through IBM user groups. If they’re ethical, they’ll encourage you to
send a small “donation” to PC-Talk’s originator, Andrew Fluegelman, who
wanted to save distribution expenses through this “freeware” approach.
You needn’t feel obligated to pay until you’ve tried the program.
Probably, however, you’ll find PC-TALK to be worth the $35 or $45 it may
cost; this software is more sophisticated than MODEM7, which I’m
focusing on because of its simplicity.
Another excellent MODEM7 alternative—_for experienced computer-users_—is
MEX. CP/M versions are available free through users groups and work on
many machines, including Kaypros; and NightOwl Software (telephone
800/648-3695 or NITEOWL) expects to sell it for $59.95 in an IBM
version. Most of MEX’s send-and-receive commands overlap with MODEM7’s.
MODEM7 as of 12/18/80
Originally Written by Ward Christensen
Revisions by Mark M. Zeiger, Jim Mills
WRT —Write file to disk (from terminal mode)
DEL —Erase present file (from terminal mode)
RET —Return to terminal mode with no loss of data
XPR —Toggle expert mode (Menu on/off)
DIR —List directory (may specify drive)
CPM —Exit to CP/M
S —Send CP/M file
R —Receive CP/M file
T —Terminal mode (optional file name)
E —Terminal mode with echo
DEFAULT DRIVE:
Command:
IBM PC owners, fear not! This Kaypro version of MODEM7 shows the same
menu that the IBM version, dated Oct. 15, 1982, does. The only real
difference is the IBM adaptation’s use of the =DOS= command instead of
the =CPM= one to return to the computer’s operating system.
Here now is a plain-English guide to MODEM7’s version of December 18,
1980, as adapted in 1982 for the Kaypro, IBM, and many other machines.
TO GET READY
MODEM7 has two basic modes for Teletype-like communications, “Terminal”
and “Echo.” For both parties to see both ends of the conversation, one
must be in “terminal” and the other in “echo” if they are communicating
directly. Just the “terminal” person will be able to record on his or
her disk. The one in echo mode can’t save the material electronically.
Beginning, you should read your computer’s instructions for information
on how many stop bits and data bits your machine normally runs with. And
does it use odd, even, or no parity? You might also get this information
from your dealer or users group.
Don’t worry right now about knowing about the full meanings of the
terms. Just find out what the settings are.
MODEM7 doesn’t provide for changing the settings. If the person at the
other end can’t adjust them, either, and if those for his machine are
different from yours, you’re out of luck if you don’t know how to fix
the program code. You two may have to reach each other through an
electronic mail service that mediates between machines. Often, however,
micros are set for 1 stop bit, 8 data bits, and no parity, an informal
standard. And just about all decent commercial programs for
communications let you alter these settings. So does PC-TALK III.
In addition, even though MODEM7 itself won’t change its bit settings,
your user group may have some free or low-cost programs that you can
load up to do the trick—and then use MODEM7.
There’s one other little worry. Are you and the other person sending at
the same speed over the phone lines? The normal speed for cheap micro
modems is 300 baud or about 30 characters per second; for the deluxe
ones, 1,200 baud. Don’t worry right now about what a baud is. Just make
sure you and the other person are both at the same speed. MODEM7 often
is set at 300. Some versions may allow for changing the software to
accommodate different baud rates, but the command may not work on your
particular brand of machine. By the way, remember that you must consider
the baud rate not only of the software but of the hardware. Simply
adjusting your software to send at 1,200 baud won’t do the trick if your
modem can reach only 300 baud. Remember, too, that MODEM7’s speed
command won’t necessarily govern your modem’s transmission speed, just
your software’s.
You also want to find out how to operate your modem. Some use a physical
switch to change from voice to data. Others—smart modems—use commands
that you type out while your modem program is in the terminal mode. You
can tell a smart modem to dial a number or answer the phone
automatically.
TO TRANSMIT AND RECEIVE WITHOUT SAVING ANYTHING ON YOUR DISK
Just think of your computer and the other person’s as two Teletype
machines connected. When hitting a key on either Teletype, you or the
other person can make the two both print, right? Well, it’s the same
with the computers. Here, however, the “print” is characters on your two
screens.
Ready?
1. Start out with the other person’s modem set on ORIGINATE and yours on
ANSWER (or vice versa) if the modems lack automatic switching.
2. Type =MODEM7= after the A> prompt of CP/M (or PC-DOS).
3. Hit your carriage-return key.
The menu listing your choices will flash onto your screen.
