sch@linus.UUCP (Stephen C. Hemminger) (07/27/83)
MDM711
(NOTES ON HOW TO USE)
Copyright 1983
by
Irvin M. Hoff W6FFC
1 July 1983
NOTE: MDM710 NOW SUPPORTS AUTO-DIALING AND AUTOMATIC CONTINUOUS
REDIALING FOR THE FOLLOWING MODEMS:
PMMI 103 S-100 PLUG-IN MODEM
HAYES SMARTMODEM 300 OR 1200 MODEMS
U. S. ROBOTICS 300/1200 MODEM
(IT CAN STILL BE EASILY USED WITH OTHER EXTERNAL MODEMS
WITH MANUAL DIALING SUCH AS THE BELL 212A, RACAL-VADIC, ETC.)
INTRODUCTION:
------------
MDM711 enables a computer to communicate with another computer.
This is normally done by using standard telephone lines but with special
audio tones sending serial data. Two common speeds are used, depending
on the facilities available -- 300 Baud or 1200 Baud. A "modem" is used
which provides these audio tones. This is an acronym for "modulator and
demodulator". The one section (modulator) provides the audio tones for
sending over the telephone line and the other section (demodulator) then
converts those audio tones back to digital pulses the computer uses to
receive the incoming data.
The modem itself is a hardware utility, usually costing around $100
to $250 for a typical 300 Baud device and from $550 to $800 for a system
offering 1200 Baud as well as 300 Baud. Some of these (such as the PMMI
S-100 modem board) plug directly into the computer itself, while others
are totally independent of the computer and use an interconnect cable
(usually a RS-232 type) to control the external modem. A Bell 212A is
an excellent example of this type modem. Other examples would include
the Racal-Vadic, Hayes Smartmodem, U. S. Robotics, etc.
The program discussed in this guide allows each computer involved
to directly control its own modem, converting DC pulses into audio tones
which are sent to (or received from) the telephone line. (The standard
1200 baud transmissions use "DFSK" (phase shift keying) instead of "AFSK"
(audio frequency shift keying).
For short distances, no modems are required as the computer can
provide the necessary digital voltages. This discussion is centered
around systems intended for use over distances ranging from several
miles to literally around the world.
FEATURES:
--------
A program to communicate with another computer can range from very
simple to very complex. MDM711 is one of the more complex such programs
available today. It started in 1977 as a relatively simple program. It
was called MODEM2 at that time. It was intended to be used primarily as
a means of exchanging programs with other people in other cities. Since
that time a number of other (very useful) features have been added, in
addition to improved methods of program transfer. A list of some of the
features offered by this particular program include:
1) Ability to talk with another computer via keyboard at each end.
(Called the "terminal mode".)
2) Ability to operate a remote mainframe computer such as TYM-SHAR,
or special data bank systems now commonplace. This includes
"bulletin board" systems for receiving, sending or just read-
ing messges or other types of information.
3) Ability to upload (send) or download (receive) programs from other
computers whether TYM-SHAR, data banks, remote hobby systems
or just another individual in another location.
4) Ability to copy incoming information on a printer. If the print-
er is too slow to copy the data directly, the extra characters
back into a large storage buffer until they can be printed.
5) Ability to copy incoming data into memory for automatic transfer
to a disk file.
6) Accomodates any computer clock speed up to 25.5 MHz. in 0.1 Mhz.
increments for uniform results. (The clock speed is actually
of modest interest, it is only used for setting timing loops.)
7) Advanced type of error detection (CRC or Cyclic Redundancy Check)
using automatically generated high-speed lookup tables.
8) Automatic disconnect from the telephone line when using "BYE", "X"
or CTL-D. Two other disconnect commands with the PMMI modem.
9) This particular program has additional features of special inter-
est to those using the PMMI 103 S-100 plug-in modem, the U. S.
Robotics 300/1200, or the Hayes Smartmodem 300 or 1200. Those
features basically include automatic dialing and redialing (if
requested) until the other computer finally answers.
a) Automatic selection of a particular phone number from
a library of names and numbers.
b) Entry of a hand-typed number. Although it might be as
simple to manually dial the number as hand-type it, it
can then be automatically redialed indefinitely.
