Dec 312017
 
The original, now pretty obsolete.
File PCTALK.ZIP from The Programmer’s Corner in
Category Communications
The original, now pretty obsolete.
File Name File Size Zip Size Zip Type
PC-TALK.DOC 119424 28205 deflated
PC-TALKB.DOC 72320 21330 deflated
PC-TALKB.EXE 84224 55135 deflated
PCTB.MAC 13824 5120 deflated

Download File PCTALK.ZIP Here

Contents of the PC-TALK.DOC file












=== The PC-TALK III User's Guide starts on the next page ===























































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---------------------------------------------------


===== PC-TALK III =====

Communications Program for The IBM Personal Computer



=== User's Guide by Andrew Fluegelman ===

---------------------------------------------------























=== FREEWARE - P.O. Box 862, Tiburon, CA 94920 ===

Copyright (c) 1983 The Headlands Press, Inc.













--- PC-TALK III User's Guide ---






=== Contents ===




To Users of PC-TALK version 2.00 4
Summary of Commands 6
Making Working Copies of PC-TALK 9
Starting PC-TALK 11


=== Screen, Keyboard, and Printing ===

Echo: Alt-E 13
The Width Alarm: Alt-W 13
Printscreen: Shift-PrtSc 14
Simultaneous Printout: Ctrl-PrtSc (or Ctrl-PgUp) 14
Screendump: Alt-S 16
Clearscreen: Alt-C 16


=== Receiving and Transmitting Files ===

Receiving a File: Alt-R (or PgDn) 17
Transmitting a File: Alt-T 19
The Binary transmit option: '=b' 20
The Pacing transmit option: '=p' 21
XMODEM Transmitting and Receiving: '=x' 24
A Note on Communications Terminology 26


=== More File Commands ===

Status Messages: Alt-M 27
Viewing a File: Alt-V 28
Deleting a File: Alt-Y 29
The Logged Drive: Alt-L 29
File Specification Conventions 30


=== Dialing ===

The Dialing Directory: Alt-D 32
Adding to the Directory 34
Other Directory Options 35
Auto-dialing 36
Long Distance Services: '+#' and '-#' 36
Manual Dialing: 'm' 38
Redialing: Alt-Q 38
Stripping and Converting Characters 39
Pacing Instructions 41


--- FREEWARE - P.O. Box 862, Tiburon, CA 94920 ---





--- PC-TALK III User's Guide ---







=== Parameters and Defaults ===

Communications Parameters: Alt-P 44
Program Defaults: Alt-F 45


=== Input Strings ===

The Function Key Directory: Alt-K (or Alt-J) 52
Using the Function Key Assignments 53
Temporary Alt Keys: Alt-1 through Alt-0 55


=== Miscellaneous Features and Commands ===

Elapsed Time: Alt-Z 58
Exit: Alt-X 58
Sending a Break Signal: Ctrl-End 58
Command Summary: Home key 59
Toggle Commands 59


=== More Applications and Advanced Features ===

XON/XOFF: Alt-O 60
Communications Errors: <<>> and <> 60


=== PC-TALK III File Information ===

Programming Information 63
Copying PC-TALK 64
Modifying PC-TALK 64
Thank You! 66
FREEWARE 67

Appendix A: Communications Parameters 69
Appendix B: The XMODEM Protocol 70














--- FREEWARE - P.O. Box 862, Tiburon, CA 94920 ---





--- PC-TALK III User's Guide --- 4





=== To Users of PC-TALK version 2.00 ===


This brief summary is to acquaint you with the new or revised
features in PC-TALK version III. Each of these features is
described in detail in the documentation.


1. PC-TALK III is supplied in an interpreter BASIC source code
version (PC-TALK.BAS) for systems with 64K of memory and a
compiled BASIC version (PC-TALK.EXE) for systems with 128K or
more of memory. The .EXE version will give optimum performance
and is recommended if you have sufficient memory.

To run PC-TALK ...
-- If you have 64K of memory, type 'TALK64' .
-- If you have 128K or more of memory, type 'TALK128' .

2. The 'fast' mode from previous versions has been eliminated.
All features now operate fully at up to 1200 baud in both the
BASIC interpreter and the BASIC compiled version.

3. A Screendump feature (Alt-S) now permits writing the contents
of the screen to a disk file.

4. A margin Width feature (Alt-W) signals when keyboard input has
exceeded a specifiable right margin.

5. Three Transmit options are now provided for transmitting
binary files (=b), for transmitting files with line pacing (=p),
and for transmitting and receiving files using the XMODEM error-
checking protocol (=x).

6. The Dialing Directory (Alt-D) has been expanded to sixty entry
capacity. Optional parameters allow selective character
stripping and/or converting and for storing pacing instructions
for each entry.

7. An auto-redial feature has been added (Alt-Q).

8. There are now forty possible permanent input strings (Alt-K).
These permanent strings are now stored to be input with the
Function keys in combination with the Alt, Shift, and Ctrl keys.

9. The temporary input strings (Alt-=) have been switched to the
ten key combinations Alt-1 through Alt-0.

10. Because of the expansion of the Dialing Directory and the
Function Key Directory, the special keys for dialing CompuServe
and the Source and for sending specific commands to these
networks have been eliminated.



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--- PC-TALK III User's Guide --- 5


11. A routine has been added for interactively specifying and
changing all program defaults while the program is running (Alt-
F).

12. The conventions for specifying files and input strings within
the program have been standardized. Control characters can now
be specified as part of input strings.


Even if you are familiar with earlier versions of PC-TALK, it is
recommended that you read through the entire documentation, most
of which has been thoroughly revised.

The PC-TALK III User's Guide is 70 pages long. It is supplied on
a file called PC-TALK.DOC, which is either on the program disk,
or on a separately labeled disk if two disks have been provided.

To print the User's Guide, see the instructions at paragraph 9 of
the following section, "Making Working Copies of PC-TALK."


I hope that you find PC-TALK III to be more useful, and just as
friendly, as version 2.00.


- Andrew Fluegelman































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--- PC-TALK III User's Guide --- 6





=== Summary of Commands ===


Alt-E When activated, Echoes keyboard input to the
screen. (Toggle) USE IF YOUR KEYBOARD INPUT IS
BLANK OR DOUBLE.


Shift-PrtSc Prints current screen contents at any time.


Ctrl-PrtSc When activated, simultaneously prints all
(or Ctrl-PgUp) screen output to the printer. (Toggle)


Alt-R Starts/stops routines to Receive input from
(or PgDn) the communications port to files on disk.


Alt-T Starts/stops routines to Transmit files from
(or PgUp) disk through the communications port.


Alt-V Starts/stops routine to View a file which has
been saved to disk.


Alt-Y Permits deleting a file from disk.


Alt-D Calls up the Dialing Directory. Permits
storing parameters for 60 phone numbers and
auto-dialing.


Alt-Q Redials the last number dialed.


Alt-M When activated, sends status Messages as part
of the transmit and receive routines.
(Toggle)


Alt-P Permits changing the communications Parameters.


Alt-F Permits temporary or permanent changes to the
program defaults.






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--- PC-TALK III User's Guide --- 7




Alt-K Calls up the Function Key Directory. Permits
(or Alt-J) specifying up to 40 Function key combinations
to input permanent i.d. #s and logon
sequences.


Alt-= Permits programming of keys Alt-1 through Alt-0
(Alt-equals) as temporary input while the
program is running.


Alt-S Writes contents of the screen to a file
SCRNDUMP.PCT on the Logged drive.


Alt-L Changes the Logged drive for file specifications.


Alt-W Sets an optional Width alarm for keyboard input.


Alt-Z Displays the elapsed time for the current call.


Alt-C Clears the screen.


Alt-O Permits re-starting transmission manually when
the remote computer has sent an XOFF signal.


Alt-X Exits the program and returns to DOS.


Ctrl-End Sends a 'Break' signal to the remote computer.


Home Displays an on-screen summary of these commands.


















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--- PC-TALK III User's Guide --- 8




File Specification Commands:


? or ?+[spec] - When given as response to a file specification,
lists files currently on logged or specified
drive. Wild card characters * and ? are allowed.


- When given as response to file specification,
re-inputs the last file Transmitted, Received,
or Viewed.


- When given as response to file specification,
cancels Transmit, Receive, View, and Delete routines.


=p[n][c] - When added to the end of a Transmit file
specification, paces transmission one line at a
time--either every n seconds or after the
prompt c is received.


=b - When added to the end of a Transmit file
specification, permits transmitting file in
binary format.


=x - When added to the end of a Transmit or Receive
file specification, invokes the XMODEM error-
checking protocol.



String Specification Commands:


} - Signifies a carriage return as part of the string.


- Clears a previously specified string.


- Leaves a previously specified string unchanged.











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--- PC-TALK III User's Guide --- 9





=== Making Working Copies of PC-TALK ===


Before you use your PC-TALK program disk(s), you should make a
working copy of the program. Follow these steps carefully:


(Please note that you may have been provided with two disks,
marked "PC-TALK.III" and "PC-TALK.DOC", or a single disk marked
"PC-TALK.III". If you have been provided with a single disk, it
contains all of the necessary PC-TALK files.)


