da Silva, Joe wrote:
>
> I think, a better way to avoid confusion, is to use the
> RS-232 prefix when talking about RS-232 connections,
> and PSTN (or similar) prefix when talking about the
> RJ11 (or whatever) analogue connection to the wired
> telephone system. Incidentally, it doesn't actually matter
> if you cross your (2 wire) PSTN connections - all PSTN
> equipment is [supposed to be] polarity insensitive. Also,
> the modulated signal works the same, regardless of
> phase reversal.
Correct, re: the polarity reversal, and I agree re: RS232.
I didn't notice the following:
> > Clarence,
> >
> > Not to be picky, here, but lest we somewhat confuse ourselves, the
> > cable used to connect external modems (or Internal modems, for that
> > matter) is a two-wire telephone hookup wire...has no crossing or
> > uncrossing....just like the radio connection which will be used by
> > Michael's cellphone.
I didn't think I had to explain myself on this point. I believe I said:
"The 'crossing' takes place in the modem" ? Also enclosing "crossing"
to indicate it was just a descriptive term ?
Obviously the modem separates the received modulated carrier from it's
own transmitted carrier and sends the received data to where the normal
computer looks for it - on the rcv data pin of an RS232 connector or
the rcvd data register of an internal uart/modem. <G>
- Clarence Verge
--
- Help stamp out FATWARE. As a start visit: http://home.arachne.cz/
--