USING THE PROGRAM THE FIRST TIME:
--------------------------------
For now, we shall assume the program is ready to use on your equip-
ment. (Normally the user must make some modest changes to the program
before it can be used. This includes changing the port numbers and some
other personal options. These will be covered later in the section that
describes how to adapt it to your equipment.)
When the program is brought up is shows this display (if using the
PMMI modem):
MDM711 - (type M for Menu)
Version for PMMI S-100 modem starting at port: C0H
B>>COMMAND: x
The cursor stops at point "x:" waiting for some sort of command.
Typing a "M" followed immediately by a RETURN, shows the first page of
a 4-page help guide. If you do not have a PMMI modem, you would have
seen this (or a customized heading for your particular equipment):
MDM711 - (type M for Menu)
Version for Non-Pmmi modem
B>> COMMAND:
In this case only a 3-page help guide is used, since the 4th page
is used to assist those with the PMMI modem. It tells them a little
about changing from originate to answer mode, how to change Baud rates,
how to disconnect, etc.
Several commands are similar to those already used for CP/M, such
as 'ERA', 'DIR' and the ability to change disk drives and user areas.
This adds tremendous flexibility while remaining in the modem command
mode. To change disk drives, just say:
B>>COMMAND: A: <RET>
and you are in the same user area on the A: drive. You can also
say:
A>>COMMAND: A: 12 <RET>
to change user areas. When finished (using this example), say:
A12>>COMMAND: CPM <RET>
and you will go back to CP/M with the original driver and user area.
OPTIONS:
-------
There are 6 primary options and 13 secondary options that may be
typed on the command line. In additon there are over 35 commands ranging
from single character to three characters that can be used (such as DIR,
ERA, LOG, etc.) Those are listed on the menu. (The exact number varies
depending on whether you have the PMMI modem, etc.)
Primary Options: E, L, M, R, S, T
E = Echo mode (special type of full duplex)
L = Local modem (no remote echo, half duplex)
M = Menu display showing features that are available
R = Receive a file from remote facility
S = Send a file to a remote facility
T = Terminal mode (full duplex, echo provived remotely)
Secondary Options: A, B, D, L, O, Q, R, S, T, V, X, 0, 1
A = Answer mode (used only by PMMI modems)
B = Batch mode -- allows automatic multiple file transfer
(This is normally only used from modem-to-modem as
no RCP/M system supports batch mode file transfers.)
D = Disconnect when done, stay in MDM711
L = Local mode when finished with a file transfer
O = Originate mode (used only by PMMI modems)
Q = Quiet mode, special purpose feature rarely used except if
operating through a "BYE" program.
R = Receive data shown on CRT during file transfer
S = Send data shown on CRT during file transfer
T = Terminal mode when finished with a file transfer
V = Visual inspection of an ASCII file being transferred. Not
often used as most ASCII files are now "squeezed" for
minimum transfer time and disk space.
X = Exit to CP/M when finished, disconnect from phone line
0 = Odd parity (PMMI modem)
1 = Even parity (PMMI modem)
Although you can get the following information from the help guide
in MDM711, showing it here will allow us to discuss the various features
in somewhat better detail.
NOTE: THIS PROGRAM HAS SUPPORTED THE PMMI 103 S-100 PLUG-IN MODEM SINCE
ITS INCEPTION. IT NOW SUPPORTS THE HAYES SMARTMODEM 300 AND 1200
AND THE US ROBOTICS 300/1200 MODEM AS WELL. IN THE FOLLOWING
COMMENTS AN ASTERISK (*) BEHIND THE WORD PMMI MEANS ALL THE COM-
MENT IS PERTINENT TO ALL THESE MODEMS. OTHERWISE IT WOULD BE A
LITTLE AWKWARD TO ATTEMPT TO MENTION THEM ALL EACH TIME.
(*) THUS INDICATES PMMI, HAYES SMARTMODEM OR US ROBOTICS ALL APPLY.
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THE HELP GUIDE, PAGE 1:
----------------------
Single Letter Commands
? - Display current settings
M - Display the menu
E - Terminal mode with echo
L - Terminal mode with local echo
T - Terminal mode
For copying text to disk use T (or E or L) FILENAME.TYP
Start or Stop toggles described on subsequent screen.