1. Place your own copy of PC-DOS (versions 1.00, 1.10, or 2.00)
in drive A and press the Ctrl-Alt-Del keys simultaneously. Enter
the date and time, when required. You should see the DOS A> prompt.


2. Place a blank disk (or one that can be REFORMATTED) in drive B.


3. Type 'FORMAT B:/S' . This will format the disk in
drive B with the DOS system and command files.


4. Type 'COPY BASIC.COM B:' . This will copy the file
BASIC.COM to the disk in drive B.


5. Now remove the DOS disk from drive A and insert the PC-TALK.III
program disk in drive A.


6. Type 'COPY *.* B:' . This will copy all the files from
the program disk onto the disk in drive B.


7. Remove the program disk from drive A and store it in a safe
place. Take the disk from drive B and label it "PC-TALK.III".
Use this as your working program disk.


8. If you have been provided a separate disk marked "PC-TALK.DOC",
repeat steps 1 through 7 above, using the PC-TALK.DOC disk.










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--- PC-TALK III User's Guide --- 10




9. Before you start using the program, please make sure that you
have printed and read the PC-TALK III User's Guide.

-- If you have been provided with two disks, place the working
copy of the PC-TALK.DOC disk in drive A.

-- If you have been provided with one disk, place the working
copy of the PC-TALK.III disk in drive A.

Now type 'PRINTDOC' and follow the screen prompts. This
will print the file PC-TALK.DOC.


10. You are now ready to run PC-TALK. Place the working program
disk marked PC-TALK.III in drive A and proceed with the following
instructions, "Starting PC-TALK".







































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--- PC-TALK III User's Guide --- 11






=== Starting PC-TALK ===



First make sure that PC-DOS is loaded so that you see the A>

prompt. Place the disk marked "PC-TALK.III" in drive A. Then...


-- If you have 64K of memory, type 'TALK64' .

This will load and run the BASIC file PC-TALK.BAS.


-- If you have 128K or more of memory, type 'TALK128' .

This will load and run the compiled BASIC file PC-TALK.EXE.

You can also run PC-TALK.EXE by simply typing 'PC-TALK' .



When you see the prompt "===Proceed ..." PC-TALK is in operation.

At this point, you should turn on your modem, if you have not

already done so.


-- If you have a direct connection modem:

You can proceed to send the appropriate modem commands

directly from the keyboard. (Making use of auto-dialing

features is described in the documentation under "The Dialing

Directory.")


-- If you have an acoustic modem:

Dial the phone number you wish, place the telephone receiver

in the modem cradle, and switch to 'Data'. Once you have made

a connection, you can proceed with keyboard instructions.


At this point, your PC has been set up as a "dumb" terminal,




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--- PC-TALK III User's Guide --- 12


connected with the remote computer. You can send information to

the remote computer by typing on the keyboard, and see

information sent by the remote computer displayed on your screen.


NOTE: IF YOU CAN'T SEE YOUR KEYBOARD INPUT, press Alt-E to put

the program into Echo mode.


PC-TALK is capable of doing many "smart" things too, such as

receiving and sending disk files, dialing phone calls, and

storing commands for future use. All the program features are

described in the documentation, which is contained in a file on

the program disk called PC-TALK.DOC.


********** PLEASE PRINT AND READ THE DOCUMENTATION! **********

This will save you from having unanswered questions and greatly

increase your enjoyment of the program.


To print the documentation, follow these instructions:


-- If you have been provided with two disks, place the working

copy of the PC-TALK.DOC disk in drive A.

-- If you have been provided with one disk, place the working

copy of the PC-TALK.III disk in drive A.


*** Now type 'PRINTDOC' and follow the screen prompts.

This will print the file PC-TALK.DOC. Please take some time to

read through the documentation before trying to use the program.










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--- PC-TALK III User's Guide --- 13






=== Screen, Keyboard, and Printing ===



Echo: Alt-E


With some systems, the remote computer will send back to your

screen the characters you type at the keyboard. This is known as

"full duplex" communications. In other cases, the remote

computer will not send back the characters you type ("half

duplex"). You can adjust for either of these situations with the

Echo option, which is toggled on and off by pressing Alt-E.


If you can't see your own keyboard input on the screen once

communications are in progress, turn on the Echo option (Alt-E).

This might make your modem commands appear as double characters,

but should produce proper screen output during communications.


If your regular communications input appears as double charac-

ters, disable the Echo function by pressing Alt-E.

----------------------------------------


The Width Alarm: Alt-W


Many remote systems place a limit on the length of a line which

can be entered. It can be a nuisance to have to keep track of

this limit when typing on the screen.


As you send information using the keyboard, you will notice that

the program beeps when you type more than 70 characters on a

line. This is the Width alarm feature. It operates like the


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--- PC-TALK III User's Guide --- 14



margin alarm on a typewriter.


The beeps will continue until you press the key or until

you have typed more than ten additional characters. The beeps

are merely reminders--the characters are still sent as typed,

even if the alarm sounds.


You can specify a different margin width by pressing Alt-W. If

you want to disable the Width alarm, enter 0 (zero) as the value

for the margin width.

----------------------------------------


Printscreen: Shift-PrtSc


At any time during program operation, hitting the Shift key in

combination with the PrtSc key will print the contents of the

screen to the printer. (This is the regular DOS function).

----------------------------------------


Simultaneous Printout: Ctrl-PrtSc (or Ctrl-PgUp)


You can also produce simultaneous printout while communications

are in progress by pressing Ctrl-PrtSc or *ctrl-PgUp. A message

will indicate "===PRINTOUT ON===" and all subsequent information

displayed on the screen will be sent to the printer as well.


You can disable the Printout function by hitting Ctrl-PrtSc or

Ctrl-PgUp again. A message "===PRINTOUT OFF===" will be displayed

and the Printout function will be toggled off. The Printout

function can be turned on and off without disturbing

communications.


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--- PC-TALK III User's Guide --- 15




If the Printout function is invoked when the printer is not

turned on, a message "===CHECK PRINTER===" will appear, the function

will remain off, and communications will continue.


**Applications Notes:

Running the Printout option may slow communications because many

printers cannot keep pace with the communications rate. If you

are communicating at 1200 baud (described below under "Commu-

nications Parameters") you should not try to run simultaneous

printout, as you will likely overflow the communications buffer.

If this happens, the program will attempt to recover by turning

off the Printout function.


A new feature in PC-TALK III buffers the printout to take correct

account of backspace characters within each line.


If you happen to run the BASIC interpreter version of the program

under BASIC 2.0, the Ctrl-PrtSc key will turn on continuous

printing, but not with PC-TALK's support features described

above. In this case, you should use the Ctrl-PgUp key to control

the Printout function. (Note, however, that if you have enough

memory to run BASIC 2.0, you will get better performance by

running the compiled version of the program, PC-TALK.EXE. See

"Starting PC-TALK", above.)

----------------------------------------









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--- PC-TALK III User's Guide --- 16





Screendump: Alt-S


Another new feature in PC-TALK III allows you to dump the

contents of the screen to a disk file at any time by pressing

Alt-S.


When you start the program, the Screendump file is a file on

drive B called SCRNDUMP.PCT. Each time you press Alt-S, the

screen contents is appended to that file. The date and time is

automatically recorded for each screendump.


You can specify a different Screendump file from within the

Default routine (described below).

----------------------------------------


Clearscreen: Alt-C


Pressing Alt-C will clear the screen at any time. This command

does not send any character or signal to the remote computer.






















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--- PC-TALK III User's Guide --- 17






=== Receiving and Transmitting Files ===



Receiving a File: Alt-R (or PgDn)


The file receiving routine permits you to save information you

receive from a remote computer on your own disk files. It

operates manually and requires no special protocol.


To start the Receiving routine, press Alt-R. The program will ask

for a drive and filename under which to receive the file.


Once the Receiving routine is in operation, you will see a

reminder on line 25 of the screen indicating the name of the file

being received. From that point on, all information passing

through the communications port, whether it is being typed from

your keyboard or coming from the remote computer, will be saved

to the specified disk file.


To guard against accidentally erasing existing files, if a

filename is specified that already exists on the disk, the new

input will be appended to the end of the existing file.


To terminate receipt of the file, press Alt-R once again. You

can receive different files to disk, or keep appending to the

same disk file, many times during a communications session.


**Applications and Advanced Features:

Certain remote computer systems may send unwanted characters to

your computer. If you have need to strip or convert certain


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--- PC-TALK III User's Guide --- 18



characters as they are being received, you can specify those

characters with the Strip option described below.


PC-TALK can receive binary files without any special file

receiving specification. You do have to be careful, however, to

open and close your file for receiving so that you do not receive

any extraneous characters or messages from the remote computer.


The recommended procedure for receiving binary files is to have

the Message option (described below) ON for the receiving

computer and OFF for the transmitting computer and for the

transmitting computer operator to give the receiving computer

ample time to open and close the file. Please note also that if

you want to receive a binary file, you must not have any

stripping in effect and must be communicating at 8 data bits.

