Re: Cause of some major X10 problems found

[ddl@danlan.*com (Dan Lanciani)]

In article <sjxFi.526260$p47.277528@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>, JeffVolp@xxxxxxx (Jeff Volp) writes:

| It may be near zero, but I have documented on my logic analyzer that it can
| happen.  You may remember an earlier post regarding beating compact
| fluorescent lights producing peaks and valleys similar to a X10
| transmission.  I found that about 2 minutes after I switch on my CFL "noise
| generator" the beat frequency between a couple of the bulbs gets low enough
| that the peaks and valleys occur on alternate half cycles.  If the receiving
| module just happens to catch enough noise 3 times in a row to recognize a
| start pattern, the remainder of the message with alternating 1-0's does get
| through as a valid command.  Even with the enhanced error detection
| requiring complimentary 1-0's, I did capture one squeaking through.

Also, traditional X10 (brand) modules fail to check (IIRC) one slot for
correct complementary coding and third-party products may fail to check
even more (original Switchlincs missed two).  So there is a little wiggle
room.

				Dan Lanciani
				ddl@xxxxxxxxxx