R - Receive CP/M file using Christensen Protocol
S - Send CP/M file using Christensen Protocol
COMMAND: R (or S) FILENAME.TYP
R and S can use the following subcommands:
B - Bulk transfer using wildcards (e.g., *.*)
D - Disconnect when done
Q - Quiet mode (no messages to console)
T - Return to terminal mode after transfer
V - View bytes transferred on console
X - When done, disconnect, go to CP/M
The single letter commands may also be used on the
command line when the program is initially executed.
Hit any KEY to CONTINUE
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DISCUSSION OF HELP GUIDE PAGE 1:
-------------------------------
There are basically three types of commands that may be used with
this program:
1) Single-letter commands shown on page one.
2) Three-letter commands shown on page 2, and
3) Control-<char.> commands shown on page 3.
Going down the list:
? - shows current parameters. As these are closely tied in with some
of the other options, we shall show a typical example later
in this discussion.
M - shows the menu a page at a time. You may abort after any page is
shown with a control-C.
E - terminal mode with echo. When talking with another terminal also
also using MDM711 (or a comparable program), one of you must
send an "echo-back" so you can both see what the other person
is typing. This is needed for full-duplex operation. Usually
the person originating the call will type "E" instead of "T".
However either may do this. If "both" use the echo mode, the
program usually starts typing a string of feedback characters
since both computers are re-sending the same character over
and over. You can stop this by just returning to command mode
(type control-E) and then retyping "T" rather than "E".
L - terminal mode with local echo. Shows what you are typing but does
not send an echo of the other person's typing back to him.
Can be used at both ends, in place of one person using "E".
Both "E" and "L" are useful at times for some types of modems
that do not use full-duplex, or for some main frame units that
run half-duplex. The combination of "T", "E" and "L" gives an
excellent choice to use on various systems. Normally the "T"
mode is sufficient except when talking with another person and
then the "E" mode at one end or "L" mode at both ends will
provide normal results.
T - if typed as the first (primary) option, puts the program directly
into "terminal mode", allowing it to send from the keyboard to
the other computer, and to copy anything coming from the other
computer with the exception of file transfers (use "R" to re-
ceive those).
R - used only for receiving files from the other computer. These are
usually sent in binary form with either checksum verification
or more commonly, CRC (Cyclic Redundancy Checking). If ready
to receive another file, you have several choices, depending
on the program used by the other computer. After notifying
him you are ready (or will be very shortly), you can type:
B>>COMMAND: R HELLO.DOC <RET>
and when he starts to send you will receive the program which
then goes directly to the disk when finished, or every 16K if
longer than 16K total. You could also have said:
B>>COMMAND: RT HELLO.DOC <RET>
and when the transfer was completed, it will automatically
return you to the terminal mode. This is useful when trans-
ferring programs to/from other systems, as it automatically
places you in a "ready to go again" situation when the trans-
fer is finished.
Another "R" option would be:
B>>COMMAND: RB <RET>
This is called the "Batch mode" and is an extremely useful way
to receive programs automatically, from another computer using
a similar program. He will use the batch mode for sending the
programs and that automatically provides the file names at the
receiving end. In this manner, large numbers of programs can
be transferred completely automatically, including full disks.
(Assuming you care to pay the toll calls for the time it will
take!)
NOTE: The ideal way to receive batch mode would be:
B>>COMMAND: RBT <RET>
since you may not know in advance how many programs he
will be sending. When the transfer is complete, you
are automatically in the "T" mode and he can start
typing to you, immediately, with any comments relative
to the progress of the transfer, etc. (He would use
the "E" mode.)
S - Send programs. Similar to "R" but sends instead of receives. If
the other system is ready to receive, you can type:
B>>COMMAND: S HELLO.DOC <RET>
It will tell you how many records are involved and how many
minutes and seconds it will take to send the program. If the
other system is ready to receive, it starts the transfer,
showing how many records have been sent. If any errors occur
during transmission, it shows what they are and counts them.