(These communications parameters are described below.)


PC-TALK is also capable of receiving files using the XMODEM

error-checking protocol. The use of this protocol is described

separately below.

----------------------------------------


















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--- PC-TALK III User's Guide --- 19





Transmitting a File: Alt-T


Just as you can receive information and store it on disk files,

you can transmit information from your disk files to the remote

computer.


The regular file transmitting routine is "plain vanilla" -- it

requires no special protocol from the remote computer. It can

therefore be used to send your disk files to virtually any other

personal computer, to network bulletin boards, and to many large

computer systems.


To start the Transmit routine, press Alt-T. The program will then

ask for the specification of the file to be transmitted. Once you

have given the specification and press the key,

transmission of the file will proceed.


Once transmission is in progress, you will see the text of your

file displayed on the screen. Line 25 of the screen will indicate

the name of the file being transmitted and the approximate

minutes remaining to complete the transmission. The transmission

routine will terminate automatically at the end of the file.


You can terminate transmission manually at any time by pressing

Alt-T.


**Applications and Advanced Features:

The transmitting routine can be used to send files to personal

computers and to network bulletin board services. When you are



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--- PC-TALK III User's Guide --- 20


ready to send your file, start the Transmit routine (Alt-T),

specify the file to be sent, and press . None of the

specification prompts you see on your screen will be sent to the

remote computer -- only the text of your file.


If the remote computer requires a special character to begin

receipt of the file, it should be sent manually via the keyboard

prior to giving the Alt-T command.

----------------------------------------


**File Transmitting Options:


PC-TALK offers some advanced transmit options for sending binary

files, for pacing transmission, and for transmitting with an

error-checking protocol. In each case, the option is invoked by

adding an equals sign plus the letters 'b', 'p', or 'x' to the

end of the file specification. Each of these options is

described below; however, it is recommended that you do not try

these options until you are familiar with the basic features of

the program.

----------------------------------------


The Binary transmit option: '=b'


PC-TALK permits transmitting binary files (.COM and .EXE files

and BASIC programs not saved in ASCII format). To transmit a

binary file, add '=b' to the end of the transmit file

specification.


For example, to transmit the file MYFILE.COM, you would

give the transmit file specification by typing


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--- PC-TALK III User's Guide --- 21



'MYFILE.COM=b' . (It does not matter whether the

'b' is typed in upper or lower case.)


When you transmit using the binary option, the text of the file

will not be displayed on the screen.


You must be communicating at 8 data bits (No parity) to transmit

a binary file.

----------------------------------------


The Pacing transmit option: '=p'


Because of the increased performance of this version of PC-TALK,

the Transmit routine may operate too fast for some remote

computers (such as the Source and many mainframe systems). PC-

TALK now offers a Pacing option to slow down transmission of

files. This feature will send your file to the remote computer

one line at a time, pausing between lines.


To invoke the Pacing option, specify '=p' following the

specification of the file to transmit; e.g., 'MYFILE.123=p'.

At this point you have two options:


-- If you want the line pacing to be governed by a time delay,

enter a number following the '=p' to indicate how many seconds to

pause between transmission of lines of your file.


For example, if you specified 'MYFILE.123=p2', the

program would pause approximately two seconds between

lines.




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--- PC-TALK III User's Guide --- 22


You can enter a fractional number, such as '=p.5' for a half-

second pause. You should experiment with your remote system to

determine the optimum time delay for pacing.


-- The second line pacing option waits for a prompt from the

remote computer before sending the next line. This is invoked by

specifying the character(s) for the prompt immediately following

the '=p'.


For example, specifying 'MYFILE.123=p?' would cause the

program to wait for the receiving computer to send a

question mark before the program continued transmitting

the next line. You can specify a control character as

the prompt; for example, '=p' followed by a control-R

would cause the program to wait for an ASCII 19.


When paused for a prompt in the line pacing transmit mode, you

always have the option of proceeding with transmission manually

by hitting the space bar, or terminating transmission by hitting

Alt-T.


You can store pacing instructions as one of the parameters in the

Dialing Directory (described below).


**Technical Note:

The Pacing option will automatically strip line feed characters

(ASCII 10) during transmission. It will also add a space

preceding each carriage return (ASCII 13). In other words, each

carriage return/line feed sequence (ASCII 13/10) in the file will

be transmitted as a space/carriage return (ASCII 32/13). The



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--- PC-TALK III User's Guide --- 23


Pacing routine will then either pause for the specified time

delay, or wait for the specified prompt before sending the next

line.


If for some reason you want to strip line feeds and pad carriage

returns with spaces during transmission, but don't want to pause

with either a time delay or to wait for a prompt, just add '=p'

to the file spec. The Pacing routine will proceed without

stopping. (Please note that if you specify '=p0' as the pacing

option, the program will wait for a '0' (zero) from the remote

computer before proceeding with the next line.)


The pacing option is a powerful feature that greatly extends the

versatility of PC-TALK in communicating with a variety of remote

computer systems. However, it is not recommended that you try to

use transmit pacing unless you know of a specific need for it.


One common application in which transmit pacing is useful is

transmitting files to the Source using Telenet or Tymnet.

Depending on how heavily the system is being used, you may find

it necessary to pace transmission with a 2- or 3-second delay

between lines to make sure that your file is properly received by

the remote system.

----------------------------------------














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--- PC-TALK III User's Guide --- 24





XMODEM Transmitting and Receiving: '=x'


One of the noteworthy features in PC-TALK III is the inclusion of

the XMODEM protocol originally developed by Ward Christensen.

The purpose of the XMODEM protocol is to guard against

inaccuracies in file transfer caused by bad signals on the

telephone line. It is a "hand-shaking" and error-checking

protocol that ensures accurate transmission and receipt of data

and binary files. The protocol is in wide use today among a

variety of microcomputer systems.


The XMODEM protocol can be used for both transmitting and

receiving files. In each case, you should add '=x' to your file

specifications; for example, 'MYFILE.123=x'.


Once you have entered the file spec and pressed , you will

see a message indicating that the protocol is in effect and the

notice, "*** Holding for Start..." The rest of the file transfer

occurs automatically.


If you are transmitting, line 25 of the screen will indicate how

many blocks (of 128 bytes) comprise the file. You will see a

message "Sending block # n", followed by the message "- verified"

when the remote computer has successfully received that block.

The file transfer will proceed, block by block, until the end of

the file is reached. The transfer will then terminate

automatically.





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--- PC-TALK III User's Guide --- 25


If you are receiving, you will see the same "*** Holding for

Start..." notice, followed by messages "Received block # n -

verified" as each block is received. You will not see any

indication of how long the file is, but the receiving routine

will terminate automatically.


If the program detects an error while transferring the file, you

will see either a message "**Re-sending block..." in transmit

mode, or a variety of error messages in receive mode. In either

case, the program will attempt to recover, indicate when the

transmission/receipt is verified, and continue with the transfer.


In some cases, the program will not be able to recover,

particularly if the line signal is degraded. The transfer will

automatically terminate after repeated errors. You can also

terminate manually at any time by pressing Alt-R or Alt-T.


If the XMODEM transfer does not succeed, please do not assume

that there is something wrong with your computer or with PC-TALK.

It is suggested that you hang up, re-establish communications

over a new line, and try again.


To operate with the XMODEM protocol, you must be communicating at

8 data bits, No parity (Communications Parameter options 2 or 4

-- see below). Both computers must have communications software

capable of running the XMODEM protocol.


The XMODEM routine in PC-TALK III has been tested with other

implementations of the protocol and should give you good results.

If the other computer is running PC-TALK III, you can be



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reasonably assured of a rapid and accurate file transfer.


The XMODEM routine operates automatically. For those who are

interested, a brief technical description of how the file

transfer takes place can be found in Appendix B at the end of

this documentation.


Before leaving the subject of XMODEM, it is appropriate that

acknowledgment be given to Ward Christensen, who originated the

protocol and who has been a landmark pioneer in computer

communications.

----------------------------------------



A Note on Communications Terminology --


The PC-TALK prompts and documentation generally avoid use of the

words 'uploading' and 'downloading'. A convention in the

mainframe world has been to use 'uploading' to refer to

transmitting a file to a remote computer and 'downloading' to

refer to receiving a file from a remote computer. In the case of

two microcomputers communicating with each other, the notion of

'up' and 'down' seems less appropriate.


For those who feel more comfortable with the mainframe terms, PC-

TALK offers the option of using the PgDn key (in addition to Alt-

R) to start and stop Receiving a file and the PgUp key (in

addition to Alt-T) to start and stop Transmitting a file.

---------------------------------------






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=== More File Commands ===



Status Messages: Alt-M


The Message option (invoked with Alt-M) will send messages to the

remote computer when receiving and transmitting files.


When receiving a file with the Message option in effect, the

message "===READY TO RECEIVE===" will be sent to the remote

computer as soon as the receiving routine is in operation and

"===FILE RECEIVED===" when the receiving routine is terminated.


