BACKUP XIiconThe Micro Connection: Some Critical Explanations

When John Fuller hooked up his Heath micro over the phone lines to the Wang at his office, he had a head start on many other do-it-yourself telecommuters.

He wasn’t a computer or electronics rookie. For years he had worked around big IBM’s and Honeywells, and while telecommuting, he was a computer and management consultant with the navy. He even soldered together his H-89—a kit. And, anyway, he was communicating with another smaller computer, a Wang word processor.

Does that mean you should give up on do-it-yourself telecommuting because of the technical complexities?

No. Not at all. Before hiring a consultant, you might consider two possible sources of free advice: (1) your corporate data-processing department, if you have one, and (2) users groups, whose phone numbers you can get through dealers.

Before approaching anyone, though, learn the basics of the technology. Amodemconverts the0s from your computer into one pitch and the1s into another, and that whine, you’ll recall, goes out over the phone lines. The “mo” in “modem” stands for “modulator”; the “dem,” for “demodulator.” And a “dem” springs into action at the other end—demodulating the whine back into the1s and0s.

Modems come in two varieties,direct connectandacoustically coupled.

The direct-connect modem hooks between the phone line and your phone, or between your phone and the handset. Its whine transmits better over static-ridden lines than do acoustic couplers, but it’s normally a little more expensive, and hard to install if your phone lacksmodular plugs, the tiny plastic ones that unsnap.

Using an acoustic coupler, you cradle your handset in rubber“earmuffs.” A small speaker whines into the phone transmitter; a little microphone picks up the sound from the handset’s receiver. Acoustic couplers don’t need phones with modular plugs, obviously—a boon to traveling executives—but they might not work if the handset is oddly shaped, as it is with some of the new-style phones. Also, loud noises in the room can confuse them.

A direct-connect modem, for that reason and others, would probably be better for your regular office. Also, consider afull-duplexmodem in most cases.

No, it isn’t a modem for two-family houses. “Full duplex” is just jargon for computers jabbering back and forth, both ways, at once. Like two people on the phone. Ahalf-duplexmodem would allow just one-way communications without switching; it’s somewhat comparable to a radio with an unwieldy send-receive control. There are times, however, when half duplex would be best. Normal phone lines,voice gradeones in telephone company language, can’t handle computers jabbering at too high a speed, and half duplex may work better than full.

Like most modems for personal computers in the early 1980s, Fuller’s gizmo transmitted information at 300baudbaud—equivalent to 300 bits a second, 30 characters per second, or 360 words per minute at 5 letters a word. When telecommuting, however, you may be better off with a modem going 1,200 baud. After all, it can zip material over the phone lines at four times the speed, and that means you’re tying up your modem less on long documents. You might not be tying upyourselfif you run an operating system like Concurrent CP/M, which lets your computer handle electronic mail while you’re using it for other purposes; but a 1,200-baud modem is still a good investment if you can afford it. You may well be able to. Soon 1,200-baud modems with auto-answer features will commonly sell for well under $300.

Sent through a modem, thedata bitsare those conveying the information itself. And thestart bitsandstop bitskeep track of the beginnings and ends of your micros’ characters. The most common setting is aword lengthof 8 data bits and 1 stop bit.

Parity bitsmay help the computers check for errors caused by static and other electronic noise. Parity is said to be “even,” “odd,” or “none.” Thiserror-checkingmethod has its drawbacks. It may fail if the mistakes cancel each other out—and it’s slow since it checks every character. Somecommunications programs(the ones allowing computers to talk) lack this feature. The most common parity setting is “none”—when you tell your software not to do parity checks.

A few other wrinkles in such programs are:

FILE TRANSFER

That’s the ability to send whole files of text or data—including programs, too.

CAPTURE ABILITY

Withcapture abilityyou can keep a record of each end of a keyboard conversation with both people typing away. You tell your computer to open up abufferin its RAM—the temporary memory. The buffer captures the conversation. And if it fills up, some software will automatically “write” to your floppy disk, then reopen the buffer. Some programs won’t write to the disk at the ends of your conversations unless you command them to, meaning that the absentminded will see their bits and bytes vanish.