It will resend any records not correctly received at the other
computer. If too many consecutive errors occur (normally set
at 10), the transfer is terminated. The batch mode may also
be used for sending:
B>>COMMAND: SB HELLO.*
will send all files starting with HELLO, or can send just one
file, or can send several non-related files in this manner:
B>>COMMAND: SB HELLO.DOC XDIR.COM TERM.*
etc. Be sure to put a space between the various files. You
can include the 'X' option:
B>>COMMAND: SBX HELLO.* MDM711.LBR MDM711.AQM
When the file transfer is completed it disconnects from the
phone line and reverts to CP/M. This allows you to be absent
when the file is finished, offering an advantage when sending
lengthy files.
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THE HELP GUIDE, PAGE 2:
----------------------
Three Letter Commands
CPM - Exit from this program to CP/M
DIR - List directory and space free (may specify drive)
ERA - Erase file (may specify drive)
LOG - Change default drive/user no. (specify drive/user)
and reset disks. e.g. LOG A0: or LOG B: (user # unchanged)
SPD - Set speed of file output in terminal mode
TIM - Select Baud rate for "time-to-send" message
TCC - Toggle CRC/Checksum mode on receive
TBR - Toggle backspace to rubout conversion
TLC - Toggle 1) local command immediate
2) local command after CTL-^
TLF - Toggle LF after CR when sending disk file in "T" mode
TXO - Toggle XOFF testing in terminal mode file output
NUM - List remote systems
SET - Set modem baud rate
BYE - Disconnect, then return to CP/M
CAL - Dial number
DSC - Disconnect from the phone line
The following are terminal text buffer commands:
DEL - Delete memory buffer and file
WRT - Write memory buffer to disk file
Hit any KEY to CONTINUE
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DISCUSSION OF HELP GUIDE, PAGE 2:
--------------------------------
CPM - This returns to normal CP/M use, abandoning MDM711.
CAUTION: It does not disconnect the modem from the phone line.
DIR - Enables the user to see the library of any disk without needing
to return to CP/M first. Can be adjusted when installing the
program to show 3, 4, or 5 groups depending on the width of
your CRT display. Normally set to 5 for 80-column displays.
Shows the amount of disk spacing remaining on the logged-in
default drive. (You must log in any drive you wish to write
on, or to see the correct free disk space remaining.) See the
LOG feature below.
ERA - Enables the user to erase any files from any disk without the
need to return to CP/M first. Wild cards (* and ?) accepted.
LOG - When a new disk is inserted, you can see the directory and read
files from it but cannot write to it without getting a "BDOS
ERR". This command allows you to log in a new disk so you can
immediately write on it without first returning to CP/M for a
warm boot. You can select drive and user number. (This also
enables DIR to show the correct free disk space remaining.)
You can say:
LOG <RET> for same drive, user area, new disk
LOG A
LOG A:
LOG A14 (user areas are 0-15)
LOG A11:
SPD - Sets the delay between characters and/or delay between lines in
the "T" mode when using control-T to upload a pre-typed file.
Since most bulletin boards and TYM-SHAR systems normally use
line editors that require a delay after they have received a
line, you can add delay between characters (in increments of
10 ms.) and/or enter delay between lines (in increments of 100
ms.). This is preset for most systems at 50 and 500 ms. They
can be changed at any time. Current values can be checked by
using the " ? " command.
TIM - This option lets you set the file transfer time from 110 Baud to
9600 Baud. You can preset it (when installing the program) to
the value normally used, but at times it is nice to be able to
conveniently change the time shown to a different rate. Some
initialization routines (discussed in the install section) can
make this change automatically. This command does not show if
using the PMMI* board as the speed is automatically changed to
agree with the current Baud rate selection. It also does not
show if the custom overlay uses the SET command to choose var-
ious Baud rates as the transfer time is changed automatically.
TCC - Most modem programs originally used simple checksum verification
of received sectors. Most now use Cyclic Redundancy Checking
which finds certain transmission errors the simple checksum
system might overlook. This toggle allows the user to select
checksum for those systems known to not offer CRC. When set
normally to CRC, the program automatically switches to check-
sum after trying several times to use CRC.
TBR - Some systems use the "rubout" key for backspace. This toggle
allows you to readily adapt to those systems. Rarely used.