During transmission, the messages are "0 '===START OF FILE==="

and "65529 '===END OF FILE===" or, if the file was terminated

prematurely, "===TRANSMISSION OF FILE TERMINATED===". These

messages will appear on the remote computer's terminal, signalled

with a "bell" or "beep".


**Applications and Advanced Features:

The best use of the Message function is for the receiving

computer to have Messages ON and the transmitting computer to

have Messages OFF. That way, the transmitting computer knows

when the receiving computer is ready to receive the file.


The numbers in the Transmit messages do make it possible to have

the Message function active when transmitting a BASIC file in

ASCII format. The messages then become remarks in the

transmitted program.



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The Message function should not be used when transmitting or

receiving files to or from a network or mainframe system.


The Receive and Transmit file specification prompts are always

displayed on your screen, regardless of whether the Message

option is in effect. These local messages are not transmitted and

do not interrupt communications.

---------------------------------------------



Viewing a File: Alt-V


PC-TALK permits you to view any file which is on your disk drives

while the program is running. This feature makes it possible for

you to refer to files on disk while communications are in progress.


To View a file, press Alt-V. The program will ask for file

specifications in the same manner as the procedures for

transmitting and receiving files.


Once Viewing is in progress, twenty lines of the file will be

displayed on the screen at a time. To see more of the file,

press the space bar. To cancel the Viewing routine, press Alt-V

again.


The text of the file you see displayed on your screen will not be

sent to the remote computer.


**Applications and Advanced Features:

If the remote computer sends you information while you are

viewing a file, that information will be stored in the



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communications buffer. A continuous stream of information from

the remote computer could overflow the buffer. You should

therefore view a file only during a pause in communications.


You can print the contents of the file as you are viewing it

by turning on the Printout function (Ctrl-PrtSc) before giving

the Alt-V command. You can also print selective portions of the

file by using the Printscreen function (Shift-PrtSc).

---------------------------------------------



Deleting a File: Alt-Y


You can delete any file from your disk(s) while communications

are in progress. Press Alt-Y and follow the file specification

prompts. You will be shown the first five lines of the file and

then asked whether you are sure that you want to delete the file.

If you respond 'y' to the prompt, the file will be permanently

deleted from your disk. Be careful!

----------------------------------------



The Logged Drive: Alt-L


For the Transmit, Receive, View, and Delete routines, the program

assumes a default "Logged" drive if no drive is given as part of

the file specification prompts. Initially, this is drive B.


For example, if drive B is the Logged drive and you

respond to a file specification prompt with just

'MYFILE', the program will automatically look for a file

'B:MYFILE'. If you want to transmit, receive, or view a


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file on drive A, you should respond to the file

specification prompt with 'A:MYFILE'.


To change the Logged drive during program operation, press Alt-L

and follow the instructions. The Logged drive can also be

changed as part of the Default modification routine (described

below).

----------------------------------------



File Specification Conventions --


PC-TALK III uses a standard set of commands for responding to

file specification prompts in the Receive, Transmit, View, and

Delete routines.


If you do not include a drive indicator as part of the

specification (e.g., 'MYFILE.123'), the program will assume that

the file is to be located on the Logged drive (see above).


If you would like to see a list of the files presently on the

Logged drive, you can type a question mark in place of the file

spec. You will be shown a listing of the files on the Logged

drive. To see the files on another drive, type a question mark

followed by the letter designation of the drive.


For example, if drive B is the Logged drive and you

respond to a file spec prompt with '?', you will be

shown a list of the files on drive B. If you respond

with '?a', you will be shown a list of the files on

drive A.


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You can also use the 'wild card' characters '*' and '?' as part

of these file listing requests.


For example, if you respond to the file spec prompt with

'? a:*.bas', you will be shown a list of all the files

on drive A with the extension '.bas'.


If you decide you do not want to continue with the Receive,

Transmit, View, or Delete routines once you have made your

initial request with Alt-R, -T, -V, or -Y, press at the

file spec prompt and the routine will be cancelled.


If the Receive, Transmit, or View routines are invoked more than

once during a communications session, you can hit the space bar

in response to the file spec prompt, and the name of the last

file specified for receiving, transmitting, or viewing will

appear. You can then either press and continue

receiving, transmitting or viewing that file, or modify that file

spec before pressing .

---------------------------------------------



















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=== Dialing ===



The Dialing Directory: Alt-D


The Alt-D command calls up the Dialing Directory, which is one of

PC-TALK'S most useful features. The Directory can list up to

sixty names and phone numbers, plus communications parameters and

echo, message, stripping and pacing instructions for each entry.


The following instructions will first show you how to place names

and phone numbers into the Directory and then describe how to use

the Directory as part of your standard communications routines.


When the Directory is called up for the first time, all entries

will be blank. To add names and phone numbers to the Directory or

to revise the Directory later on, enter 'r' at the "Dial entry

#:" prompt. (It doesn't matter whether you use lower or upper

case.) Then enter the entry number you want to add or revise.


To add/revise entries, type in the name, followed by , and

the phone number (area codes optional), followed by . Up

to 36 characters may be specified for the phone number; only the

rightmost 14 characters will be displayed in the Directory.


You will then be asked whether the communications parameters are

"ok". If 300 baud-even parity-seven data bits-one stop bit is

acceptable (this is the most common protocol), type 'y' .

If you respond with 'n', you will be asked to specify



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communications parameters. The program will not let you dial

using invalid parameters. (If you run into trouble, re-specify

'300-E-7-1'.)


The revise entry routine will then ask whether you want to echo

characters to the screen (common for inter-personal computer

communications, but usually not necessary for public networks

such as CompuServe and the Source), and whether you want to send

status messages as part of the file Receiving and Transmitting

routines (see above). Press after responding to each

prompt.


The routine will then ask whether you want to strip or convert

characters for that entry. It is recommended that you respond

with 'n' unless you have a special applications need. (See the

explanation of the Stripping option below.)


Finally, the routine will ask whether you want to specify a

Pacing instruction for that entry.


If you want to specify a Pacing instruction, enter either a time

delay number or a pacing prompt character in response to the

"Pacing? p=" prompt. Respond with 'n' if you do not want

any pacing in effect for that entry. It is recommended that you

do not specify a Pacing instruction unless you know of a specific

need for it.


If you make an error specifying a directory entry, type 'n'

at the final "ok?". You will be taken through the

specification routine again. For each parameter, you can either



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specify a new value or press to leave the present value

unchanged.


After you have responded with 'y' to the final "ok?" prompt, the

Directory will clear, showing the new information you input. The

name, phone number, and communications specs will be permanently

stored in a separate file on your program disk named PC-TALK.DIR.

----------------------------------------


Adding to the Directory --


As indicated above, specifying communications parameters, echo,

message, stripping, and pacing can all be considered advanced

features that need not be dealt with the first time you use the

program. The following example lists the commands for merely

adding a name and phone number to the Directory.


1. Press Alt-D. You will see Page 1 of the Directory displayed
and the prompt "Dial entry #:".


2. Type 'r' . You will see the prompt "Revise/add entry #:".


3. Type '1' . You will see the prompt "Name:".


4. Type the name you want for entry #1 (maximum 20 characters)
followed by . You will see the prompt "Phone number:".


5. Type the phone number you want for entry #1 (maximum 36
characters) followed by . You will see the prompt
"Communications parameters ok (y/n)?".


6. For this example, the parameters are ok, so type 'y' ,
or just press . You will see the prompt "Echo on (y/n)?".


7. Type 'n' or just press . You will see the
prompt "Messages on (y/n)?".


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8. Type 'n' or just press . You will see the
prompt "Strip/convert characters (y/n)?".


9. Type 'n' or just press . You will see the
prompt "Pacing? p=".


10. Type 'n' or just press . You will see the
prompt "Is entry #1 ok (y/n)?".


11. Type 'y' or just press . You will see Page 1
of the Directory re-displayed with the name and phone number you
just entered.


12. Repeat the above steps for each name and phone number you
want to add to the Directory.

----------------------------------------



Other Directory Options --


Although the Directory has a capacity of sixty entries, the

screen will display only fifteen entries at a time. You can

"page" forward or back through the directory by entering 'f' or

'b' at the initial "Dial entry #:" prompt.


You can dial any entry, regardless of whether it is displayed.

However, you can revise only those entries that are on the

displayed page of the Directory.


If you enter 'c' at the "Dial entry #:" prompt, you have the

option of clearing Directory entry #s within the range 1-60. You

will be asked "Are you sure?" before your selected entries are cleared.


----------------------------------------




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Auto-dialing --


The Dialing Directory will automatically dial a Directory entry

if your modem supports this function.


The first time the Directory is called up, you will see a notice

that says "modem dialing command = ATDT". This is the command

used by the D.C. Hayes Smartmodems for using touch tone dialing.


To specify a different dialing command--such as for pulse dialing

or for another auto-dial modem--enter 'r' to revise the

Directory and then type 'm' at the "Revise/add entry #:"

prompt. Then type your desired dialing command, followed by

. (The Smartmodem command for pulse dialing would be

'ATDP'.)