4. Hit the letter =T=.
5. Tap the return.
6. Assuming you’re using a manual modem, flick the switch to “data.”
With a smart modem, you use the right keystrokes to awaken the gizmo
or get it to answer the other computer.
Most smart modems nowadays employ commands similar to those of the Hayes
models. With Hayes-style modems, if two people are switching from voice
to data, one will type =ATD= and a carriage return (to start getting the
modems talking), and the other will type =ATA= (to answer
electronically).
If you’re talking to another micro or a little terminal hooked up to the
phone at the other end, you may need to type =E= (and the return)
instead of =T= (and the return).
That’s the echo mode, which you’ll recall differs from the “terminal”
one. =E= lets you see your own typing. Again, normally, one micro user
will be in echo, and one will use the straight terminal mode. When
communicating with a bulletin board, even on a micro, use the =T=
command rather than =E=.
How to switch from the regular terminal mode to the echo mode or the
reverse?
You use MODEM7’s electronic gear shift. That’s =Control-E=; don’t
confuse it with the =E= used in the echo mode. You tap out this command
in other situations, too, whenever you want to return to MODEM7’s main
menu. A =Control-E=, of course, consists of holding one finger on the
=CNTRL= or control button and then hitting the letter =E=.
Here’s a warning: you may need to hit the line feed and/or the carriage
return at the end of each line for your words to come out in the right
places on the other person’s screen.
The terminal mode is worth using even when you and the other person only
plan to exchange electronic files. If the terminal mode doesn’t work,
then the others probably won’t, so use the terminal mode first to pave
the way for file exchanges. By the way, the terminal mode is just the
ticket to communicate with information utilities like The Source or with
bulletin boards.
TO RETURN TO THE OPERATING SYSTEM OF YOUR COMPUTER
To return to CP/M—to crank up WordStar or Perfect Writer, for
instance—you:
1. Type =Control-E=.
2. Tap out =CPM= from the main menu.
3. Hit your return.
Bingo! You’re back with the A>! And from there you go on to WordStar,
etc.
If you’re using the IBM version of MODEM7, you use the command =DOS=
instead of =CPM= (unless your menu says otherwise).
TO TRANSMIT MATERIAL ON YOUR DISK WITHOUT ERROR CHECKING—WITHOUT A
MODEM7-STYLE PROGRAM AT THE OTHER END
MODEM7 uses the Ward Christensen Protocol—sometimes called the XMODEM
Protocol—to help make sure the material is going from computer to
computer okay.
If you don’t use error checking in transmitting files, the static on the
phone lines may garble some words. Your computer, after all, is just
squirting your file over the phone without bothering to find out if the
other machine is receiving it right. You want error checking if you’re
transmitting or receiving software; just one electronic goof, just a
single messed-up “one” or “zero,” can throw the whole program out of
whack.
But sometimes, when you aren’t dealing with programs, you’ll want to
skip error checking. That way, the transmission will go faster. And
it’ll be easier for computers with different communications programs to
talk to one another.
There’s still no guarantee you’ll communicate, but with an industry
standard like MODEM7 you have a good shot at it.
Here, then, is what you do to send a file to someone without a
MODEM7-style program:
1. From MODEM7’s main menu, you select =T= and again hit the return a
few times.
2. Find out if the other person can read words you type. (Don’t worry if
you yourself can’t read your own words.)
3. Tell him (or her) to set up his computer so that, on paper or on a
disk, it’ll record what it receives.
4. Once the other person is ready—while you’re still in the =T= mode—hit
=T= again, but this second time your finger is on the Control key
while you’re doing so.
The screen will ask you the name of the file you want sent. Normally,
that file will be on your data disk, the one on drive B. B in that
case contains the articles, reports, etc., for which you may lack room
on the A disk containing your programs. (But if the document to be
sent is on A, substitute that letter for =B= in the rest of the
steps.)
5. Now you type =B:[name of file]=. Here and elsewhere don’t type the
brackets surrounding the file name—and please put the file name
directly after =B:= without a space in between.
6. Next hit your return. The disk should start spinning, and both you
and the person at the other end should see your file flashing across
the screens. Following transmission, your computer will say FILE
TRANSFER COMPLETED. The other person should now have an electronic
copy on his own disk.
TO RECEIVE COPY WITHOUT A MODEM7-STYLE ERROR CHECKING
1. Get the two modems talking, then return to the main menu.
2. Again, select your trusty =T= from the main menu. But don’t hit your
return immediately.
3. Type a space.
4. Type =B:[the name of the file you’re creating on the data disk to
receive the other person’s file]=. The name on B can be anything you
want except a file that’s already on the disk.