TLC - Nearly all computers use "control-characters" to do various
tasks such as move the cursor around, clear the screen, reboot
the system, etc. You might want to send a control-E character
to the local computer and not have it go to the remote system
at the same time. Say a moment later you would like to send a
control-E only to the remote computer. You would do this:
control-E (goes to local computer only)
control-^ control-E (goes to the remote computer only)
You can reverse the TLC toggle causing this response:
control-E (goes to remote computer only)
control-^ control-E (goes to the local computer only)
All other control-chars. would operate in a similar manner.
This gives extra flexibility in using this program for special
systems like TYM-SHAR, etc.
NOTE: If using control-^ is awkward, you can pick a different
character when installing the program initially.
TLF - If sending a file while in terminal mode (via CTL-T option) most
mainframe computers will not want you to send a line feed. As
all editors include the LF after CR, you have the option with
this toggle of sending or not sending a line feed. If typing
manually in the "T" mode, you can get a line feed with CTL-J.
It is automatically included after CR with "L" or "E" modes.
TXO - Used when uploading pre-typed text files to other systems such
as TYM-SHAR or bulletin boards, etc. Most of those have line
editors that take a moment to move the line you just finished
from their edit buffer into memory. The XOFF character halts
your system from sending until it is ready for a new line.
Used only in the terminal mode.
NUM - Not shown if using PMMI*. This shows the non-PMMI* people the
phone library numbers which can be used for manual dialing.
SET - Not shown if using PMMI, or if SETUPR is set to "NO" (indicating
no user routine in the overlay for choosing different speeds.)
BYE - Disconnects the modem from the phone line, closes any file that
may be open and returns to CP/M.
CAL - PMMI* command, shows the phone library for auto-dialing. If not
using a PMMI*, this and the following two commands will not be
shown, instead NUM is shown. If typed, the telephone library
is displayed. This is useful even for non-PMMI users, as will
store useful phone numbers for manual dialing.
DSC - Dsconnects the modem from the phone line whenever selected.
DEL - If copying incoming information into memory, and you decide you
do not want to bother saving it to disk after all, this closes
(and then deletes) the disk file you had opened.
WRT - saves what you have been copying to the disk file already opened
for that purpose. When returning from the "T" mode to command
mode, a warning is shown that you may lose what has been saved
unless you use WRT (write to disk).
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THE HELP GUIDE, PAGE 3:
----------------------
Local Commands while in Terminal Mode
CTL-@ - Send a break tone for 300 ms.
CTL-B - Change Baud rate
CTL-E - Exit to command mode
CTL-N - Disconnect from the phone line
CTL-O - Send log-on message
CTL-P - Toggle printer
CTL-Y - Start copy into buffer
CTL-R - Stop copy into buffer
Start & Stop may be toggled as often as desired.
A ":" at start of line indicates buffer is copying.
XOFF automatically used to stop input when writing
full buffer to disk, XON sent to resume.
CTL-T - Transfer ASCII file to remote
CTL-^ - Send local control character to remote
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DISCUSSION OF HELP GUIDE, PAGE 3:
--------------------------------
CTL-@ - Sends a break character to the other computer. Used in some
TYM-SHAR systems, etc. (Used only in PMMI mode)
CTL-B - PMMI command, changes the Baud rate from 110-711, in addition
changes the file transfer time accordingly.
CTL-E - Returns to command modem from "T", "L", "E" modes.
CTL-N - Disconnect the modem from the phone line.
CTL-O - Will send the log-on message if TRANLOGON is set YES and a
message has been including in the LOGON area. Can use this
feature to sign on various bulletin board systems, although
that would require an identical password on each.
CTL-P - Toggles the printer on-off. Very useful feature. Similar to
normal control-P but in this case if the modem is running
faster than normal printer speed, the characters just back
into a special buffer while the printer tries to catch up.
Most dot matrix printers are considerably faster than most
telephone modems, however. Can be toggled at any time you
are in the "T", "L" or "E" modes. Often used to copy items
from bulletin boards, etc. that are not worth permanently
saving on disk.
CTL-Y - Used only in terminal mode. If a file was opened prior to
going to "T" (terminal) mode, nothing will be saved until
control-Y is typed. This places a ";" (semicolon) at the
start of each new line, indicating the memory is "hot" and
is now copying for saving to a file. You can toggle this
off by using control-R.
