hardware error-control, it is necessary to maintain the DTE rate above
the DCE rate. This is done so that the modem does not have to wait for
data to transmit. Serial port locking is typically an optional function
of one's telecommunications software, and the methods to accomplish it
are generally detailed in the documentation which accompanies it. As for
changing the dialing directory entries, this is done for reason outlined
above to correspond to the DTE rate, the DCE rate will be negotiated by
the modems upon connection independent of the DTE rate on either end.
CTS/RTS flow control is necessary to control the flow of data between
the modem and computer. With data being sent to the modem at a rate
which is over 2.5 times that at which the modems are exchanging data, a
method of slowing down the data flow as necessary is required.
Question: When uploading files with my new Generic Xpress, I keep seeing a message flash up on the screen which says FLOW, what is this, and what
should I do about it?
Answer: The FLOW message is a normal, non-critical indication that
CTS/RTS flow control is functioning. It is generated when the data flow
rate to the modem begins to strain the capacity of its buffer to store
data which is to be transmitted. With data coming to the modem at a rate
which is in excess of twice that which it is transmitting, it is a way
of it saying WHOA MULE! If it is annoying, it can be eliminated by
allowing the DTE rate to adjust downward to the DCE rate (typically
referred to as autobaud switching), but it comes at the expense of
throughput.
Question: I have two computers on the same phone line. Is there anyway I
can transfer files between them with the modems?
Answer: The answer is yes, you should be able to. You should be able
to just simply run a phone extension cord between the two modems, not
even hooked up to the actual phones in your house.
When going modem-to-modem, no 'MaBell' hookup is required -- at all:
1) Get a standard old telephone cable with a modular plug on each,
(like the one you use to hook a telephone to the wall jack).
2) Take one end of this phone cable and plug it into the back of one
of the modems. (Into the jack that you would normally use to hook
the modem to the wall jack).
3) Take the other end of this phone cable and plug it into the back
of the other modem. (Into the jack that you would normally use to
hook the modem to the wall jack).
____________ ____________
Like so: |\ \ / /|
| \ Back of \ / Back of / |
\ \ External \ / External / /
\ \__Modem_1__\ /__Modem_2__/ /
\ | | | | /
\| | | | | |/
~~~~~~~~~|~~ ~~~~~~~~~|~~
| |
+------------------------------+
Standard Modular Telephone Cable
Note: You can use the exact same idea with two internal modems or
a mix of an internal and external.
4) Now go to the computer hooked up to Modem_1 and load some
communications program (like Procomm, Telix, Qmodem, etc.) and
get to the terminal screen. Type:
AT
and press [Enter] to see if the modem is ready. If it responds
with:
OK
it's ready.
5) Do the exact same thing (Step "4)") over on the other computer,
the one hooked up to Modem_2.
6) On either one of the systems type:
ATX1D
This tells this local modem:
ATtention,
only give connect responses and ignore the NO DIALTONE,
and, Dial (originate the call).
7) On the other other system type:
ATA
This tells this local modem:
ATtention,
Answer the call.
That's it. Now type something -- on either. They're connected.
This document is a compilation of postings from various venues, with
credits for portions to the following:
Ted Ball Theo Irmer
Carey Bloodworth Lawrence Kirby
David Bowerman Bat Lang
Greg Bretting Dave Lyle
Les Brown Ed Mandera
Patrik Chen Bill Mayhew
Alan Clark Paul Munoz-Colman
Jan Cueleers John Navas
Jeff Derby Toby Nixon
Bill Davidsen Stephen Palm
Floyd Davidson Greg Pearson
Stephen Dunn Terry Rutter
Brett Frankenberger Stephen Satchel
Joseph Frankiewicz Tom Smith
Vernon Frazee Richard Stuart
Bill Garfield Christian Weisgerber
John Ginnane Geoffrey Welsh
Ed Hall Karl Willdig
Wolfgang Henke Mark Young
Comments and/or corrections are welcome either in the echo, Fidonet netmail,
or via Internet e-mail.
Gord Hannah Moderator
Fidonet International COMM Echo
aka:
ghannah@pris.bc.ca
--- MPost/2 v2.0a
* Origin: Marsh BBS (c) Dawson Creek BC Canada (1:17/23)