11 replies to this topic

[MrSmoofy]

My appologies if there is a thread for this already but it seems the forum search is broken at the moment (I've reported it) I'm new to this kind of hardware but not to software development. So I'm wondering if there is a RFID shield? (Are the attachment boards called shields?) Would love to get my hands on this if I could read RFID's with it. Thanks

[JohnH]

My appologies if there is a thread for this already but it seems the forum search is broken at the moment (I've reported it)

I'm new to this kind of hardware but not to software development. So I'm wondering if there is a RFID shield? (Are the attachment boards called shields?) Would love to get my hands on this if I could read RFID's with it.

Thanks

I can't answer the shield question, but I have successfully used a Parallax RFID reader with my Netduino.

http://www.parallax....14/Default.aspx

Radio Shack had this one on clearance for $8.97.

Here's my test code...
(You'll need to add a reference to Microsoft.SPOT.Hardware.SerialPort to get this to work)
(Connect the RFID reader output pin to digital pin 0 on the Netduino)

SerialPort SPort = new SerialPort("COM1", 2400, System.IO.Ports.Parity.None, 8, System.IO.Ports.StopBits.One);
SPort.ReadTimeout = 1000;
SPort.WriteTimeout = 1000;
byte[] buf = new byte[12];
string CardId = "";

while (true)
{
int readcnt = SPort.Read(buf, 0, 12);
if (readcnt == 12 && buf[0] == '\n' && buf[11] == '\r')
{
for (int i = 0; i < readcnt; i++)
{
if (buf[i] != '\n' && buf[i] != '\r')
CardId += (char)buf[i];
}
if (CardId.Length == 10)
{
Debug.Print(CardID)
}
}
}

Hope this helps!

[MrSmoofy]

I can't answer the shield question, but I have successfully used a Parallax RFID reader with my Netduino.

http://www.parallax....14/Default.aspx

Radio Shack had this one on clearance for $8.97.

Here's my test code...
(You'll need to add a reference to Microsoft.SPOT.Hardware.SerialPort to get this to work)
(Connect the RFID reader output pin to digital pin 0 on the Netduino)

SerialPort SPort = new SerialPort("COM1", 2400, System.IO.Ports.Parity.None, 8, System.IO.Ports.StopBits.One);
SPort.ReadTimeout = 1000;
SPort.WriteTimeout = 1000;
byte[] buf = new byte[12];
string CardId = "";

while (true)
{
int readcnt = SPort.Read(buf, 0, 12);
if (readcnt == 12 && buf[0] == '\n' && buf[11] == '\r')
{
for (int i = 0; i < readcnt; i++)
{
if (buf[i] != '\n' && buf[i] != '\r')
CardId += (char)buf[i];
}
if (CardId.Length == 10)
{
Debug.Print(CardID)
}
}
}

Hope this helps!

Thanks, this is a good start but I will be wanting something much smaller.

[Chris Seto]

How about this? http://www.sparkfun....roducts_id=8709

[greg]

How about this? http://www.sparkfun....roducts_id=8709

I have an ID-12 and ID-20 from Sparkfun - stupid buzzer though - you have to break a trace to shut the darn thing up.

I personally like the RedBee from RoboticsConnection (you can also get it from Trossen Robotics). It's bigger (more like a parallax) but its WAY more flexible. Even has its own C# library and is event driven. However, not sure I can integrate it with the Netduino so I'll probably fall back on the ID12 and ID20 since they are just raw serial.

[MrSmoofy]

How about this? http://www.sparkfun....roducts_id=8709

That's pretty close the size I want but on the ID-2 it says 5v and also requires an external antenna which is where I've found my issue on size. If I can find one with an antenna about the size of a quarter I think I would be in good shape as I plan on using something like the small glass tube for the tag.

[Chris Seto]

There's also this one: http://www.sparkfun....roducts_id=8628 with a built in antenna. The only issue is that uses 2mm pin spacing, but they do sell a breakout board. As for requiring 5V, the Netduino can supply that. Why is that an issue?

[greg]

That's pretty close the size I want but on the ID-2 it says 5v and also requires an external antenna which is where I've found my issue on size. If I can find one with an antenna about the size of a quarter I think I would be in good shape as I plan on using something like the small glass tube for the tag.

ID-12 is the size of a quarter but I can tell you from personal testing that glass tube tag range is pretty much microscopic. For my project I was planning on mounting glass tube tags in N-scale model railroad cars - working with the tags I can tell you it's a non-starter - they just don't have the range required to read. At most you get 1/2" and even thats under super-optimal conditions. In reality the tags have to be practically touching the reader.

However - based on your size requirement the ID12 is the right size. It measures 1" x 1" square.

[MrSmoofy]

There's also this one: http://www.sparkfun....roducts_id=8628 with a built in antenna.

The only issue is that uses 2mm pin spacing, but they do sell a breakout board.

As for requiring 5V, the Netduino can supply that. Why is that an issue?

Sorry forgive my NEWNESS I know very little about hardware and reading so far I thought everything had to be 3V because that's the max you will get out of a USB Connection.

ID-12 is the size of a quarter but I can tell you from personal testing that glass tube tag range is pretty much microscopic. For my project I was planning on mounting glass tube tags in N-scale model railroad cars - working with the tags I can tell you it's a non-starter - they just don't have the range required to read. At most you get 1/2" and even thats under super-optimal conditions. In reality the tags have to be practically touching the reader.

However - based on your size requirement the ID12 is the right size. It measures 1" x 1" square.

greg I added you to MSN we should definitly talk as it sounds like you have already been testing what I want to try to get working. I'm just a software guy so this hardware stuff is all new to me. I know what I want to do it's just I don't know if it's possible with the hardware that exists today.

[greg]

Sorry forgive my NEWNESS I know very little about hardware and reading so far I thought everything had to be 3V because that's the max you will get out of a USB Connection.




greg I added you to MSN we should definitly talk as it sounds like you have already been testing what I want to try to get working. I'm just a software guy so this hardware stuff is all new to me. I know what I want to do it's just I don't know if it's possible with the hardware that exists today.

If the ID-12 works then you'll probably want to use a breakout board and have it powered separately from USB - just use USB/serial for communication. I wouldn't want to power the RFID reader off of a netduino card - i'd rather use its power output for other things!

[Fred]

ID-12 is the size of a quarter but I can tell you from personal testing that glass tube tag range is pretty much microscopic.

You say you have the ID-20 too. What's the range like with the glass tube tags and the ID-20?

[greg]

You say you have the ID-20 too. What's the range like with the glass tube tags and the ID-20?

Not good Fred. glass tube tags just don't have the range - it's the nature of radio, size of antenna, etc. In the open with nothing blocking it you're looking at MAYBE 1/2" and that's holding it in position or moving very very slowly.