CTL-R - Stops the copy into memory, shuts off the ";" at start of
each line. These two commands (CTL-Y to start, and CTL-R
to stop) control what is being saved. When returning to
command (via CTL-E), you will then be warned to save the
information to disk via the WRT command or it will likely
be lost.
(These commands -- CTL-P, CTL-Y and CTL-R give
MDM711 tremendous versatility. You can copy
incoming data either to disk or to printer (or
both). My own printer is a 300 Baud Teletype
Corporation Model 43, yet it works great when I
am using the Bell 212A at 1200 Baud. The printer
falls behind, but misses nothing as it eventually
catches up with the contents of the large buffer.)
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THE HELP GUIDE, SPECIAL PMMI PAGE:
---------------------------------
Additional Subcommands for PMMI Modems
Modem control:
A - Answer tone for send or receive
O - Originate tone for send or receive
Parity options:
1 - Set and check for odd parity
0 - Set and check for even parity
Both ends must be capable of these options
which are available only in R and S modes.
The parity checking will be part of the
file transfer protocol.
Speed Options:
After entering your primary and secondary options,
you can set the modem speed by placing a "." after
the options followed by the speed e.g., 300, 1200.
EXAMPLE: SBOT.600 will set the modem for 600 baud
Hit any KEY to CONTINUE
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DISCUSSION OF HELP GUIDE, SPECIAL PMMI PAGE:
-------------------------------------------
When using MDM711 with the PMMI board, you will either dial out or
(far less likely) answer some incoming call. Since the unit will be in
"originate mode" about 98% of the time, it is set to automatically come
up in the originate mode at default speed (300 Baud) whenever a call has
been completed. If you want to use answer mode, you need to use the "A"
command. If a speed is not included, it will stay at the default speed.
Until a connection has been made, there are no tones applied to the
line. Originate tones at 300 Baud are automatically added at that time.
In addition to telling the PMMI modem if it should use originate or
answer tones, you can tell it what Baud rate to use. A typical command
(once connection is made to another modem) would be:
B>>COMMAND: TO.600 <RET>
This puts the tones on the phone line for originate and at the
same time sets the PMMI board for 600 Baud. Another typical response
might be:
B>>COMMAND: RABT.450 <RET>
This places the answer tones on the phone line, sets the program
for receiving batch mode at 450 Baud and returns to terminal mode when
the transfer is completed.
Other optional PMMI commands seem self-explanatory, such as dis-
connect, etc.
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PMMI, HAYES AND ROBOTICS AUTO-DIALING AND AUTO-REDIALING:
--------------------------------------------------------
There are several very useful and versatile features offered for
the PMMI, Hayes Smartmodem and Robotics users.
There are several ways to auto-dial.
1) from the command line
2) from the phone number library line
In addition you can auto-redial from either of these lines. Once
the number has auto-dialed and there is no answer, it will ask you if
you want it to continuously auto-redial until it does receive an answer
(or you decide to abort).
To get the phone library, type CAT <ret> on the command line. You
then normally just type the alphabetic character at the start of the ap-
propriate line. It will then show the number being dialed. You can also
do this from the main command line if you know in advance what alphabetic
character is associated with that particular number:
B>>COMMAND: CAL P <RET>
This calls up the "P" line in the library and dials that number,
then if busy asks if you want it to continue redialing. You can use:
B>>COMMAND: CAL 313-749-6569 <RET>
and it will dial the number specified. You can then do either of
these on the library command line, as well. This gives a tremendous
versatility.
NOTE: PMMI is planning to offer a new S-100 modem board approximately
July. This will add 1200 Baud to the PMMI system, something it
has sorely lacked. At that time the PMMI modem will be able to
communicate with Bell 212A type modems at 1200 Baud in addition
to the slower 300 Baud modems. This will cut long distance tele-
phone bills for transferring files to/from remote CP/M to about
25% normal charges, plus reduce the operator's time by the same
amount. This new board is not expected to support 600 Baud.
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CASCADING COMMANDS:
------------------
Several commands may be used on the same line. Ones normally used
are: A, B, D, E, L, O, Q, R, S, T, V, X (and Baud rate if PMMI).
A typical PMMI selection might be: RABQ.300
The commands have been listed previously but will be listed here
again:
A) answer tones for PMMI S-100 modem, puts tones online.