In other words, if you want to save the other person’s file under the
name MAGIC, you type: =T B:MAGIC=.
5. Hit your return once or twice.
6. Then hit the letter =Y= with your finger on the control key
(=Control-Y=).
You’ll see some colons on the screen when material starts flashing
across it. They won’t show up, though, in the file you’re creating.
They’re merely an indication that the computer is saving
material—whether it’s a file, an item from a computer network, or
someone just typing away.
7. Type =Control-E= to return to MODEM7’s main menu.
8. Then, to preserve the file, “writing” to your disk, you must type out
=WRT=, then hit your return.
And that’s it. You’re done!
By the way, if, while receiving material, you decide there’s a part you
don’t need saved, you can leave that out of the file you’re creating.
Just hit =Control-Y= again. Hit it still another time if you want to
return to the “save” mode. On some successors to MODEM7 such as MDM711,
a =Control-R= rather than a second =Control-Y= will tell the computer to
shut off the save feature.
This save feature, alas, won’t work on a computer using the older
MODEM7’s echo mode (though it will with newer versions of the program).
But you can get around the shortcoming. Ask the other person in advance
to make a two-way record of your conversation and send it to you! How to
receive it? Well, after you’ve transmitted in the =E= or echo mode, you
can shift to =T= with a file name added to save material.
Please also remember that MODEM7’s capture buffer—the feature letting it
save incoming material to your disk—is small. Often the buffer can’t
work safely with files bigger than 16K. That’s about eight double-spaced
pages. If you’re using a Ward Christensen Protocol, however, files can
normally be as long as disk space allows.
Printing the saved material, you may experience some problems because
different word processors aren’t absolutely compatible with each other.
You may see odd format commands, for instance, like “@”s (noticeable to
WordStar buffs reading the files of their not-so-Perfect Writer friends)
or “.HE” (a WordStar command that may baffle the Perfect crowd). But
once you get the hang of it, you can usually “clean up” such “garbage.”
TO TRANSMIT COPY TO SOMEONE WITH A MODEM7-STYLE PROGRAM
1. Get the modems to start jabbering to each other.
2. From MODEM7’s main menu, type =S B:[name of the data disk file you
want to transmit—either a program or a letter= =or other document]=.
The =B:= shows the file is on the =B= disk. If it isn’t, just type =S=
and the name of the file—for instance, =S MAGIC=. If =MAGIC= is on
=B=, type =S B:MAGIC=.
3. Hit the return.
Soon your computer should start constantly asking the other machine if
it’s getting your file okay.
If it isn’t?
Then your computer will conscientiously try again. But its patience is
limited. It’ll give up eventually if the two machines and their software
aren’t on speaking terms.
And if everything does work? Your computer will beep when it’s through
or at least flash a message letting you know that it’s done.
_Note_: If the other person is using some versions of MODEM7, you may
have to ask him to switch on the “check sum” form of error checking.
This guide is for the simple old MODEM7, not newer versions. Most of the
commands, however, will also work with the updated varieties, and of
course all versions of MODEM7 can communicate with each other, subject
to minor adjustments. _Some_ versions use the =TCC= command to turn on
the check-sum mode.
TO RECEIVE FROM SOMEONE WITH A MODEM7-STYLE PROGRAM
1. Fire up your modem.
2. Type =R B:[new file name]=.
3. Hit your return.
Your computer will tell you when it’s through receiving. Remember, the
material will show up on your data disk. If you want the material on the
other disk, just type =R A:[file name]= instead.
TO FIND OUT IN A HURRY IF YOUR COMPUTER SAVED A FILE SENT BY MODEM
(ASSUMING YOU’RE USING AN OPERATING SYSTEM LIKE CP/M OR PC-DOS)
1. Go to the =A=> prompt.
2. Type the word TYPE, then a space, then the name of the file—preceded
by a =B:=, of course, if it’s on the data disk.
Immediately after the A> you should have the equivalent of =TYPE
B:MAGIC=.
3. Then hit your return.
This is a CP/M and PC-DOS procedure.
TO ERASE A FILE (FROM CP/M)
Do the above, except substitute =ERA= for =TYPE=. Say you want to erase
=MAGIC=. Just type =ERA B:MAGIC=.
TO ERASE A FILE (IF YOU’RE USING PC-DOS)
Use =DEL= instead of =ERA=. Type =DEL B:MAGIC=.
TO ERASE A FILE FROM WITHIN THE MODEM7 PROGRAM
Type =DEL B:MAGIC= or whatever the file name is.
