HI!

I've been contracted to design an inexpensive home alarm system using
miniature transmitters (inside each sending module) and a matching
receiver in the main unit. I've built a sucessful proto using Holtek 12
bit chips (8 bit address to identify the sending unit, 4 bits to
identify low battery, break-in, etc) and Ming RF modules. The customer
wants to save money by eliminating the Holteks and using a cheap 16LC54A
in the transmitter, and directly drive the 16C55 I am already using for
the main alarm syscon. I probably need to move to a chip with more rom
to fit both my alarm syscon code and a 12 bit serial code, but does
anyone have any code already written for this application? Possibly even
something similiar to a rotating code system like the Keeloq system from
Microchip?    Thanks!    Dave Miga, Electronic Design Specialists
http://www.eds-inc.com