B) batch mode (must be used at both ends if used at all)
(usually only available modem-to-modem with operators
present at each end.)
E) echo mode for conversing with a system not offering echo.
L) local echo shows what you are sending if no remote echo.
O) originate tones for PMMI S-100 modem, puts tones online.
Q) quiet mode, suppresses messages on local console.
R) receive file transfers with CRC or checksum protocol.
S) send file transfers, also shows transfer time.
T) terminal mode - operates computer at other end like a remote
terminal. Also stands for "text mode". When in "T" mode
you can copy incoming to printer or to disk, and send pre-
typed ASCII text files via CTL-T.
V) visual -- lets you see incoming ASCII files while being sent
to the disk system.
NOTE: The Baud rate is only used for the PMMI S-100 modem.
Many of the custom overlays allow use of the SET
command to change Baud rate with non-PMMI modems.
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TYPICAL PARAMETERS SHOWN BY THE "?" COMMAND:
-------------------------------------------
B> COMMAND (H for Help): ? <RET>
Mode: CRC
Printer is OFF
Backspace is backspace
Modem speed is 300 baud
Termianl mode file buffer is inactive
Unused portion of buffer is 16384 bytes
Use CTL-^ to send local command to remote
Linefeed NOT sent after CR for disk file in T-mode
XOFF testing NOT used in terminal mode file output
XON NOT automatically tested after CR in terminal mode file output
Char. delay (terminal file mode) is: 50 ms. per character
Line delay (terminal file mode) is: 500 ms. per character
- - - - - - - - - - - - - - - - - -
DISCUSSION OF TYPICAL PARMETERS SHOWN BY THE "?" COMMAND:
--------------------------------------------------------
By this time, most of these parameters are self-explanatory. They
primarily show how the options and toggles have been set. The user can
check on any of the major parameters at any time by:
1) Typing control-E to return to command mode and
2) Typing ? to see the list of current parameters.
- - - - - - - - - - - - - - - - - -
INSTALLING THE PROGRAM:
----------------------
Although this is obviously the very first thing that needs to be
done, it was saved until last for several reasons. The most important
of these was the need to first explain what some of the options will do
when selected.
By this time the user should have a fairly good idea what options
would work best for him. When looking at the beginning of the program
where the these are selected, it should now be rather easy to pick the
ones that are most useful.
There are various ways to change the program to suit a specific
user. These are discussed to a modest extent in the information file
called MDM711.INF. Essentially you are given several methods. You can
edit MDM711.ASM with your selections, then assemble it. Or you can use
DDT together with MDM711.COM and one of the overlay programs that was
made for your computer system. This is essentially the complete front
end of MDM711.ASM. Changing those equates, etc. is similar to editing
and assembling the main program. It will likely be far easier since the
overlays are already designed for that particular equipment. In most
case no changes at all will be needed.
Thus various methods are available, one of which should provide the
easiest method for your system.
NOTE: Although designed with special emphasis on the auto-dialing and
redialing capability of the PMMI, Hayes Smartmodem or Robotics,
it works quite well on non-PMMI modems. In the author's system
a stock Bell 212A Dataphone is used together with a normal ser-
ial I/O that can easily switch from 300 to 1200 Baud. The system
includes a Teletype Corp. Model 43 dot matrix 300 Baud printer.
A great variety of other computers and modems can use this same
program quite easily. This is likely the most versatile phone
modem program currently available for CP/M users.
OUR THANKS TO:
-------------
A great number of people have contributed to the growth of this
program since 1977. Two people have been particularly helpful to me in
developing the MDM700 series modem programs: Keith Petersen (W8SDZ)
and Frank Gaude' (ex-K6IBE). Their help and interest have been greatly
appreciated.
We hope this verstile program will give you hours of enjoyment and
fulfill your modem needs. It has long been a goal of mine to provide
the same program for the people using the Hayes Smartmodem (or Robotics)
as for those using the PMMI modem.
- Irv Hoff W6FFC
--
Stephen Hemminger, Mitre Corp. Bedford MA
{allegra,genrad,ihnp4, utzoo}!linus!sch (UUCP)
linus!sch@mitre-bedford (ARPA)