Whatever modem dialing command you specify will be permanently

stored in the Directory file (until revised again).


Once the appropriate dialing command has been entered in the

Directory, you can have the program dial phone numbers

automatically. Simply type the Directory entry # you wish to

call, followed by . The phone number listed for that entry

will then be dialed.

----------------------------------------


Long Distance Services: '+#' and '-#'


The Dialing Directory is also able to route calls through

supplemental long distance services such as Sprint and



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MCI. Two different service numbers can be stored in the

Directory, which are listed in the Directory as '+#' and '-#'.


To add a long distance service number to the Directory, type 'r'

at the "Dial entry #:" prompt. Then type '+' or '-' plus

at the "Revise/add entry #:" prompt. You can then

specify a long distance number command.


When entering the long distance number, include both your local

access number and your i.d. number. Separate the two numbers with

your modem's "pause" command indicators (commas on the

Smartmodem) so that your i.d. number will not be input until a

connection with the access number has been made. The long

distance service # might thus appear in the Dialing Directory as:

'987 6543,,,,123456'.


If your long distance service requires a different sequence --

such as inputting your account number following the number dialed

-- you can program a Function key combination for your account

number. See "The Function Key Directory" below.


Once a long distance service # has been entered into the

Directory, it will reside there permanently (until revised) and

display whenever the Directory is called up.


To dial a Directory entry # using the long distance service,

input a '+' or a '-' immediately preceding the desired entry #.


For example, to dial Directory entry #3 using the

service number listed as '+#', you would type '+3'

at the "Dial entry #:" prompt.


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Manual Dialing: 'm'


You can also use auto-dialing to call phone numbers not stored in

the Dialing Directory. From the main Dialing Directory prompt,

type 'm' . A prompt will then ask for the phone number to

be dialed. Type the phone number and press , and the

number will be dialed automatically.


As in the Dialing Directory, preceding the phone number with '+'

or '-' will route the call through one of the supplemental long

distance service numbers (if they have been stored in the Directory.)

----------------------------------------


Redialing: Alt-Q


If you have a Hayes Smartmodem, the last phone number you

have dialed can be redialed at any time by pressing Alt-Q, which

calls into effect the Redial routine.


The routine will display the time the Redial routine was started

and redial the number approximately every minute until a

connection is made.


When a connection is made, the program will sound an alarm,

prompting you to hit any key to resume communications. You can

exit from the auto-redial routine at any time before a connection

is made by hitting any key.


You can adapt the Redial routine for longer or shorter delays, or

for other modems with auto-dialing features, from within the

Default routine described below.


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Stripping and Converting Characters --


PC-TALK III provides for optional selective stripping and/or

converting of characters as they are received during

communications. This is an advanced feature.


The program default is not to strip any characters. When you

call up the Dialing Directory with Alt-D, the "Strip" column will

show "N" for each entry, indicating that no stripping is to take

place.


To specify selective stripping as part of the stored parameter

for a Directory entry, revise the entry and respond with 'y' to

the prompt "Strip/convert characters?". You will then be prompted

to enter the "strip/convert string" for that entry. This string

should be structured as follows:


Each character to be stripped or converted must be specified with

a three-digit representation of its decimal ASCII code, followed

by a slash (/), followed by a three-digit representation of the

decimal ASCII code to substitute for that character, followed by

another slash.


For example, to convert the commonly used end-of-file

character Ctrl-Z (ASCII 26) to a space (ASCII 32), the

strip/convert string would be '026/032/'. PLEASE NOTE

THAT A ZERO SHOULD PRECEDE THE ASCII NUMBER IF IT IS

LESS THAN 100.




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If you simply want to strip out a character, rather than convert

it, enter three zeros as the second part of the string:

'026/000/'.


If you want to strip or convert more than one character, continue

with more string specifications.


For example, to strip all ASCII 26's and ASCII 127's and

convert each capital A (ASCII 65) to lowercase (ASCII

97), the strip/convert string would be

'026/000/127/000/065/097'. Up to 3 characters can be

specified for stripping/converting in this manner.


You will have opportunities to correct the newly-specified string

within the revise entry routine of the Dialing Directory. (The

program pads the strip/convert string with extra slashes.) The

strip/convert string will be stored in the Dialing Directory.


When you dial a remote computer with the stripping option in

effect, the appropriate characters will be stripped and/or

converted during all incoming communications, including files

that you receive with the Receive routine. You can not have

stripping in effect when you use the XMODEM error-checking

protocol (described above).


**Applications Notes:

Please note that it is not recommended that you strip or convert

characters unless you know of a specific application or need

related to the remote computer you are calling.


It is not necessary to specify stripping of line feeds for the


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purpose of correcting the screen display, as PC-TALK does this

automatically. (Line feeds are not automatically stripped during

file receiving, however.)

----------------------------------------



Pacing Instructions --


As noted above, you can also store a Pacing instruction as part

of each Directory entry. (Pacing is discussed above in

connection with transmitting files.)


If you have stored a Pacing instruction, the pacing suffix will

automatically be added to each transmit file specification.


For example, if you had stored the pacing instruction

'p=2' for the entry you have dialed, and specify a file

to transmit simply as 'MYFILE', you will hear a

beep and the file will be re-specified as 'MYFILE=p2'.

If you press at this point, the file will be

transmitted with a 2-second pacing delay.


Continuing with the above example, if you did not want

to transmit using the Pacing option, you could backspace

to eliminate the 'p=2' portion of the file spec, press

, and transmission would proceed without Pacing

in effect.


Please note from the above examples that the Pacing instructions

stored in the Directory do not automatically transmit every file

using Pacing--they merely re-display the Transmit file specs to


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include the Pacing instruction.


**Applications and Advanced Features:

Even if you do not have an auto-dialing modem, you can use the

Communications Parameter, Echo, Message, Stripping, and Pacing

specifications to customize the program for different

applications. Store the name in the Directory and a 'dummy'

phone number such as '--' or ''. Store the rest of the

specifications. Then "dial" the entry number. Even though no

phone number will be dialed, the specifications will have been

put into effect.


You should also note that when you place a call through the

Dialing Directory, the Communications Parameters and the Echo,

Message, Stripping, and Pacing specifications will remain in

effect, even after the call is completed. You might want to set

up Directory entry #60 as a 'dummy default' entry to reset

certain specifications. You can also reset the program

parameters and defaults with the Parameter and Default routines

(Alt-P and Alt-F) described below.


**Applications Note: CompuServe and the Source

This version of PC-TALK requires that you place access numbers

for CompuServe and the Source as regular entries in the Dialing

Directory. This enables you to specify various communications

parameters and stripping instructions when calling these

networks. (You may want to place several CompuServe or Source

entries in your Directory to reflect different parameters, such

as 300-baud and 1200-baud entries.)


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**Note that some of the Source utilities, such as UPI news, may

send an ASCII 26 to mark the ends of articles or messages. If

you receive the files with these ASCII 26 characters, DOS will

later interpret them as end-of-file markers and you will not be

able to view the rest of the file, even though the information

might still be there.


If you encounter this problem, you may want to specify stripping

of ASCII 26's as part of your Source Dialing Directory entry, or

convert them to carriage returns (ASCII 13) or spaces (ASCII 32).

In such cases, your strip/convert string should be specified as

'026/000' (strip) or '026/013' (convert to carriage return) or

'026/032' (convert to space).


The feature of reprogramming the End, Ins, and Del keys for

CompuServe and the Source networks has also been eliminated from

PC-TALK III. The recommended procedure is to assign whatever

commands you regularly use either to permanent Function key

strings or to temporary Alt key strings (both of which are

described below).

----------------------------------------
















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=== Parameters and Defaults ===



Communications Parameters: Alt-P


It is not necessary that you understand communications protocols

to use PC-TALK, but you might find it helpful to read the brief

explanation of communications parameters included as Appendix A

at the end of this documentation.


Pressing Alt-P at any time while the program is running will call

up a menu which allows you to set the communications parameters

to one of four options.


The most common parameters for personal computer communications

are 300 baud, even parity, 7 data bits, and 1 stop bit (option

1). These parameters transmit text files as ASCII characters.


To transmit binary data, you should communicate with 8 data bits

(option 2). This option is also used to transmit "high-bit"

encoded files (such as Wordstar formatted text files).


Options 3 and 4 will transmit text and binary files at 1200 baud.


Option "F" of the Communications Parameters menu permits you to

reset the parameters to those specified as the program Defaults

(see below).


If you want to specify parameters other than one of the four

options, you should first press 'x' to exit to the terminal mode



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and then invoke the Default routine by pressing Alt-F.


**Applications and Advanced Features:

If either you or the remote computer is receiving unintelligible

information on the screen, you are probably using different

communications parameters. Sometimes you will be able to change

the parameters while communications are in progress, but it may

cause a break in communications, depending on the system you are

calling and the modems in use.