TO FIND OUT WHAT’S ON YOUR DISKS WHILE YOU’RE USING MODEM7
1. Type =DIR= from the main MODEM7 menu.
2. Type a space.
3. Type =B:=.
4. Hit your return.
This will show the contents of the =B= drive, normally used for storing
data.
To see =A= drive’s contents, you merely type =DIR= and hit the return.
TO USE THE DIRECTORY FEATURE WHILE YOU’RE IN THE MIDDLE OF A FILE YOU
USE TO SAVE
What if you want to save the other person’s message using the =T
B:MAGIC= method—but in the middle of the conversation you also want to
check the contents of your disk via the =DIR= command?
How do you prevent the =MAGIC= from disappearing except for the name on
your file list?
After all, an electronic file is like gas inside a bottle. You must
“cap” it with a =WRT= command, or the gas will leak out the top. And you
can’t reenter your file by typing another =T B:MAGIC=.
But you _can_ get back to =T B:MAGIC= by typing =RET= after the =DIR=
command.
TO GET THE MENU OFF THE SCREEN ONCE YOU KNOW THE ROPES
From the main menu, type =XPR=. Hit the return.
TO CHANGE THE BAUD RATE
If you’re using MODEM7 with a 300-baud modem, you don’t worry; the
software normally comes set for that speed.
With a 1,200-baud modem, you may be able to accommodate the higher speed
this way:
1. Enter the =T= mode of MODEM7 from the main menu.
2. Hit the return several times.
3. Tap =Control-B=.
You’ll then see a request for a new baud rate.
4. Type the right number (300 for 300 baud, 1200 for 1,200; do not use
commas—MODEM7 doesn’t like them here).
5. Hit your return.
Please note that at least on my Kaypro II the =Control-B= command
doesn’t work. This may have been due simply to my machine’s quirks.
Again, don’t forget that MODEM7’s successors operate somewhat
differently and may use a command such as =SET= or =TIM= to set up the
baud selection.
And remember, too, that the old MODEM7’s baud command won’t control the
speed of your modem (although some modems will automatically pick up the
baud rate of the one at the other end).
Thanks to Jon Albers, Eric Meyer, Rick Nelson, and Pat Ehresmann for
checking the accuracy and clarity of the above instructions. Blame me,
however, if anything’s wrong.
My instructions are a simplification of:
=CP/M MODEM PROGRAM DOCUMENTATION by Mark M. Zeiger
and James K. Mills 11/04/80=
The MODEM7-styles programs have their origins in the work of Ward
Christensen, an IBM employee and public-spirited computer hobbyist.
■ ■ ■
A MODEM7 Cheat Sheet
Snip this out! It’s a handy summary of commands for the free MODEM7
program.
◾ _TO MAKE MODEM7 APPEAR ON YOUR COMPUTER SCREEN_: Type MODEM7 from
the A> prompt and hit your carriage return. You’ll end up in the
program’s main menu. Or if you’re using a new program, you might
instead see a screen telling how to reach the menu.
◾ _TO USE THE TELETYPE-LIKE TERMINAL MODE_: Tap the letter =T= and a
carriage return after the main menu appears. You can use this mode
with The Source, MCI Mail, and other on-line services.
◾ _TO USE THE ECHO MODE_: Type =E= and the return. For Teletype-like
use when the other machine is in “Terminal.”
◾ _TO GO FROM ONE MODE TO ANOTHER_: Use =Control-E=. This gearshift
mode returns you to the main menu.
◾ _TO SEND MATERIAL ON YOUR DISK WITHOUT THE WARD CHRISTENSEN
ERROR-CHECKING PROTOCOL_: Type =Control-T= after you’re in the
terminal mode. Give the name of the file to transmit. Here, as in
other cases, precede the name by =B:= (no space after the :) if
the file is on Drive B. Hit your carriage return.
◾ _TO RECEIVE MATERIAL WITHOUT A PROTOCOL_: After typing the usual
=T= in the terminal mode, you skip a space. Then specify the name
of the file where you’ll collect the received data. Now hit your
return several times. Use =Control-Y= to tell your computer to
start saving material; also use it to turn off the save feature.
(On newer versions of MODEM7, =Control-R= might be the off
switch.) _IMPORTANT_: After you’ve finished talking to the other
machine, you must return to the main menu and type =WRT= and
return. Otherwise your computer won’t save the material on the
disk.
◾ _TO SEND TO SOMEONE WITH A MODEM7-STYLE PROTOCOL_: Type =S=, skip
a space, then type the name of the file that you’ll send—with the
=B:= before it if necessary. Hit the carriage return.
◾ _TO RECEIVE FROM SOMEONE WITH A MODEM7-STYLE PROTOCOL_: Type =R=.
