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1995-03-21
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1,771 lines
Chuck Forsberg
User Manual for
ZCOMM
Universal Line Printer Edition
ZCOMM Communications Software
Featuring
TurboLearn(TM) Script Writer,
Cybernetic Data Recovery(TM), Error Containment(TM),
and
OverThruster(TM)
User Supported Communications Software Tools
User Manual for
ZCOMM
Universal Line Printer Edition
Copyright 1994 Omen Technology Inc
All Rights Reserved
Omen Technology Incorporated
The High Reliability Software
Box 4681 Portland Oregon 97208
VOICE: 503-621-3406 :VOICE
TeleGodzilla BBS: 621-3746
Compuserve:70007,2304 GEnie:CAF BIX:cforsberg
caf@omen.com
Copyright 1984, 1994 Omen Technology INC All Rights Reserved
(C) 1994 Omen Tech Inc Chapter 0
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 2
1. INTRODUCTION
ZCOMM
Industrial Stength Communications Shareware(TM)
#---------------------------------------------------------------------#
# Professional-YAM Copyright 1991 Omen Technology INC #**
# #**
# ZMODEM RECEIVE #**
# #**
# File pcmagc.dmp 1 of 5 #**
# #**
# Current 43520 of 43520 Total 43520 of 999879 #**
# #**
# This ################################################## #**
# 0------------------------50------------------------100% #**
# Total ##- #**
# State START FILENAME COMPARE DATA CORRECTING FINISH WAIT #**
# Throughput 8704 Retries 0 Time left 2 min #**
# Connect ET 13:09 Time 13:18 Modem status #**
# #**
# #**
# Packet LEN 43520 TRANSPORT COMPRESSED DATA BINARY #**
# Subpkt LEN 512 Window SIZ #**
# ALT-F Cancel File ALT-B Cancel Batch #**
# #**
#---------------------------------------------------------------------#**
************************************************************************
38kbps ZMODEM-90(TM) file download from a Unix system. ZMODEM-90(TM)
compression yields 87kbps effective speed on the[1] PC Magazine
Compressible File Benchmark. When PC Magazine tested communications
programs with ZMODEM, the fastest transfer they remember seeing was a
wimpy 38.58 kilobits/sec from Hyper/Access/5, not the 87 kilobits/sec
shown above. That's what happens when you don't look at the manual!
ZCOMM helps collect, control, and transmit information with a minimum
of time, hassle, and expense. Concise commands and unobtrusive
displays facilitate telecommunications instead of distracting.
When it comes to file transfers, just remember who wrote YMODEM and
ZMODEM. Two decades of telecommunications knowledge are distilled in
ZCOMM.
__________
1. Page 159, April 30 1991 PC Magazine. File obtained from PC
Magazine with permission.
(C) 1994 Omen Tech Inc Chapter 1 Introduction
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 3
State of the Art File Transfers
"ZMODEM is the overall winner"
-BYTE Magazine, Feb 1989
"Professional-YAM showed the fastest file transfer times"
-PC Magazine, 1991
Two decades of communications experience are distilled in ZCOMM.
ZCOMM transfers files quickly and surely under real world conditions,
not just across tabletops. Unsolicited customer testimonials
chronicle accurate file transfers under conditions that crash other
programs, thanks to Omen Technology's Cybernetic Data Recovery(TM)
logic enhancements and rigorous stress testing.
How often has your modem disconnected when you were within a few bytes
of finishing a long, expensive file transfer? With ZMODEM-90(TM) you
can resume the transfer from where you were cut off, without wasted
time or extra phone charges. If the transfer aborted because you ran
out of disk space, ZMODEM can recover from that too!
ZMODEM transfers files and commands with a user friendly interface.
Unlike traditional protocols, only one command or menu choice is
needed to transfer files or download commands.
"Pro-YAM's AutoDownload feature for ZMODEM (and KERMIT) has got me
completely addicted."
ZMODEM protects your data with a 32 bit CRC, five orders of magnitude
more accurate than the CRC-16 used by other protocols, and billions of
times more sensitive than XMODEM checksum. Unlike "me too" protocols
developed to compete with ZMODEM, all ZMODEM messages are protected
with CRC.
