-=> Quoting Robert Osborne to Rick Collins/all <=-
 RO> What about externals?  How are they configured for comm port and IRQ. 
 The beauty of external modems is that you DON'T need to configure
 port address and IRQ... it uses your EXISTING serial port... Which is
 good if you are like me, who likes to tinker with all kind of combos,
 I uses USR Courier V.E but feel that the internal modem looks a bit
 weak on the serial port side... and plus, I don't get to see all those
 light shows... so I got a USR Courier External, and then a Hayes ESP ][
 card... was stuck deciding between Telcor's and Hayes'... then go for
 Hayes cuz they can allow higher speed, much higher speed...
 RO> Are all UART chips clearly marked with the 16550 or 8250 designation?
 RO> Or do you have to go look for a manufacture's specific code for his
 RO> chip?  If it is an external modem, do you have to buy a special serial
 RO> board to handle the extra speed of the 16550?
 Most of them will tell you on the chip... however, with those highly
 intergrated cards and motherboards, the 16550 chip is only a TINY part
 of the chipset, and you are not likely to find anything like a note saying
 "this chip contains 16550, 3452, 36573, 146723, and more"... :)
 I recommand that you find some software to see if they can detect it...
 The SIO High Performance Serial Port driver I use for OS/2 can detect those
 stuff well... BUT... it is only for OS/2, but I'm sure you can find
 other stuff for DOS and other OSes...
 If you want to upgrade from 8250 or 16450 to 16550A... just pop the chip
 out and off you go...
 RO> While we are talking about speed, I see that there is a lot of traffic
 RO> on the board about setting the speed of their modem.  I though that
 RO> the newer modems, 14.4 and above could all auto adjust to what ever
 RO> speed the answering modem first transmitted at, if they could attain
 RO> that speed.  Other wise they shifted to a common lower speed?  How does
 RO> this work?  Do you have to software set your speed to some upper limit?
 Nope, the modem does all that... AFAIK that it is ALWAYS the case that
 at least one side can understand the "hail", ie the slower "hail" is
 going to be understanded by the faster modem, than the faster modem will
 communicate to the remote modem with the protocal that the slower modem
 can understand...
 This is only my GUESS... anyone know better (there should be a lot of
 people) are EXTREMELY WELCOMED to correct me...
 RO> I also thought that there is some limiting speed over the
 RO> communication media being used.  Ie 28.8 was the upper limit for
 RO> telephone lines? Maybe higher for cable lines or fiber optic.  Is it
 RO> also not true that the newer modems don't really transmit at higher
 RO> rates, but instead compress and decompress the data on the fly to
 RO> obtain faster rates of data thru put?  When did they start all this and
 RO> at what modem speed did compression take place?
 the Max speed (RAW) I have attained with my Modem is 46,666 bps download,
 and 33,600 bps upload... this is done by some Wiz who found out about the
 one way digital signal transmission...
 RO> There is also some specifications that deal with error correction and
 RO> being able to recognize compressed data?
 V.42, and V.42bis
 RO> Would you please elaborate some on any of these subjects.  Or suggest
 RO> where I might obtain referernce information that discusses this in
 RO> detail.  I would like to better understand  the various modems that
 RO> are out there and what is coming in the future before i make a decision
 RO> on purchasing one.  Do you work for one of the modem companies?
 Keep reading this echo, and you shall become an EXTREME MODEM EXPERT...
 I'm trying to become one... :) But still have trouble with Rockwell modems
 (can't get my hand on one I like... the DSP one... :) )... or those gutless
 Winmodem... which I DON'T want to touch...
... Veni, vidi, Vulcan: I came, I saw, I shoot.
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