Skip a space. Then type the name of the file where the material
will show up, using =B:= if needed. Hit the return.
◾ _TO RETURN TO THE A> PROMPT_: From MODEM7’s main menu, type =CPM=
if you’re using a CP/M version like the Kaypro one. (The IBM
version substitutes =DOS= for =CPM=.) Hit your return.
■ ■ ■
BACKUP XIII ❑ Why Not an Electronic Peace Corps?
In a Chicago suburb a $50,000-a-year engineer spends countless hours
twiddling with his new IBM PC. The technology engrosses him, but he
lacks a sense of purpose. In Southeast Asia, meanwhile, a young man
wrestles with calculations needed to build an irrigation dam. He thinks
his figures are correct but isn’t certain, and thousands of people will
die if the dam collapses.
Can the Chicago engineer somehow help his counterpart abroad?
There is a way if politicians for once will appeal to the better
instincts of technicians. An Electronic Peace Corps (EPC) could bring
these two together and offer the Third World some of the best
international technical expertise via computer networks.
Useful computers sell for around a thousand dollars, and much better,
cheaper, smaller computers are on the way. What’s more, thanks to
satellites, international communications prices are falling; and
1,000-word messages anywhere in the world, via special packet-switching
networks, could cost just $1 each.
So the EPC needn’t threaten the taxpayers with a major burden. By
essentially exporting knowledge instead of people, it in fact would
increase the impact of economic-aid dollars. The EPC could emphasize
basics like public health, agriculture, transportation, construction,
manufacturing, and communications.
In carrying out the idea, a government or international agency might
keep computer files listing:
● The skills and information required in specific underdeveloped
countries.
● People abroad who needed help.
● Those who might be able to offer it.
Most of the corpsmen wouldn’t even be computer experts—just people with
the right technical knowhow. Some might be ex-Peace Corpsmen. Others
might receive special cultural indoctrination similar to traditional
Peace Corps training.
Once in the EPC, the corpsmen might regularly correspond via E-Mail at
nights and on weekends or on occasion “talk” instantly to Third World
counterparts. Of course, not every Third World beneficiary might use a
micro. Some might submit written questions that local Peace Corps
offices could pass on electronically (one way to mitigate the language
problem).
E-Mail, incidentally, needn’t be the only form of computer
communications available through the EPC. The organization could offer
electronic bulletin boards with the names of people either needing or
offering information on subjects like biological pest control or solar
power. That way, the EPC’s beneficiaries would feel as if they had more
of a choice.
In addition, there might be ongoing computer conferences on topics of
common concern.
Obviously, the EPC wouldn’t replace foreign-aid experts in the field,
and it wouldn’t aid people _directly_ at the village level. It wouldn’t
hand out lap-sized portables to barefoot farmers. Rather, the EPC would
help engineers, doctors, scientists, and other people engaged in
development in their own countries. Corpsmen in the field would work
with local governments to make certain, for instance, that a New Delhi
slumlord didn’t use the EPC to automate his dunning operation.
Typical EPC beneficiaries might be Indians trying to set up a more
efficient grain-storage network, millions of Third World people are
starving because the food goes to the wrong places. Sometimes,
incidentally, the “wrong places” include the warehouses of thieves, and
computerized records could reduce the opportunities for corruption. Many
problems are political or economic, of course. The EPC would limit
itself to technical issues and try to be as apolitical as possible, just
as the international Red Cross focuses on relief rather than ideology.
Another EPC beneficiary might be a communications specialist hoping to
install a satellite link; for obvious reasons, better communications
might be one of the EPC’s first priorities. The EPC might help domestic
and foreign groups working toward this goal. Even countries with poor
phone lines, of course, can receive some computer messages in the large
cities.
Yet other beneficiaries could include:
● Colombian doctors who wanted to fight an epidemic with the latest
information sped over the computer lines.
● A civil engineer in Peru working on a road or bridge for isolated
villagers who hoped to sell food to cities.
● A rural-assistance administrator in Kenya. Micros could help his
staffers keep abreast of the newest, best way to dig a well or treat a
dysentery-stricken baby.
The EPC wouldn’t just promote the flow of information from countries
like the United States to the so-called lesser-developed countries.
_Among_ them, too, it would speed up the spread of practical solutions
to common problems.
Learning of an efficacious home remedy, for example, a rural-assistance
group in Ecuador might pass the information on for possible global
dissemination. It just might save the life of a child in Peru. By
keeping track of the better home remedies in the Third World, in fact,
an American drug researcher might discover something that checked out
scientifically—as has happened in the past.