If you specify 8 data bits, (options 2 or 4), your modem might

not give intelligible result codes. Also, if you transmit text

files using option 2, as is required to transmit re-formattable

Wordstar files, your screen may display unintelligible

characters during transmission. The file is being transmitted

accurately, however.

---------------------------------------------



Program Defaults: Alt-F


The "defaults" of a program are those values that the program

assumes every time it is started. PC-TALK makes a number of such

assumptions, which can be changed at any time while the program

is running by pressing Alt-F.


When you press Alt-F, the screen will clear and you will see a

list of the present program defaults. They are as follows:


Baud rate 300
Parity E
Data bits 7
Stop bits 1


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These are the four communications parameters described

previously. The permissible baud rates are 75, 110, 150, 300,

600, 1200, 1800, 2400, 4800, and 9600. Parity may be E(ven),

O(dd), S(pace), M(ark), or N(one). Data bits may be 4, 5, 6, 7,

or 8. Stop bits may be 1 or 2.


Note: If you specify 8 data bits, you must specify N parity. Do

not experiment with any of these values unless you have a

specific application.


Echo N
Messages N


The default is to have both the Echo and Message functions

inactive at program startup. To have either function be active,

enter 'Y'.


Note that both functions can be controlled by the Alt-E and Alt-M

keys, regardless of how the defaults are set.


Strip #1 0
Replace #1 0
Strip #2 0
Replace #2 0
Strip #3 0
Replace #3 0


These defaults provide the opportunity to strip and/or replace

characters as they are received from the remote computer.


The "Strip #" values represent the decimal ASCII values of the characters

to be stripped or converted and the corresponding "Replace #"

values indicate the ASCII characters to replace them.



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A 0 (zero) Strip value indicates that no character is to be

stripped or converted. A 0 (zero) Replace value indicates that

the strip character is to be replaced by a null (no character).


The values listed in this menu are only the default values for

program startup. Stripping can be put into effect via the

Dialing Directory, as described in detail above. Stripping is an

advanced feature that should not be used without a specific

application in mind.


Pacing p= ''


This gives you the opportunity of specifying a default pacing

instruction, as explained previously. This default is overridden

by whatever pacing instructions may be put into effect through

the Dialing Directory. The symbol '' indicates a null entry.


Logged drive B:
Margin Width 70


Both of these default values can be controlled by the Alt-L and

Alt-W commands described previously.


Please note that all of the above defaults can be controlled

independently through program commands. The values listed in the

Default menu represent only the values the program assumes at

startup.


In contrast, the following defaults (those listed in the second

column of the Default menu) can be set only from within the

Default menu.



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Screendump file B:SCRNDUMP.PCT


This is the specification of the file that is written to when

Alt-S is pressed to activate the Screendump function.


Redial delay 20
Connect prompt CONNECT


These defaults pertain to the Alt-Q Redial function. The "Redial

delay" governs the length of time between re-dial attempts (in

seconds). The "Connect prompt" specifies the message that the

modem sends to indicate that a connection has been made.


These defaults are set to redial every minute on the Hayes

Smartmodems. They can be adapted to many other auto-dial

modems. (Consult your modem manual.)


Line 25 help Y


This default governs whether the brief prompt on line 25 of the

screen is displayed. To turn off the prompt, enter 'N'.


Foreground 7
Background 0
High inten. 15


These three values determine how characters are displayed on the

screen. If you have a color monitor, you can substitute color

values as explained in the IBM BASIC manual. Be careful that you

don't assign the same value to Foreground and Background!


Print port LPT1:
Print init. ''
Print width 80



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--- PC-TALK III User's Guide --- 49



These three values govern the use of the printer. You can

specify 'LPT2:' as an optional printer port, if that is where

your printer is connected.


The "Print init." default permits you to send characters to the

printer for alternate character fonts. The "Print width"

specifies how many columns per line the printer will handle.


For example, to print in condensed type at 132 columns

per line on the IBM Matrix Printer, enter -O (oh)

as the Print init. value and '132' as the Print width.


Comm. port COM1:
Comm. init. ,CS,DS


The first of these defaults permits you to specify 'COM2:' as the

communications port.


The second default disables checking of the "Clear to Send" and

"Data Set Ready" signals when the communications port is opened.

This default should not be changed unless you have a specific

application. Consult the IBM BASIC Manual under the OPEN "COM...

statement for details.


Modem init. ''


This provides the option of sending an initializing command to

your modem. The '' symbol indicates a null entry.


C/R subst. }


This final default specifies which character is to be used to



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--- PC-TALK III User's Guide --- 50


indicate carriage returns when defining Function key and Alt key

input strings (see below). This character may be changed at will

without altering the actual input string.


The procedure for entering new default values is simple. When

you first call up the Default menu, the cursor will be paused

next to the default for the baud rate. You can enter new values

for all the defaults or leave them unchanged as follows:


-- If you want to enter a value, type the new value and then

press .

-- If you want to leave the value unchanged, simply press .

-- If you want to enter a null (blank) value, type .


When you do not want to change any more values, type .

(Pressing the key will display a small left arrow on the

screen.)


You will then be asked whether the new values you entered are ok.

If you do not respond with 'y', you will exit the Default routine

and all of the old defaults will remain in effect.


If you indicate that the new values are ok, you will be asked

whether you want to make the changed default values permanent.

If you respond 'y', your changes will be written to a file called

PC-TALK.DEF. The new values will be put into effect, and they

will become the new default program values the next time PC-TALK

is run.


If you do not want to make the changes permanent, your new values

will be put into effect, but the old values will remain as the


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--- PC-TALK III User's Guide --- 51



defaults the next time PC-TALK is run.


**Applications and Advanced Features:

The Default routine provides you with a great degree of control

over your use of the program. The program will do some checking

for invalid default values, but you should be careful when

changing the defaults and do so only if you know of a specific

need.


If you run into trouble specifying the defaults, you can exit to

DOS and simply delete the file PC-TALK.DEF from your program

disk. PC-TALK will create a new default file if it does not

locate the PC-TALK.DEF file.


---------------------------------------------






























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--- PC-TALK III User's Guide --- 52






=== Input Strings ===



The Function Key Directory: Alt-K (or Alt-J)


One of PC-TALK's other powerful features is the Function Key

Directory, which is called up by pressing Alt-K. (To accommodate

users of the KEYNOTE program, you can also call up the Function

Key Directory with Alt-J.)


The Function Key Directory permits you to assign permanent

strings of up to 126 characters to the ten Function keys F1

through F10, and to the combinations of Alt-, Shift-, and Ctrl-

F1 through F10. A total of forty keys can thus be assigned

permanent strings, which can be used to input i.d. numbers, logon

sequences, frequently-used phrases and other text with a single

keystroke.


The information in the Function Key Directory is stored in a file

called PC-TALK.KEY and is loaded every time PC-TALK is run.


The first time the Function Key Directory is called up, you will

see that the keys F1 through F10 have no strings assigned to

them. To program a key (or to revise a previously programmed

key), press 'r' at the first prompt. You will then be asked to

specify which Function key (1 through 10) you wish to revise.

Type the appropriate number and hit .


You will then be prompted to enter the string you want to assign



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--- PC-TALK III User's Guide --- 53


to that Function key. Type the desired characters, followed by

. The directory will display the revised input for that

key. (If you make an error, press 'r' again and respecify for

that key.)


If you want to specify carriage returns as part of the input

string, input a "right curly bracket" -- the shifted key '}' just

to left of the key -- at that point in the input string.

If you want the input string to terminate with a carriage return,

enter '}' as the last character of the string.


For example, if you wanted to assign the string 'ABC

123 ' to Function key F1, you would enter

the input string as 'ABC}123}'.


The input string may be up to 126 characters in length; only the

leftmost 30 characters will be displayed in the directory.


You can "page" forward or back through the Function Key Directory

by pressing 'f' or 'b' at the initial prompt. This will permit

you to assign or revise strings for the key combinations Alt-F1

through Alt-F10, Shift-F1 through Shift-F10, and Ctrl-F1 through

Ctrl-F10.



Using the Function Key Assignments --


Once any of these forty Function keys or key combinations have

been assigned, hitting that key will send the input string

directly to the communications port (sending carriage returns in

place of '}').



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--- PC-TALK III User's Guide --- 54



Continuing with the example above, if you pressed F1 during

communications, you would send the following to the remote

computer:
ABC
123



You can specify a new string for any of the Function keys at any

time. If you want to clear the key, type as the

new input string.


The Alt-K command can be used simply to display the Function Key

Directory for reference. You can page through the Directory as

needed to confirm your key assignments. To continue with

communications, press 'x' at the initial prompt and you will

be returned to the regular terminal mode of the program. You

can then proceed by pressing any of the Function keys to send

an assigned string or proceed by typing information from the

keyboard.


IMPORTANT! DO NOT PLACE CONFIDENTIAL ID NUMBERS OR PASSWORDS IN

THE FUNCTION KEY DIRECTORY IF OTHERS WILL HAVE ACCESS TO YOUR

PROGRAM DISK. When you want to make a copy of PC-TALK for others,

do not copy the file PC-TALK.KEY, as this file may contain

confidential information.