PROTOCOL FLEXIBILITY

Beyond changing bit numbers, etc., you may want software that can handle different kinds of protocols—sets of rules telling how computers transmit different sets of information.

One possible protocol for you to use—at least in conversations with other micros—would be theXMODEM ProtocolorWard Christensen Protocol. The receiving computer tallies up the number of bits and bytes transmitted fromblocks—tiny parts of material—and compares thischeck sumto the number that the originating machine says it sent. And if there’s a mismatch? The receiving computer asks for the block again.

You might also use no protocol at all. It’s as if you’re sending material simply by tapping away on the keyboard without any elaborate rules for the other person’s machine. You two should still, however, agree on basics like baud rate, data bits, stop bits, and parity.

Protocols usehandshakingas part of their bags of tricks. Handshaking, computers swap bits and bytes to verify that they’re on speaking terms. A common form isXON/XOFF.

Some mainframes use XON/XOFF to talk to micros and vice versa. The receiving computer gives an XOFF signal, telling the transmitting one to pause while the receiving machine “writes” to its disk. XON means, “Okay, my buffer’s almost empty. Send more!” Without thisflow control, you might overwhelm the buffer and lose information.

AUTOMATIC DIALING AND OTHER TRIMMINGS

Some modems will let the communications software dial foryou or at least let you feed the number in from your keyboard. Some also haveautomatic log-on. That lets you check onto a network or bulletin-board system without typing out your ID or password. Manyintelligent modems, by the way, even without special software, can remember and dial phone numbers automatically and spit out log-on sequences and passwords.

VERSATILITY

Want to speak to a number of computers? Then buy software allowing you to set:

◼ Baud rate (speed of transmission).

◼ Data bits.

◼ Stop bits.

◼ Parity.

◼ Terminal emulation. It means making the micro imitate popular brands of terminals.

◼ Half or full duplex. Full is most common in micro communications.

◼ The type of handshaking protocol.

Ideally, the software will also:

◼ Accommodate a variety of modem types.

◼ Designate the host—which computer will manage theecho back(which makes the typed conversation appear on both screens).

◼ Let you choose different protocols.

All those features, of course, might still not let you communicate easily with your corporate computer. It may not use theASCIIcode, for instance, which most micros do.

“Since you ASCII’d, anyway,” asPC Magazineonce punned, “those five letters are an acronym for the American Standard Code for Information Interchange.” With ASCII, an “A” is one combination of1s and0s, “B” is another, “,” is another, and so on.

When communicating with a mainframe capable of ASCII, it may not matter what brand of micro you’re running. So don’t reflexively think Big Blue for telecommuting.

The proud IBM mainframes, however, like aloof mandarins of old China, jabber away in a dialect of their own,EBCDIC—it’s similar to ASCII but different enough to cause serious problems. Now that doesn’t mean your home computer won’t work with an IBM mainframe. But it may require special programming that will translate from one set of codes to another.

Of course your corporate mainframe may also need a string ofcontrol charactersto open or close an electronic file, and here your word-processing software may matter more than your communications program.

The control characters normally are just letters tapped out in combination with the control key to give commands to your computer. They generally don’t print out on paper; they may or may not show on the screen. In this case, controls characters pass the commands on to another machine over the wires. And so you may have toembedthe control characters in your electronic files. If your word processor won’t let you embed control characters, you may not be able to communicate with some kinds of mainframes. WordStar lets you do this.

An issue more basic than control charactersisiswhether you’re usingsynchronousorasynchronous communications. The former is a staple among the big mainframes; the latter, among micros.

In synchronous communications, the two computers or modems employ timing signals to separate characters sent in one stream.

Synchronous has a big advantage. You can send at 4,800baudbaudover regular phone lines; you can’t with the asynchronous method, or at least not with late 1984 technology.

But “synch” is more expensive—the needed modems typically cost well over $1,000. Asynchronous, moreover, doesn’t require timing signals. It’s the simplest form of communications between computers; and more and more data-processing departments have added asynchronous ports for micros to dial up.

