feature request

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A.J.Scholl@markov.dur.ac.uk wrote:
> One interesting difference in the UK is that caller ID information is
> apparently sent *before* the first ring, so any modem which
> understands UK-style caller ID must be listening to the line all the
> time.... I haven't seen one, though.

Not quite. There is a 'line reversal' where the voltage of the line gets
reversed shortly before the caller id burst, shortly before the big AC
ringing signal gets sent. Therefore the modem only wakes up and listens
to the line when the polarity gets reversed.

This means it doesn't accidentally start trying to decipher voice on an
extension line as data, or try to negotiate noisily with your ear.

-- 
Simon Hewison