**Applications and Advanced Features:

You can also use the Function keys to store filespecs. Pressing

the appropriate key will input the filespec in response to a

Receive, Transmit, or View file prompt.




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--- PC-TALK III User's Guide --- 55


You can include control characters (ASCII 0 through 31) as part

of the input string. The program will display these characters

as their highlighted letter equivalents (e.g., an ASCII 12 will

be displayed as a highlighted letter 'L').


You can change the character used as the carriage return

substitute from the right curly bracket to any other character

from within the Default specification routine. This carriage

return substitute only affects how the string is specified and

how it is displayed on the screen; the program always stores a

"real" carriage return (ASCII 13). Thus, you can switch back and

forth using different characters as the substitute.


A new user of the program does not need to have the PC-TALK.KEY

file on his/her disk. If the program does not locate PC-TALK.KEY

on the program disk, it will initialize and create a new blank

Function key file. The same is true for the file PC-TALK.DIR,

which contains the information used by the Dialing Directory.

---------------------------------------------


Temporary Alt Keys: Alt-1 through Alt-0


In addition to the permanent Function key combinations described

above, the ten key combinations Alt-1 through Alt-0 can be

programmed for temporary custom input while communications are in

progress.


Pressing Alt-'=' (Alt-equals) at any time during communications

will display a prompt on line 25 of the screen, asking for the

key to be programmed. Type any of the numbers 1 through 0.



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--- PC-TALK III User's Guide --- 56



You will then be prompted to enter the temporary string for that

Alt key. All keystrokes entered subsequently will input text for

that key, until you press (maximum 50 characters).


As with the Function key assignments described above, you can use

a right curly bracket '}' to include a carriage return as part of

the temporary string. Control characters will be displayed as

their highlighted letter equivalents.


When a temporary Alt key has been assigned, the program will

display the first seven characters of the programmed input on

line 25 of the screen and return to normal keyboard operation.


Once an Alt key 1 through 0 has been assigned, pressing it will

send the assigned string, just as though it had been typed from

the keyboard. The Alt keys can also be used to input filespecs.


You can change an Alt key assignment at any time by pressing Alt-

equals, followed by the number of the key to be respecified and

the new assignment.


If you want to clear a key, press Alt-equals, the number of the

key, and then type . If no Alt-key assignments

are in effect, the display on line 25 will disappear.


**NOTE the difference between these Alt key assignments and the

Function key assignments described above:


The Alt keys can be easily reprogrammed during communications and

are displayed on line 25 of the screen. This makes them con-

venient for holding temporary input strings needed for quick


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--- PC-TALK III User's Guide --- 57



reference. However, the Alt-key assignments are not saved when

the program is terminated.


The Function key assignments, on the other hand, are stored

permanently on disk and reloaded each time PC-TALK is run. This

makes them convenient for storing id numbers and logon sequences.

However, you cannot continue with communications while you are

reassigning the Function keys.

---------------------------------------------









































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--- PC-TALK III User's Guide --- 58






=== Miscellaneous Features and Commands ===



Elapsed Time: Alt-Z


At any time during program operation, you can display the elapsed

time for the current call by typing Alt-Z. For updated time, hit

Alt-Z again. (The elapsed time is reset whenever a new call is

made.)



Exit: Alt-X


Pressing Alt-X at any time will give you the option of

terminating the program and returning to DOS.



Sending a Break Signal: Ctrl-End


Various remote computer systems use different signals to effect a

break during communications. For example, the break signal for

CompuServe is a Control-C; the Source Break signal is a Control-

P. Any key sequence (including all control key combinations) may

be sent via the keyboard. Some break sequences may also be

programmed via the Function Key Directory.


Some systems require a special "sustained" Break signal. This

signal can be sent by hitting the Ctrl and the End keys

simultaneously. You will have to experiment, or consult your

remote system's documentation to determine the correct Break

signal to use.


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--- PC-TALK III User's Guide --- 59




CAUTION: do not attempt to use the combination of the Ctrl key

and the ScrollLock/Break key as this may terminate PC-TALK.



Command Summary: Home key


An on-screen summary of all the PC-TALK program commands

described above can be displayed at any time by hitting the Home

key.


Toggle Commands:


The following keys toggle on/off their respective functions and

operate at any time while the program is running:


Alt-T Transmit Alt-E Echo

Alt-R Receive Alt-M Messages

Alt-V View Ctrl-PtrSc Printout


----------------------------------------























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--- PC-TALK III User's Guide --- 60






=== More Applications and Advanced Features ===



Even though this section is described as "advanced," the

following information should be of interest to all users of the

program.



XON/XOFF: Alt-O


PC-TALK supports the sending of XON/XOFF signals to the remote

computer in the event of a communications buffer overflow (see

below), and will trap for XON/XOFF signals sent by the remote

computer during transmission of files. The default XON signal is

ASCII 17; the default XOFF signal is ASCII 19.


If the remote computer sends an XOFF signal during transmission

of a file, the symbol "<>" will be displayed highlighted on

the screen until the remote computer sends an "XON" signal, at

which time transmission will resume automatically. If transmis-

sion has been halted, it may be resumed manually by typing Alt-O

(the letter 'oh') at the keyboard.



Communications Errors: <<>> and <>


PC-TALK will indicate certain types of errors if they occur

during communications. If there is an ambient signal on the

line, the program will display the symbol '<<>>' in high

intensity. Communications will not be interrupted in most cases,



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--- PC-TALK III User's Guide --- 61


but this symbol should put you on notice that you are sending or

receiving corrupted data. On a very noisy line, you may see the

symbol repeatedly. You should disconnect and try for a better

connection.


With some modems, including the Hayes Smartmodems, you may

see the <<>> symbol when communications are first opened. This

should not be a cause for concern, provided you do not see the

symbol once communications are in progress.


PC-TALK opens a communications buffer for receiving data through

the communications port. In most cases, the program should be

able to process data as fast as it is received. If the

communications buffer does fill faster than the program can

handle the incoming data, you will see the symbol <> on

the screen. The program will then try to recover, by sending an

XOFF signal to the remote computer, processing the contents of

the buffer, and then sending an XON signal.


Two situations should be noted which may cause an overflow

condition. If you are running the uncompiled BASIC version of

the program at 1200 baud, you may experience an overflow

condition if you are making use of the character stripping

options, or if the remote computer does not support XON/XOFF.


If you are trying to perform simultaneous printout at 1200 baud,

your printer will probably not be able to keep up and eventually

the buffer will overflow, even with the .EXE version of the

program. PC-TALK will attempt to recover by turning off the

print feature.


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--- PC-TALK III User's Guide --- 62






=== PC-TALK III File Information ===



PC-TALK III is supplied with the following files:


PC-TALK.BAS -- The BASIC source code for the program. It will

run on a 64K system using DOS 1.00 or 1.10 and BASIC 1.10.


PC-TALK.EXE -- The compiled BASIC version of the program. It

will run under DOS 1.00, 1.10, or DOS 2.00 on a system with 128K

or more of memory.


PC-TALK.DOC -- The text file containing this documentation.


TALK64.BAT -- A batch file that runs the 64K version. The file

contains the single command 'BASIC PC-TALK/C:1024'. This

sets up a 1024-byte communications buffer.


TALK128.BAT -- A batch file that runs the 128K version. It

contains the single command 'PC-TALK'. The .EXE version can, of

course, be run directly from DOS with the command 'PC-TALK'

.


PRINTDOC.BAT -- A batch file with a series of prompts to print

the documentation file from DOS.


COPYTALK.BAT -- A batch file to aid in making copies of PC-TALK

for other users. It will not copy your personal .DIR, .KEY, and .DEF

support files.





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--- PC-TALK III User's Guide --- 63


The first time PC-TALK III is run, the program looks for three support

files. If it does not find them, these three files will be created on

the program disk:


PC-TALK.DIR -- The file that stores Dialing Directory information.

PC-TALK.KEY -- The file that stores Function Key information.

PC-TALK.DEF -- The file that stores Default Menu information.

----------------------------------------



Programming Information --


One additional file is supplied on the program disk: PCTKREM.MRG.

This is a BASIC file saved in ASCII format that contains REMark

statements. It can be MERGED into PC-TALK.BAS to improve the

readability of the program. However, once merged, PC-TALK.BAS

will no longer run on a system with 64K of memory.


PC-TALK.EXE can be compiled directly from PC-TALK.BAS, as all

timing functions are handled independently through the BASIC

SOUND and TIME$ functions.


Once PC-TALK.BAS has been saved in ASCII format, it can be

compiled using the IBM BASIC Compiler with the following commands:


BASCOM PC-TALK.BAS /E/O/S/C:4096
LINK PC-TALK+IBMCOM


The '4096' argument determines the size of the communications

buffer and can be increased if you have sufficient memory. For

all but the most demanding applications, however, the 4096-byte

buffer should be more than sufficient.



