I thought I knew basically how the rolling code keyless entry systems
work: the transmitter and receiver generate matched pseudorandom
sequences, the receiver has to look several codes foreward of the
current code in case someone hit the button while out of range, etc.

My question is how do they handle multiple transmitters?  My wife's car
has two transmitters and one sits on the shelf for months on end, but
both work.  Does the receiver have to know there are multiple
transmitters out there and keep track of pseudorandom sequences for
each?

Sherpa Doug

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