John Fuller himself was communicating not with a giant computer but a dedicated word processor in his office, which, like most, talked ASCII asynchronously. He solved other problems on his own. You may need a consultant to do what Fuller did. But take heart. It could well be worth it, what with the time and money your telecommuting may spare you and your employer.

“I’m saving gas, dressing in comfortable grubbies when I write,” Fuller said in an article about his experiences, “and with the direct connection I canprovethat I’m working. I turn out my reports faster. My computer is really paying off. Now,” said the self-deprecating Fuller, “if you’ll excuse me, I have to repel invaders from space.”

BACKUP XIIiconMODEM7: An Almost-Free and Fairly Easy Way to Talk to Other Computers

MODEM7 may be free, but itworks. With it you can talk to computers thousands of miles awayifthey’re running MODEM7 or compatible software. Normally, your only real expense is for the modem and maybe cables; you might spend as little as $100.

Using MODEM7, you can send letters, reports, or programs already on your computer disk. Or you can receive them.

You can also:

1. Communicate teletype-fashion with the other person. You can keep electronic records of what you both type and later print them out using WordStar or another word processor.

2. Call up electronic bulletin-board systems (BBSs) or plug into The Source and many other information utilities. In this case, too, you can store material on your disk and later print it out.

3. Get copies of other programs that altruistic computer buffs have placed in the public domain; you do this after you log on the BBS.

MODEM7 is a good example of free software that fills a niche; experts say it’s better than some $150 products. Most free programs are losers for the typical business. They’re either (1) games, useless except for training, (2) unreliable lemons with bugs in them, the software kind, (3) programs that might work but don’t do anything useful, or (4) fiendishly difficult challenges because the instructions are confusing and no one handy knows how to use them. But wonderful exceptions exist. Never thumb your nose at something just because it’s free. In MODEM7’s case you’ll find more happy, knowledgeable users than you will in the cases of many commercial programs.

MODEM7-style protocols have become an industry standard. Even big businesses and government agencies, including the IRS, have used MODEM7 for some purposes. It’s influenced the designs of commercial micro programs, which employ similar techniques to facilitate linkups between different brands of communications software. MODEM7 will also get along beautifully with the popular PC-TALK III “freeware” program for IBM micros and some clones. Freeware is low-cost software distributed in many cases by the users themselves; the author may request a “donation”.

Granted, MODEM7 isn’t the ultimate. The instructions included on the disk are confusing to the novice—a problem I’ll try to overcome here—and ready-to-run versions aren’t available for every computer system.

Some commercial communications software, moreover, is easier to run and can help you talk to more machines. And it may also make better use of the “smart” modems and their software so that your computer can dial up others automatically at 11:00 p.m., when the phone rates go down. You can’t do this with your cheapie modem and the plain vanilla MODEM7 described here.

But for the average computer user, MODEM7 is a good communications program to start out with. After reading the instructions that follow, you needn’t be a micro whiz to use it.

Also, youmayfind that MODEM7 is as convenient as some commercial software for simple tasks, such as quickly checking your electronic mailboxes on The Source or CompuServe.

Don’t forget: you shouldn’t pay a cent for the basic MODEM7 program itself except for the cost of a copied disk or another token fee. It’s public-domain software. So you can legally make copies for all your friends and business contacts who have modems and the same machine that you do.

But how to track down your own copy? Through CP/M user groups, you can locate versions of MODEM7 set up for different computers and disk drives, or you might find an organization of IBM owners, Kaypro fanatics, or others. The better computer stores can steer you to the right people. Incidentally, if you distrust your store, you might not want to say exactly why you’re trying to catch up with a user group. Bear in mind that the computer store isn’t going to make a profit off a free program. Some organizations, however, are selling MODEM7 at next to nothing through the mail. For instance, the Public Domain Software Copying Company says it has versions for the IBM PC and clones, all the Kaypro machines, the Morrow micros and Osborne, among others. The cost as of late 1984 was $10. The address is 33 Gold St. cl3, New York, N.Y. 10038; the telephone number, (212) 732-2565. The company also offers separate programs that will adjust stopbits and other settings, eliminating the need for programming. These programs aren’t universal. Like MODEM7 itself, they might not work for your particular machine. The Public Domain Software Copying Company also says it offers a low-cost program for the Apple II that lets it communicate with computers using MODEM7.