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--- PC-TALK III User's Guide --- 64



---------------------------------------------



Copying PC-TALK --


You are encouraged to make copies of PC-TALK III and distribute

them to other users, within the terms of the limited license set

forth below. A special batch file has been provided for this

purpose.


To copy PC-TALK III, insert the program disk in drive A. From

the DOS A> prompt, type 'COPYTALK' and follow the

prompts. If you do copy PC-TALK for other users, please be sure

to provide them with the PC-TALK.DOC and PRINTDOC.BAT files.

---------------------------------------------



Modifying PC-TALK --


Please note that this version of PC-TALK makes use of virtually

all the memory available on a 64K system when running the

interpreter BASIC version (PC-TALK.BAS). Adding any modifica-

tions will exceed the memory capacity for 64K machines.


This version of PC-TALK has incorporated the suggestions of many

users who made modifications to earlier versions. Some of these

earlier modifications were posted on bulletin boards and became,

in effect, "standard" modifications to the earlier program.


There are still many more useful modifications which could be

made, and we would like to encourage this grassroots improvement

process. The only "dangers" are of different people writing


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--- PC-TALK III User's Guide --- 65



modifications which overlap or are inconsistent, and, of course,

people unwittingly writing bugs into the program.


You are free to modify PC-TALK as you wish to suit your personal

needs. One of the goals in creating PC-TALK was to produce a

program in easily modifiable BASIC. We do request, however, that

you do not distribute PC-TALK in modified form. The reason for

this is that when people have problems or questions, they

inevitably contact us, and we have no way of knowing what

modifications may have been made.


If you do come up with useful modifications, please keep them as

separate MERGE files which can be incorporated into PC-TALK.BAS

at the user's option.


To facilitate this process of creating mergeable mods, we would

appreciate your sending us copies of your mods (on disk, if they

are substantial). In certain cases, we may want to endorse

certain mods and "officially" reserve expansion areas for them.

Program lines from 10000 up have specifically been reserved for

this purpose.


Please understand that our reason for suggesting that we might

"approve" certain modifications is not in any way meant to

inhibit your insights or creativity. To the contrary, we're

greatly appreciative of the improvements which have been made to

the program so far, and we would merely like to make it easier

for more people to share in future improvements.

---------------------------------------------



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--- PC-TALK III User's Guide --- 66




Thank You!


While on the subject on user mods, I would like to express my

thanks to Larry Jordan, Rich Schinnell, Wes Merchant, Don

Winthrow, and the Capital PC Users Group for their many

suggestions, contributions, and continued support.


John O'Boyle of United Technologies has been particularly helpful

and encouraging in developing version III and in championing the

Freeware concept. Thanks also to Phil Ryals of Bank of America

and to Joe Doran of GCA Corporation for their programming insights.


Special thanks to Jeremy Joan Hewes for being my trusty cohort

and dear friend from the very beginning and to Larry Magid and

Stu Schwartz for their tireless beta testing and for never being

satisfied. And thanks to Patricia Navone and Susan Stone for

their loyal and excellent work.


Finally, thank you to the entire PC Community for your many words

of encouragement and your financial support. PC-TALK and

Freeware started as an experiment. It seems to have worked

beyond what anyone suspected. I hope that you find this version

of PC-TALK to be more useful and just as friendly as the prior

versions, and that we continue to find ways to share our

adventures in computing.


-- Andrew Fluegelman

---------------------------------------------





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--- PC-TALK III User's Guide --- 67




tm
======================== F R E E W A R E =======================

User-Supported Software

If you are using this program and finding it of value,
your contribution ($35 suggested) will be appreciated.

=== F r e e w a r e ===
The Headlands Press, Inc.
Post Office Box 862
Tiburon, CA 94920

Regardless of whether you make a contribution,
you are encouraged to copy and share this program.

---------------------------------------------


FREEWARE user-supported software is an experiment in distributing
computer programs, based on three principles:

First, that the value and utility of software is best assessed by
the user on his/her own system. Only after using a program can
one really determine whether it serves personal applications,
needs, and tastes.

Second, that the creation of independent personal computer
software can and should be supported by the computing community.

Finally, that copying and networking of programs should be
encouraged, rather than restricted. The ease with which software
can be distributed outside traditional commercial channels
reflects the strength, rather than the weakness, of electronic
information.


The user-supported concept:

Anyone may request a copy of a user-supported program by sending
a blank, formatted disk to the author of the program. An
addressed, postage-paid return mailer must accompany the disk (no
exceptions, please).

A copy of the program, with documentation, will be sent by return
mail. The program carries a notice suggesting a contribution to
the program's author. Making a contribution is completely
voluntary on the part of the user.

Regardless of whether a contribution is made, the user is
encouraged to copy and share the program with others. Payment for
use is discretionary on the part of each subsequent user.



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--- PC-TALK III User's Guide --- 68




Will the user-supported concept really work?

Up to now, distribution of software has relied either on
restricting access (and charging for the cost of doing so), or
anonymously casting programs into the public domain. The user-
supported concept is a way for the computing community to support
and encourage creative work outside the traditional marketplace.

This is an experiment in economics more than altruism. Free
distribution of software and voluntary payment for its use
eliminates the need for money to be spent on marketing,
advertising, and copy protection schemes. Users can obtain
quality software at reduced cost, while still supporting program
authors. And the most useful programs survive, based purely on
their usefulness.


Please join the experiment.

FREEWARE is the trademark of The Headlands Press for its user-
supported software, but we invite all software authors to
participate in this distribution concept.

We would like to publish a FREEWARE CATALOG of user-supported
software by program authors who are willing to make their work
available on a free, non-restricted basis. If you would like your
program listed, please send a description of the program
(including system requirements) and the address to which requests
for copies should be sent. Fulfilling requests and suggesting
contributions are the sole responsibility of each program author.
Listings in the catalog are free.

We welcome your comments about the user-supported concept.
Thank you for your support.

Andrew Fluegelman
Freeware

----------------------------------------------------
NOTICE - A limited license is granted to all users of this program,
to make copies of this program and distribute them to other
users, on the following conditions:

1. The program is not to be distributed to others in
modified form.
2. No fee (or other consideration) is to be charged for copying
or distributing the program without an express written
agreement with The Headlands Press, Inc.
3. The notice displayed at program start-up is not to be
bypassed, altered, or removed.

Copyright (c) 1983 The Headlands Press, Inc.
----------------------------------------------------


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--- PC-TALK III User's Guide --- 69




Appendix A: A Brief Explanation of Communications Parameters


The communications "parameters" are simply values that specify
how data is to be sent. The "baud rate" is the speed of
transmission--300 baud means 300 bits per second. Since it
usually takes 10 bits to transmit one character, 300 baud is a
transmission rate of approximately 30 characters per second. A
baud rate of 1200 is four times as fast--about 120 characters per
second. (Your modem must be able to support the baud rate you
select.)


As mentioned, it usually takes a stream of 10 bits to transmit
one ASCII character. One of these 10 bits can be designated as a
"parity" bit. The value of this bit can be set so that, when
added to the other data bits (described below), the sum of the
data and parity bits is either even, odd, always one ("mark
parity") or always zero ("space parity"). If you have chosen to
communicate with 8 data bits rather than 7 data bits (see next
paragraph), there is no "room" for a parity bit, and so you must
specify "no" parity.


You can choose to communicate with various numbers of data bits.
The most common values are 7 data bits, which allow you to send
any of the 127 standard ASCII characters, or 8 data bits, which
allow you to send an extended ASCII set of 255 characters.


For every character transmitted, the communications program sends
1 "start" bit. You have no option to vary this number. However,
you can specify how many "stop" bits are to be sent. There must
be at least 1 stop bit, and this is the most common value.





















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--- PC-TALK III User's Guide --- 70





Appendix B: A Brief Description of the XMODEM Protocol


Once the protocol is put into effect ("Holding for Start..."),
the transmitter waits for the receiver to send an NAK character
(ASCII 21). Meanwhile, the receiver sends NAK signals every ten
seconds. Once the transmitter detects an NAK, it starts to send
the file in sections of 128 bytes.


Actually, more than 128 bytes are sent for each block. At the
beginning of the block is an SOH character (ASCII 01), followed
by the ASCII character representing the block number, followed by
the ASCII character of the "one's complement" of the block
number. Then the 128 bytes of the file are sent. Finally, the
block concludes with an ASCII character representing the sum of
the ASCII values of the 128 bytes sent (the "checksum"
character).


The receiver checks the block to verify that everything is in
order. First it makes sure that the block started with an SOH.
Then it makes sure that the block number is correct. Then it
performs its own calculations on the 128 data bytes and compares
its own checksum with the one received from the transmitter.


If everything is in order, the receiver sends an ACK character
(ASCII 06) to the transmitter, indicating that the next block is
to be sent. If the receiver can't verify, it sends an NAK,
requesting that the block be sent again. This continues, block
by block, until the entire file has been sent and verified.


At the end of the file, the transmitter sends an EOT character
(ASCII 04). The receiver acknowledges the EOT with an ACK, and
the transfer terminates.

















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=== Finished printing the PC-TALK III User's Guide ===



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