to modify the firmware to get this operational.

Hi all, I've been playing around with controlling RGB LEDs with my new Netduino Plus. I set up a server on the Netduino that listens for requests on Port 80. Then I built a web page with a color picker control that sends commands to the Netduino. The web page runs on a separate web server on my laptop. The Netduino parses the commands into individual R,G, and B values for the LED. I am using a common anode RGB LED from Radio Shack, connected to three PWM inputs on the Netduino. Here's a demo: I am trying to get a better algorithm for the color generation. Right now I am using SetDutyCycle, but I think the SetPulse method would provide even better color generation. If anyone wants to look at the C# project and maybe help me with the color generation code, just let me know and I will post it.

I guess I'm going to be forced to try this on my own. I will let you know the outcome.

I need to deploy some C# code onto two Netduinos but each Netduino requires different code. Is it possible to connect both Netduino's, at the same time, to a single laptop via two USB ports on the laptop? In C#, will the device name change from "NetduinoPlus_NetduinoPlus" to NetduinoPlus_NetduinoPlus_1" or something so that I can select which Netduino to target?

Yes, exactly. You can also rename one of them to something more permanent by using the Target > Configuration > USB option in MFDeploy.

For instance, you could name one "NetduinoPlus_PeanutButter" and the other "NetduinoPlus_Jelly". [Bonus: if they ever become sentient, they'll already be friends...]

Naming them is probably the best option...because them it won't matter which order they're plugged in...Visual Studio will always recognize them by their custom names.

Chris

Excellent. Thanks again, Chris.

Thanks Nick F. for the quick response. I will take a look at the breakout board version as soldering is not my specialty.

In general how was your experience working with this device? Are there any other components that you used for your implementation? thanks again.

mattnet,

I've had great success with it. My Gainspan post should help. There is example C# code which has helped others get up and running quickly and I also put up a video example of ad-hoc Wi-Fi communications between two Netduino's with Gainspan modules.

Just a word of caution: if you want to update the firmware to the current version, you will need to sign a non-disclosure agreement with Gainspan in order to get the current firmware files. However, the device works fine out of the box without a firmware update. I updated my firmware to take advantage of the ad-hoc DHCP server functionality.

Besides wires, there are no other components required, unless you want to update the firmware, which requires a USB-to-UART 3.3V adapter. Check out my post for all the details.

You'll still need to do some soldering to get wires connected to the breakout board holes, but it is not difficult.

Nick

Coincidentally, I just finished reading the "High resolution light measurement" thread. Glad you decided to go with the i2c lux sensor. Netduino + i2c has kept me pretty happy and I always lean toward i2c options when shopping. The MinM is another example of super-convenient micro-controller/i2c overkill. It combines LEDs and an ATtiny85 micro-controller on one little board. I bought three for a project and it was ridiculously easy to interface and control them via i2c. Sure, my silly little project ended up with a total of 4 microprocessors, but it was orders of magnitude easier than trying to do everything directly with the Netduino.

Anyway, that thread was a good read. I think I might actually try out TI's "MSP430 LaunchPad Value Line Development Kit" mentioned in one of the posts. There is at least one thing I've wanted to build on top of Netduino that would benefit from offloading some of the high frequency work onto an auxiliary controller.

One other thing... You might want to check out the I2CBus classes by FusionWare and Phantom Typist -- they're in other threads in these forums. If you write your TSL2561 code as a "driver" for one of these bus classes, it might save you a little bit of time and also help if you ever want to hook up another i2c device at the same time as the TSL2561. Others have posted I2CBus compatible code back to the forums for others to benefit from, which was a huge help for me when I was starting with Netduino and i2c.

Good luck with the project.

I am still on a quest to build an accurate lux/foot-candle meter using off-the-shelf components. While it was frustrating at times, the high frequency light measurement project was a great learning experience for me, and now I understand that it is not bad practice to use additional chips in my projects. I have that TSL235R sensor working fine now. To get it working, I ended up writing a frequency counter for a PIC18F252 and then sending the measurements from the PIC18 to the Netduino via UART. I compared the PIC18 frequency readings against measurements right from the sensor using a high-quality o'scope, and my frequency counts prove correct.

The current problem is that the TSL235 sensors measure outside the visible light spectrum and there is no simple way to calculate the intensity of only the visible spectrum. The TSL2561 presumably solves this by providing a way to "subtract" the non-visible spectrum so that I am only looking at the intensity of the visible spectrum.

My intro to microcontrollers began with an Arduino and BlinkM i2c RGB LEDs. You're right, not to mention being really expensive, those LEDs are i2c overkill, but for me they served as a great intro to i2c communications.

I'll be checking the forums for those I2CBus classes.

The Gainspan GS1011MIP is $69.99, for the breakout board. I use this module with the Netduino.

If you're good at soldering and figuring out schematics, you can get the GS1011MIP module itself for $33.95.

Hi,

I am working on connecting a TSL2561 lux sensor to a Netduino. It is an i2c device.

Can you please take a look at the Arduino wiring diagram and let me know if I can do the same wiring to a Netduino?

Do I need to add any pull-up resistors or can I wire as shown and expect it to work?

The wiring diagram looks good to me, for Netduino. Note that the two small black surface mount devices labeled "103" are 10K resistors. These seem common as pull up resistors on i2c breakouts. The schematics for the product are available, but you'll need Eagle to view them. I've included a screenshot, below. Note that the 10K resistors are being used as pullups for SDA and SCL.

Thanks Spork. I figured the pull-ups might be in there already, but didn't notice that there were Eagle schematics available.

Now I just need to convert the C++ code to C#

Hi all, I am using some small LEDs for a project, and the goal is to create a small light fixture. I am trying to find a good material to use to diffuse the light from the LEDs. I have looked at theatrical gel filters, but these are flimsy and impermanent. Is there a way to use a piece of Lexan and coat it with diffusion material? If so, what diffusion material would work best? Or is there some kind of plastic like Lexan that already has a suitable diffusion coating? Any help is greatly appreciated! Thanks!

I actually bought this the other day: http://www.sparkfun.com/products/10300, along with this cell: http://www.sparkfun.com/products/339. Do you know if the Power Cell - LiPo Charger/Booster will allow me to keep my project plugged in while also charging the lithium battery? I couldn't find a clear answer on that. I don't want to have to remove the battery and unplug my Netduino in order to charge it.