ZMODEM provides high throughput and full integrity with timesharing
systems, high speed modems, and packet switched networks. Unlike
other protocols, ZMODEM's does not compromise reliability to get high
speed.
Omen Technology's ZMODEM-90(TM) extensions accelerate transfers and
enhance flexibility.
Pro-YAM's ZMODEM compression provides spectacular throughput increases
on suitable files, significantly faster than other protocols tested
with the PC Magazine Compressible Test File.
Other ZMODEM features include text file translation, selective
transfer of modified files, and remote file maintenance. A single
command can update an entire directory tree, creating new
subdirectories as necessary.
(C) 1994 Omen Tech Inc Chapter 1 Introduction
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 4
Security authentication* disables Trojan Horse attacks.
ZMODEM supports world wide operations by preserving the exact file
contents and modification date, unaffected by crossing time zones.
Omen Technology provides complimentary Unix and VAX/VMS ZMODEM servers
in source and binary formats.
"Here's the simple fact. Zmodem is the state-of-the-art protocol for
microcomputers. It's the protocol of choice. Forget the old dogs.
It's fast and bullet-proof."
-John C. Dvorak, INSIDE TRACK, PC Magazine June 1989
"without doubt the number one protocol"
-Boardwatch Magazine January 1990
Competitors hype their undocumented proprietary protocols; experienced
BBS operators know ZMODEM is the only high performance protocol that
survives on the streets. ZMODEM's convenience, speed and reliability
have made it the protocol of choice for bulletin boards, BIX, GEnie,
Portal, Delphi, Unison, and other information utilities.
XMODEM: Lingua Franca for Old Programs
ZCOMM supports Ward Christensen's XMODEM protocol with Cybernetic Data
Recovery(TM) and automatic file name generation. Omen Technology's
exclusive Cybernetic Data Recovery transfers files under conditions
that crash other programs.
+ XMODEM CRC-16 is more accurate than simple checksum. But even with
CRC-16, an error of just two bits can corrupt data sent with
XMODEM. Cybernetic Data Recovery catches and corrects many errors
that confound other programs.
+ True YMODEM(TM) batch file transfers preserve the exact file name,
file length and creation date.
+ XMODEM-1k and YMODEM-1k 1024 byte packets increase XMODEM
throughput.
Kermit: Rx for Brain Damage
Kermit transfers ASCII and binary files with IBM, CDC, Cray, ICL,
Harris, Honeywell, Pr1me, Tandem, Univac and other traditional
mainframes that do not support XMODEM.
While not as fast as ZMODEM, Kermit is more reliable than XMODEM.
ZCOMM's 16 bit Kermit CRC is thousands of times more accurate than
other programs' 6 bit checksum.
(C) 1994 Omen Tech Inc Chapter 1 Introduction
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 5
+ Convenient Kermit AutoDownload deciphers the sending program's
Kermit dialect, saving keystrokes and frustration. (Dialect
incompatibilities often confound Kermit users.)
+ Long Packet Kermit speeds file transfers with IBM, CDC, and Cray
mainframe systems. Sliding Windows are also supported. Kermit
Server Access functions support low cost networking.
Swiss Army Knife for Protocols
+ Extended Quick-B streaming protocol slashes CompuServe download
costs up to 60 per cent or more.
+ OverThruster(TM) accelerator speeds XMODEM and YMODEM downloads
+ ZCOMM supports bulletin boards and traditional programs with
Telink/FIDO, MODEM7 batch, WXMODEM (Windowed XMODEM), and SEAlink
file transfer protocols.
Data Capture
ZCOMM's Full-Time Capture Buffer(TM) saves scrolled data other
programs lose. You can scroll, page, and string search to cut and
paste captured information.
Omen's Error Containment(TM) technology minimizes errors caused by
line hits and their effects on automatic scripts.
ZCOMM captures text with many choices of parity bit and control
character editing. ZCOMM can capture binary data without protocols.
ZCOMM does not limit the length of captured files.
