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Monkey4sale
02-10-2007, 12:59 AM
I have recently entered a competetion where the goal is to build a electronic device, and the one that came to mind was a RFID operated lock since they have them all over the school i go to and should be fairly simple to build.

But since im on a tight budget i figured·i should look for something other then the parallax design, i came across a "ID12 RFID Reader Module" at http://www.rfidshop.com/index.asp?function=DISPLAYCAT&catid=240, and i figured that it should fit my needs just fine.

But since im failry new to electronics i was wondering if it was possible to hook it up, i figure it should be since it needs 5V regulated which the board already does, and it needs 200mA which is also the same, so as long as i hook it up right it will work for an RFID reader right?

It reads at 125khz which the parallax cards work, so as far as i can tell it is the perfect thing for a door lock.

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When you see the pretty smoke come from a component. It is time to go shopping again.

Mike Green
02-10-2007, 01:11 AM
As with anything discussed here, one of the things you get when you buy from Parallax is excellent support. They will either help you to get it to work or refund your money (and they prefer that it works ... someone else may want to do the same thing you do and they'd like to know what it needs).

That said, I looked at the on-line documentation and it ought to work as you (and the documentation) describe. It needs 5V at a current that the Stamp development boards with a regulator can supply (like the Super Carrier or BOE). It seems to talk logic level serial I/O which the Stamps know how to do. Good luck!

Monkey4sale
02-10-2007, 01:42 AM
so wait, My understanding was right? thats a first.

From the little bit i read about the parallax reader it uses the 12-byte ASCII structure, but what does this mean?

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When you see the pretty smoke come from a component. It is time to go shopping again.

Post Edited (Monkey4sale) : 2/9/2007 6:51:45 PM GMT

Franklin
02-10-2007, 02:21 AM
If you're not using the Parallax reader what difference would that make? There are documents on the rfid reader online at Parallax.com you could start by reading those.

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- Stephen

Mike Green
02-10-2007, 02:33 AM
You'll have to figure out the meaning of the description of the data format returned by this RFID reader. It seems to be in some kind of standard "Weigand26"? You'll need to do some research on the Internet to find out what the various bit and bytes mean.

Chris Savage
02-10-2007, 03:02 AM
Monkey4Sale,

The RFID Reader you mentioned does operate @ 125 KHz, but frequency isn’t everything…There is a unique protocol to the tags/reader and yours specifies EM4001, whereas ours specifies EM4100. Another different is yours refers to 64-bit ID whereas ours is 40-bit I believe. These are all things to take into consideration when choosing Cards/Readers that match up. I hope this helps. Take care.

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Chris Savage
Parallax Tech Support

Monkey4sale
02-10-2007, 04:15 AM
well the bits is how many digits are on the card, right? but does the encoding mean i can only use EM4001?
What all is compatable with EM4001?

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