In addition, you might also investigate PC-TALK III, commonly available 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 12/18/80Originally Written by Ward ChristensenRevisions by Mark M. Zeiger, Jim MillsWRT —Write file to disk (from terminal mode)DEL —Erase present file (from terminal mode)RET —Return to terminal mode with no loss of dataXPR —Toggle expert mode (Menu on/off)DIR —List directory (may specify drive)CPM —Exit to CP/MS —Send CP/M fileR —Receive CP/M fileT —Terminal mode (optional file name)E —Terminal mode with echoDEFAULT DRIVE:Command:

MODEM7 as of 12/18/80Originally Written by Ward ChristensenRevisions by Mark M. Zeiger, Jim Mills

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 dataXPR —Toggle expert mode (Menu on/off)DIR —List directory (may specify drive)CPM —Exit to CP/MS —Send CP/M fileR —Receive CP/M fileT —Terminal mode (optional file name)E —Terminal mode with echo

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 theDOScommand instead of theCPMone 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. Someuse 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. TypeMODEM7after 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 letterT.

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 typeATDand a carriage return (to start getting the modems talking), and the other will typeATA(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 typeE(and the return) instead ofT(and the return).

That’s the echo mode, which you’ll recall differs from the “terminal” one.Elets 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 theTcommand rather thanE.

How to switch from the regular terminal mode to the echo mode or the reverse?

You use MODEM7’s electronic gear shift. That’sControl-E; don’t confuse it with theEused in the echo mode. You tap outthis command in other situations, too, whenever you want to return to MODEM7’s main menu. AControl-E, of course, consists of holding one finger on theCNTRLor control button and then hitting the letterE.

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. TypeControl-E.2. Tap outCPMfrom the main menu.3. Hit your return.

1. TypeControl-E.

2. Tap outCPMfrom 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 commandDOSinstead ofCPM(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’llwant 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 selectTand 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 theTmode—hitTagain, 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 forBin the rest of the steps.)

5. Now you typeB:[name of file]. Here and elsewhere don’t type the brackets surrounding the file name—and please put the file name directly afterB: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 trustyTfrom the main menu. But don’t hit your return immediately.

3. Type a space.

4. TypeB:[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 letterYwith 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. TypeControl-Eto return to MODEM7’s main menu.

8. Then, to preserve the file, “writing” to your disk, you must type outWRT, 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 hitControl-Yagain. Hit it still another time if you want to return to the “save” mode. On some successors to MODEM7 such as MDM711, aControl-Rrather than a secondControl-Ywill 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 theEor echo mode, you can shift toTwith 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, typeS B:[name of the data disk file you want to transmit—either a program or a letteror other document]. TheB:shows the file is on theBdisk. If it isn’t, just typeSand the name of the file—for instance,S MAGIC. IfMAGICis onB, typeS 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.Someversions use theTCCcommand to turn on the check-sum mode.

TO RECEIVE FROM SOMEONE WITH A MODEM7-STYLE PROGRAM

1. Fire up your modem.2. TypeR B:[new file name].3. Hit your return.

1. Fire up your modem.

2. TypeR 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 typeR 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 theA> prompt.

2. Type the word TYPE, then a space, then the name of the file—preceded by aB:, of course, if it’s on the data disk.

Immediately after the A> you should have the equivalent ofTYPE 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 substituteERAforTYPE. Say you want to eraseMAGIC. Just typeERA B:MAGIC.

TO ERASE A FILE (IF YOU’RE USING PC-DOS)

UseDELinstead ofERA. TypeDEL B:MAGIC.

TO ERASE A FILE FROM WITHIN THE MODEM7 PROGRAM

TypeDEL B:MAGICor whatever the file name is.

TO FIND OUT WHAT’S ON YOUR DISKS WHILE YOU’RE USING MODEM7

1. TypeDIRfrom the main MODEM7 menu.2. Type a space.3. TypeB:.4. Hit your return.

1. TypeDIRfrom the main MODEM7 menu.

2. Type a space.

3. TypeB:.

4. Hit your return.

This will show the contents of theBdrive, normally used for storing data.