Controlling Information
ZCOMM's Full-Time Capture Buffer(TM) lets you flip back and forth or
search, scanning two hundred messages from bulletin boards in a couple
of minutes. (It has to be seen to be believed.) To compose a reply,
call your favorite editor (the one you've already learned!) as a
subroutine without losing your place.
ZCOMM's high speed screen driver- makes life pleasant:
+ Easy on the eyes: ZCOMM supports No Flicker displays, up to 450 per
cent faster than DOS
+ VT220, VT102, VT100, Wyse, TTY 5425, ANSI, Z19, VT52, TI 940, IBM
3101, Televideo 9xx, and ADM3a emulation.
(C) 1994 Omen Tech Inc Chapter 1 Introduction
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 6
+ Supports VTxxx and Wyse "Printer Controller Mode".
+ Supports 132 columns and advanced displays (114x60, etc.)
+ VT100 character graphics and keyboard mapping support "visual"
programs. Unlike most "VT100" emulators, ZCOMM correctly displays
EDT, All-In-1, SCO setcolor, and DEC Store on an XT even at 19200
baud.
+ Hardcopy Terminal Emulation previews printer output.
+ Visual (silent) bell preserves domestic tranquillity
+ Settable number of lines and columns, border color, default colors,
autowrap, keyboard mapping enable.
Full pathnames, directories, and wildcards support file transfers and
utility commands.
ZCOMM can search files for lines matching a string, insensitive to
case.
Transmitting Information
+ Dual stack Command Recall saves your keyboarded host commands in a
history file for search, recall, editing, and reentry.
+ Convenient Split Screen option- allows responsive local editing of
input lines before transmission.
+ A rich palette of editing and timing modes permit file and message
upload, even to fussy microcomputer Bulletin Boards.
+ Remote access for file transfers and DOS program execution with baud
rate detection and three passworded security levels.
+ Outcall Queue intersperses scheduled outgoing calls with incoming
messages on one modem line.
1.1 Other Features
Interrupt driven modem input allows High speed operation with file
transfer and conversational terminal operation at 19200 bps and above.
ZCOMM fully exploits advanced features of the new UART chips for best
operation at high speeds.
A real-time status line displays column, row, time, elapsed time,
transmission speed, and other important information.
Soft keys provide convenient execution of common commands.
(C) 1994 Omen Tech Inc Chapter 1 Introduction
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 7
ZCOMM is written in C for performance, portability and
maintainability. ZCOMM loads quickly from a moderately sized
executable file with no cumbersome overlays.
(C) 1994 Omen Tech Inc Chapter 1 Registration
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 8
2. ZCOMM REGISTRATION
ZCOMM is a user supported program developed and supported by Chuck
Forsberg. ZCOMM is not and never has been public domain.
Registration buys you:
+ Your own unique ZCOMM Serial Number Password (ZSNP). Your ZSNP
may be applied to copies of ZCOMM to be run on a single machine.
+ Serialized of ZCOMM deactivates the registration request
display and the pause afterwards.
+ Serialization activates the egrep, egrepm, expand, split,
and ss commands and the outcall queue. Features denoted
with ** are available in serialized copies of ZCOMM.
+ Serialization more than doubles the circular buffer size.
+ A software disk with the current version of ZCOMM, the putsnp
program to serialize your copy of ZCOMM with your ZSNP, and the
tree structured "flash-up" help processor and help file included
in ZCOMMHLP.ARC.
+ The complete Professional-YAM User Manual, more than 200 Typeset
pages, with many chapters not included here, ready for insertion
into a PC size binder.
+ The Pro-YAM Crib Sheet.
+ A ZCOMM registration is worth $40.00 when upgrading to
Professional-YAM. The $99.00 upgrade includes the Pro-YAM
software disks and license. You will already have the manual
from your ZCOMM registration package.
+ A warm fuzzy feeling arising from the knowledge you have
supported the advancement of ZMODEM.
REGISTRATION DETAILS:
+ Basic registration (ZSNP, disk, manual pages): $40.00
+ Optional Custom Binder: $10.00
+ Optional 3.5 inch diskette: $5.00
+ Domestic/Canada Surface Shipping: Free with prepaid orders
+ International Air Mail (most countries): $15.00[1]
(C) 1994 Omen Tech Inc Chapter 2 Registration
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 9
+ Optional Domestic UPS Second Day AIR: $5.00
+ Credit Card/C.O.D. S&H: $5.00
Don't bother scrounging for an envelope, use the INSTANT MAILER
included in this archive!
