RFID

It would be nice to have AvrCo driver for RFID 125kHz proximity tagz and ID cards. HID and Indala are most popular standards, and HID is quite open.

Hello Rolf,

Building everything from the scratch, source, theory links http://instruct1.cit.cornell.e…/index.htm

EM4095 RFID chip module and open souce code:
http://avrfreaks.net/index.php…pe=project
http://www.vanka.net/rfid_devices.htm

HID corporation readers (Wiegand, RS232, USB, TTL interface):
http://www.hidcorp.com/products/readers.php
http://www.hidcorp.com/newwin.php?page_id=46

Weigand protocol:
http://instruct1.cit.cornell.e…index.html
http://www.motherboardpoint.com/t98779-wiegand-protocol.html

Wiegand interface is most used. If you make driver for it then many commercial readers will work with AvrCo, and you will not be limited to only 125kHz RFID. If I remember well, Wiegand was first used for magnetic card readers, so this is good news. Example magnetic card readers with Weigand protocol: http://www.epsys.no/mreaders.htm

I think that implementing Wiegand protocol might be the best option. It is less work and much better then implementing reader hardware on your own. With this approach AvrCo users will have access to many Wiegand compatible readers, and we will not be limited to just one type of RFID tags (or ID cards), like 125kHz I already mentioned. Even magnetic cards will be covered. If you need simple ID cards reading, you can buy 10cm range reader. If you need longer range, you will buy more expensive 60cm range reader. If you need to detect some vehicle driver key chain tag, you can buy special reader and active tags (passive are powered by reader emission, active have their own battery). It is just important to buy tags (or ID cards) that are compatible with reader. Browse upper links of HIDcorp and you will find many Wiegand compatible readers.

Everyone with AvrCo and Wiegand driver should be able to buy any Wiegand compatible card reader, connect it to AVR, and get info when some ID card is detected by reader. It is not a must, but it would be ideal if single AVR could talk to at least 2 Wiegand readers (for example, doors usually have access control for both entering and leaving, but sometimes leaving is done with simple switch, then production lines are almost always in pair...).

If I remember well Motorola Indala readers (it should be very similar), communication with reader was 2-way. You get info about ID card detected (usually 26 bits but may be higher), and then you set status leds, make sound, and command relay (this might be reader specific, I really can't remember - it was year 2001).

I used to work with Motorola Indala RFID card readers, the ones you can find PDFs at www.spica.com/products/products_ts_cardReaders.asp. They all have Weigand (Indala PXR10 was mostly used), but at the time that I used them Indala was the most expensive on the market. I can't remember the price but I can take a look if you need this info. HIDcorp used to have cheap readers and cheap cards, but I have no experience with them and I don't know what model to recommend. If you just want to support Wiegand readers then cheapest test solution might be to order simplest magnetic card Wiegand compatible reader at www.hidcorp.com/products/readers.php. RFID readers are more expensive. At www.hidcorp.com/about/sales.php?region_id=2 you can find links for german sales. Remember that with reader you will also need compatible ID cards or tags. Whatever they offer you, for driver development cheapest will do.

I am sorry I couldn't direct you more.