To get back to this issue, I've tested Colin's 3 source files he posted above on the Netduino Plus 2, and it works. However, when the network is not available, an exception gets thrown instead of a false being returned.

Successful pings return a true though, so this is definitely a solution.

Hi,

We're in desperate need of someone who'd be willing to rewrite code for the WiFly RN-XV module. What we're using just isn't working reliably and we've already sold it to the client.

We're willing to pay between US$1000 - US$1500 for the help, depending on how quickly you can do it. We're looking at between 1-2 weeks.

All we're trying to do is scan networks, connect to the strongest AP and post some data to a webpage (which has already been developed).

We're using the netmftoolbox framework for the WiFlyGSX model but we've hacked it to get it to do what we want, but unfortunately we're obviously doing something wrong. Problems being experienced includes sudden unresponsiveness from the module (which looks like a communication issue) and serial exceptions left right and center. The idea is to just re-write a simplified version of what we need it to do and thats it.

Any takers? This is really urgent. If you can do it after hours thats fine, as long as we meet deadlines.

Thanks

Hi,

What options are available to store data besides the SD card? Is it possible to hook up an extra eeprom to the ND2+ to access and write to it's memory?

The data will most likely be hour meters or something simple, so in other words I don't expect to use it as a buffer stream or something that i write to constantly.

Any (tried and tested) ideas would be great! Thanks

The code was for PC with the module attached to kind of a USB to serial converter so it might actually be of pretty limited use to you. Also, I just made a few simple tests, basically only detecting tags coming into the field but I'll try and dig it out for you.

This is the one I was using:
http://www.sonmicro....id=57&Itemid=70

Which module are you using?

So you haven't used it on a Netduino yet?

I'm going for this one: http://www.elechouse...roducts_id=2156

Hopefully I can figure out these damn hex commands...

 

I've played around some with the SM130 Mifare module from SonMicro and didn't have any problems. Maybe that's not the one you got though.

 

In general hexadecimal formatting is merely used as a notation on paper and in programming languages. If you write 0x80 in C# (and C/C++) the actual value will be 128 decimal as it would if you wrote 128 in the first place.

 

In C# you can use hexadecimal notation freely so you should not need any conversion - unless of course the hexadecimal notation is in a string, then you need to convert it.

 

For single bytes, this can be done quite easily back and forth using (in analogy with the above example) 128.ToString("X2") and byte.Parse("0x80", NumberStyles.AllowHexSpecifier) functions respectively.

 

I don't know of a smart way to convert whole strings, but you could of course always traverse the array and assemble a string as you go using the mentioned functions.

 

This methods below are supposed to translate byte arrays into strings with 8 bit space separated hexadecimal numbers and vice versa. This is from the top of my head so you may need to alter it a bit if it does not compile as is:

public class HexConversion{   private static string _hex = "0123456789ABCDEF";   public static string toHex(byte[] 

{ string s = ""; for(int i = 0; i < b.length; i++, s += " ") s += _hex[b[i] >> 4] + _hex[b[i] & 0xf]; return s; } public static byte[] fromHex(string s) { string[] a = s.Split(' '); byte[] b = new byte[a.Length]; for(int i = 0; i < b.length; i++) b[i] = byte.Parse(a[i], NumberStyles.AllowHexSpecifier); return b; } }

It could be you need to add the "0x" prefix in both the functions above. You would then use these functions like so:

// convert a regular string to a hex stringstring hex = HexConversion.toHex(Encoding.ASCII.GetBytes("Hello world"));// convert a hex string into a byte arraybyte[] bytes = HexConversion.fromHex(hex);// convert a byte array to a hex stringhex = HexConversion.toHex(new byte[]{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15});

Hanzibal, is there a chance you could share the reading and writing code for the SM130 module? I think I might go with this if I have some proven code to go with... thanks!

Hi there,

After using the 125khz readers on the Netduino, I decided I want to write data to the tag, which forces me to use 13.56khz tags (Mifare) and appropriate reader/writers.

Initially I bought a NFC shield, which was a disaster because I couldn't get the SPI driver to work with Netduino. I've read multiple threads about it and no-one has been able to get it right with a Netduino. So I decided to get a new reader/writer using UART comms instead.

The problem is that the UART commands are all in hexadecimal format and I don't have much experience working with hex conversion into bytes to send over UART...

So a few questions before I start:

[*]If I wanted to send 0x01 as a command to search for cards, could I simply do this? serialPort.Write(Text.Encoding.UTF8.GetBytes("0x01"), 0, theLength);
[*]If I needed to encode something as hex, such as string or number (i.e "Hello World", or "12345"), how do I do this? Is there a library or method extension out there I can use to convert it?
[*]At a first glance, would this reader/writer work with the Netduino 2? I see it uses a 4-pin wire, but I can just put in some solder wire tips and connect it to the headers: http://www.elechouse...roducts_id=2156
[*]If I have 1k space on the Mifare Card, how can I calculate how much space "Helllo World" or "123456" would take in hex format on the card? I'll have a few variables i want to push into the card so I need to make sure it will all fit.
[/list]

 

I'd REALLY appreciate some help, it's for a project at work and I need to make sure of my facts. Thanks a ton!

Hi,

Since I reside in South Africa, personal security is a big concern. I've decided to rather spend $500 on a Netduino solution instead of paying a monthly fee of $50 to a security company. I'm now in the design phase, so I'm considering the various challenges and requirements ahead.

So far I've identified the following requirements:

• Indoor motion sensors for each room (3-4 rooms)
• A loud speaker in the ceiling
• A bright alarm light outside
• An activation/deactivation interface

I live in a cul-de-sac - I'm very well acquainted with all my neighbors and we're always on the look out for each other. My idea behind this system is not so much armed response but more of a 'scare away' tactical approach. I suspect the audible alarm and visual light will be sufficient enough to deter intruders.

When I consider that the motion sensors use analogue signals, the first challenge I can identify is the distance between all the sensors and the central Netduino. I would guess the average distance between each sensor to the Netduino would be around 15 meters. I can only imagine that I'd suffer from noise and loss of signal issues between the sensors to the Netduino.

I've considered using an XBEE approach, but what other alternatives are there?

As for the siren and light, I'll just use external power with a relay to get them going.

Is there anything I've overlooked here? I've got a bunch of nice toys lying around such as the Nwazet Go kit with touch screen, a GPRS shield, couple of Netduinos, sensors etc.

Where to now?

Daniel

--

P.S: I've got a Kinect, and some exposure playing around with the SDK, could this influence my decision? Hmmm...