To seeAdrive’s contents, you merely typeDIRand 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 theT B:MAGICmethod—but in the middle of the conversation you also want to check the contents of your disk via theDIRcommand?

How do you prevent theMAGICfrom 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 aWRTcommand, or the gas will leak out the top. And you can’t reenter your file by typing anotherT B:MAGIC.

But youcanget back toT B:MAGICby typingRETafter theDIRcommand.

TO GET THE MENU OFF THE SCREEN ONCE YOU KNOW THE ROPES

From the main menu, typeXPR. 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 theTmode of MODEM7 from the main menu.

2. Hit the return several times.

3. TapControl-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 theControl-Bcommand 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 asSETorTIMto 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. Zeigerand James K. Mills 11/04/80

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 SheetSnip 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 letterTand 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: TypeEand the return. For Teletype-like use when the other machine is in “Terminal.”◾TO GO FROM ONE MODE TO ANOTHER: UseControl-E. This gearshift mode returns you to the main menu.◾TO SEND MATERIAL ON YOUR DISK WITHOUT THE WARD CHRISTENSEN ERROR-CHECKING PROTOCOL: TypeControl-Tafter you’re in the terminal mode. Give the name of the file to transmit. Here, as in other cases, precede the name byB:(no space after the :) if the file is on Drive B. Hit your carriage return.◾TO RECEIVE MATERIAL WITHOUT A PROTOCOL: After typing the usualTin 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. UseControl-Yto tell your computer to start saving material; also use it to turn off the save feature. (On newer versions of MODEM7,Control-Rmight be the off switch.)IMPORTANT: After you’ve finished talking to the other machine, you must return to the main menu and typeWRTand return. Otherwise your computer won’t save the material on the disk.◾TO SEND TO SOMEONE WITH A MODEM7-STYLE PROTOCOL: TypeS, skip a space, then type the name of the file that you’ll send—with theB:before it if necessary. Hit the carriage return.◾TO RECEIVE FROM SOMEONE WITH A MODEM7-STYLE PROTOCOL: TypeR. Skip a space. Then type the name of the file where the material will show up, usingB:if needed. Hit the return.◾TO RETURN TO THE A> PROMPT: From MODEM7’s main menu, typeCPMif you’re using a CP/M version like the Kaypro one. (The IBM version substitutesDOSforCPM.) Hit your return.

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 letterTand 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: TypeEand the return. For Teletype-like use when the other machine is in “Terminal.”

◾TO GO FROM ONE MODE TO ANOTHER: UseControl-E. This gearshift mode returns you to the main menu.

◾TO SEND MATERIAL ON YOUR DISK WITHOUT THE WARD CHRISTENSEN ERROR-CHECKING PROTOCOL: TypeControl-Tafter you’re in the terminal mode. Give the name of the file to transmit. Here, as in other cases, precede the name byB:(no space after the :) if the file is on Drive B. Hit your carriage return.

◾TO RECEIVE MATERIAL WITHOUT A PROTOCOL: After typing the usualTin 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. UseControl-Yto tell your computer to start saving material; also use it to turn off the save feature. (On newer versions of MODEM7,Control-Rmight be the off switch.)IMPORTANT: After you’ve finished talking to the other machine, you must return to the main menu and typeWRTand return. Otherwise your computer won’t save the material on the disk.

◾TO SEND TO SOMEONE WITH A MODEM7-STYLE PROTOCOL: TypeS, skip a space, then type the name of the file that you’ll send—with theB:before it if necessary. Hit the carriage return.

◾TO RECEIVE FROM SOMEONE WITH A MODEM7-STYLE PROTOCOL: TypeR. Skip a space. Then type the name of the file where the material will show up, usingB:if needed. Hit the return.

◾TO RETURN TO THE A> PROMPT: From MODEM7’s main menu, typeCPMif you’re using a CP/M version like the Kaypro one. (The IBM version substitutesDOSforCPM.) Hit your return.

Back to Index Next