2.1 Legal Necessities
ZCOMM may not be modified, patched, hacked, disassembled, decompiled,
or otherwise reverse engineered, or sold, without prior written
permission by Omen Technology Inc. This prohibition applies to any
theft of the intellectual property and trade secrets contained in
ZCOMM by decompilation, disassembly, or any other form of reverse
engineering including but not limited to profiling, tracing, data
analysis, or monitoring the operation of ZCOMM.
The only legitimate way to disable the opening advertisement in ZCOMM
is to insert an authorized SNP obtained from Omen Technology into
ZCOMM with the putsnp program. Any other suppression or modification
of the opening screen is illegal, unethical, and prohibited.
Distribution of programs and/or instructions on how to modify, patch,
disassemble, decompile, or otherwise reverse engineer ZCOMM without
prior written permission by Omen Technology Inc is a theft of services
and a violation of federal copyright law, and will be referred to the
FBI for investigation and prosecution under federal conspiracy
statutes. Applicable RICO law provides for treble damages and
recovery of attorney's fees.
Distribution of ZCOMM in any medium without this documentation file
constitutes an unauthorized modification.
Students may use unregistered copies of ZCOMM in the discharge of
assigned coursework for the duration of the course without obligation
to register. Otherwise, individuals may use ZCOMM with only a moral
obligation to register their copy with Omen Technology once they find
it useful. You may distribute the unmodified ZCOMM*.ARC archive
files[2] to as many as you wish, or post them on bulletin boards, etc.
Businesses must register their copies of ZCOMM.
______________________________________________________________________
1. $25.00 to Australia etc. if binder included due to higher cost.
2. The archives may be converted to other storage or archive formats,
including "zipping", provided no files are modified or removed.
(C) 1994 Omen Tech Inc Chapter 2 Registration
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 10
3. ZCOMM's Big Brother
ZCOMM is the Little Brother of Professional-YAM. As powerful as ZCOMM
is, more powerful than other user supported software, it pales beside
Omen Technology's commercial Professional-YAM software.
Pro-YAM's TurboDial(TM) script language provides state of the art real
time pattern recognition, "regular expiression" string parsing, script
development aids, script encryption, queue management, extensive
logging facilities, and finely tuned security control unmatched in the
industry.
Fortune 500 corporations use these exclusive features to support large
PC based telecommunications projects involving attended and unattended
operation.
Specialized utility commands allow Pro-YAM and a PC or DG/One portable
to replace data line monitors in many applications. Pro-YAM supports
Echoplex uploads and high speed data dumps in addition to the uniquely
accurate and robust XMODEM, YMODEM, ZMODEM, and Kermit protocol
transfers shared with ZCOMM. Pro-YAM has many powerful utility
commands that earn it the sobriquet Integrated Communications Tools.
Pro-YAM is available with the Tymnet X.PC link level protocol for
multiple, concurrent data transfers.
Omen Technology also markets highly compatible Unix and Xenix flavors
of Pro-YAM.
Omen Technology's Demand Upgrade(TM) technology and small company
responsiveness meet the support needs of a growing base of demanding
customers.
Professional-YAM is a superset of ZCOMM; applications and scripts
developed on ZCOMM will operate with Pro-YAM.
This ZCOMM manual omits descriptions of many Pro-YAM features not
included in ZCOMM. The special symbol * denotes Pro-YAM features not
included in ZCOMM.
Pro-YAM features not included in ZCOMM include X.PC, encryption,
CryptoScript(TM) capability, Password Guardian(TM), logs, the ap, apd,
fget, fput, kbdmon, link, on, portx, purgek, quit, restime, restrict,
timestamp, and trs commands, and certain vertical application and
security related features. (Newer versions of ZCOMM include the
logging facility.)
In some places you will see references to a fake Chapter 99. Pro-YAM
manual chapters not included in this document are designated by
Chapter 99.
