I'm just starting out on a access control system project and should appreciate
any pointers and ideas ...

The overall concept is for a distributed system with standalone readers
interconnected over a multi-drop RS485 network.  A PC will maintain a
database of users, access levels, etc.  The database will be downloaded to
each remote (PIC-based) reader unit when changes are made.

Each remote unit will allow a choice of proximity reader, Dallas touch
memory reader or magnetic swipe card reader to be used.

Specific questions are:
1) Any advice on or experiences with proximity token components?  TI TIRIS
components look interesting.  Also (Finnish company) Idesco.  Has anybody
written code to interface these readers to a PIC?

2) Does anybody have code to read Dallas Touch Memories from a PIC?
This question must have been asked before.  However, I have checked the
Dallas Web site and generally looked around without success - I'm probably
just not looking in the right places!

3) Any ideas on recommended components (and code for) magnetic strip card
readers?

4) Any ideas on the best component to use for storing data in the remote
units? Non-volatile storage of roughly 12k bytes will be required.

Thanks in anticipation of your help.

Doug