(C) 1994 Omen Tech Inc Chapter 3 ZCOMM
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 11
ZCOMM registration can be upgraded to Pro-YAM as described in the
previous chapter.
(C) 1994 Omen Tech Inc Chapter 3 Flavors of Professional-YAM
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 12
4. FLAVORS OF Professional-YAM
4.1 IBM PC Family and Clones
YAM and ZCOMM run under PC-DOS and compatible operating systems using
PC compatible 8250 family serial ports. They exploit the new Intel
82510 and National NS16550AN serial interface integrated circuits for
improved high speed operation, especially with memory resident
software and extended memory ramdisks.
YAMXPC supports the Tymnet X.PC packet protocol. This version uses
the Tymnet Packet Driver and will not initialize unless the packet
driver has been loaded. The X.PC version lacks the bdump and link
commands. The !~ command does not allow DOS subprograms to access the
serial line with the DOS ctty command.
YAM is also available for OS/2 protected mode.
4.2 Xenix/Unix
Pro-YAM for 32 bit Unix systems supports a number of advanced
features, including X windows[1] large memory, recursive wild card
expansions and ZMODEM transfers with RLE or LZW data compression.
Unix and Xenix flavors of Pro-YAM reflect the deep fundamental
differences between single tasking PC-DOS and Xenix. Notable
differences are in keyboard handling, screen emulation, and real-time
aspects. Properly written TurboDial(TM) Scripts may be used with any
flavor of Pro-YAM. Omen Technology provides binary executables for
SCO System V Xenix (286 and 386) and Interactive Systems 386/ix. The
386/ix flavor supports Microport SYS V/386 and similar systems.
Please contact Omen Technology for reasonably priced source code for
other versions of Unix.
4.3 VAX/VMS
VAX/VMS Professional-YAM supports dial out applications with
functionality similar to Unix flavors. Popular VMS record types are
supported.
__________
1. Under xterm(1).
(C) 1994 Omen Tech Inc Chapter 4 Flavors of Professional-YAM
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 13
4.4 ZCOMM
ZCOMM is a shareware subset of Pro-YAM available for PC-DOS. It lacks
the ap, apd, fget, fput, link, kbdmon, obey, on, quit, purgek,
restime, restrict, timestamp, and trs commands. Arbitrary variable
names and security features are not supported. Certain commands and
features are available only in registered copies. The special symbol
* denotes features not included in ZCOMM. Features denoted with **
are available in registered copies of ZCOMM.
Some ZCOMM users choose to upgrade to Professional-YAM. Omen's ZCOMM
to Pro-YAM upgrade policy protects your investment in ZCOMM
registration. The ZCOMM to Pro-YAM upgrade consists of a Pro-YAM
serial number and diskette set. The $99.00 price is the same as the
difference between Pro-YAM purchase and ZCOMM registration.
(C) 1994 Omen Tech Inc Chapter 4 Design Philosophy
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 14
5. DESIGN PHILOSOPHY
ZCOMM is a Communications Tool. Once learned, ZCOMM's command
interface is more powerful, faster, and less cumbersome than a menu
interface. Indeed, menus comprehensive enough to describe all the
nuances of ZCOMM's capabilities would take up more memory than most
microcomputers can afford. In addition, remote operation of ZCOMM
would be excruciatingly slow due to transmission delays displaying the
appropriate menu pages.
ZCOMM's look and feel has been influenced by the MODEM series of
programs, the Unix(TM) Operating System, the Berkeley Editor (vi),
CP/M(TM), PC-DOS, and ANSI standards.
Function keys F1 and F2 have been assigned with a logical grouping.
Wherever meaningful, F1 exits from a function, and F2 enters the
logical "next" function. From the command prompt, F2 enters the term
function, and from there another F2 enters the review function. Once
in the review function (assuming it was called from the term
function), F1 exits back to the term function, from where another F1
exits to the command prompt.
Another ethic guiding ZCOMM's design is respect for the user's
information. The user's data is, after all, precisely what a modem
program is all about. Status information is limited to one CRT line
to allow maximum screen size for data. Fancy display modes such as
reverse video are used sparingly to avoid distracting from the user's
work.
If you seek a video arcade modem game, ZCOMM will disappoint you.
5.1 Circular Buffer
The circular buffer remotely resembles the linear "capture buffer"
used by other modem programs. Many ZCOMM commands involve the
circular buffer, including the t, f, wait, ki, kill, w, review, and
close commands.
The term function uses the circular buffer as a first in, first out
(FIFO) buffer for data arriving from the remote. The circular
organization of this buffer makes the most recent data always
available for review and arbitrary writing to disk files.
When the circular buffer has been filled and the XOFF character sent
to the remote, ZCOMM writes the contents of the circular buffer to the
capture file if a capture file has been opened. ZCOMM then checks
whether any characters remain to be written to the printer. When both
of these checks are satisfied, ZCOMM then sends an XON character to
the remote to resume the transmission of data.
Keyboarding ALT-W or enabling j term option writes the contents of the
(C) 1994 Omen Tech Inc Chapter 5 Circular Buffer
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 15
circular buffer to the capture file without waiting for the circular
buffer to fill up first.
The large storage capacity of the circular buffer may be used to
review the most recent data captured from the remote. The review
commands lets you page back and forth through the data captured from
the remote. Forward and backward string searches make it easy to
locate important text. The review commands also let you save segments
of the circular buffer to disk (cut and paste). Scripts can search
and mark text captured from the remote with the full power of regular
expression pattern matching. These commands will be explained later.
(C) 1994 Omen Tech Inc Chapter 5 Rosetta Stone
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 16
6. ROSETTA STONE
Alphanumeric An alphanumeric character is either a letter or a decimal
digit 0 to 9.
Baud A baud is a signaling unit conveying one or more bits of
information. Baudrate is commonly (and usually incorrectly)
interchanged with bits per second.
BPS is an abbreviation for "bits per second", a measure of
transmission speed. ASCII Asynchronous transmission generally
uses 10 bits to transmit each character, so the speed in
characters per second is one tenth the speed measured in bits per
second.
Capture The term function captures data from the remote into the
circular buffer. This data may be paged back and forth with the
review function, or written to a disk file.
Character Escape is a sequence of characters initiated by a backslash
character used to represent a control character or programmable
string using printable characters. Character escapes are
described in Chapter 26.
CPMEOF A control character (hex 1A) added to the end of text files by
traditional microcomputer programs. This practice was popular
with the Digital Research CP/M 8 bit operating system.
Crash Recovery(TM) refers to the ZMODEM File Transfer Protocol's
ability to resume file transfers that have been interrupted by a
line disconnect from the point where the transfer was interrupted.
Cyclical Redundancy Check (CRC) is a datum (16 or 32 bits) generated
by a cyclic code. The CRC-16 extension to the Ward Christensen
XMODEM protocol provides a higher level of data integrity than the
original XMODEM checksum. A good CRC-16 guarantees detection of
all single and double bit errors, all errors with an odd number
of error bits, all burst errors of length 16 or less, 99.9969% of
all 17-bit error bursts, and 99.9984 per cent of all possible
longer error bursts. The actual performance may be better because
errors that sneak by CRC-16 are often detected by ZCOMM's
Cybernetic Data Recovery(TM).
ZMODEM's 32 bit CRC provides five orders of magnitude more
accurate error detection than XMODEM's CRC-16. It is a billion
times more accurate than XMODEM's 8 bit checksum.
Default is a choice a program makes for you if you do not explicitly
make a contrary choice.
(C) 1994 Omen Tech Inc Chapter 6 Rosetta Stone
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 17
Download is the transfer of data from the host system down to your
computer.
DCE meand Data Communications Equipment. "DCE speed" refers to the
transmission speed between modems.
DTE meand Data Terminal Equipment. "DTE speed" refers to the
transmission speed between modem and the Data Terminal Equipment
(computer).
DTR is an abbreviation for Data Terminal Ready. Data Terminal Ready
is a signal sent by the computer to the modem to condition it to
accept commands or answer an incoming call. When DTR is "dropped"
(switched off), the modem should disconnect from the line.
Execute When a string parameter is executed, it is normally sent to
the remote (modem). If it begins with "@", the remainder is
executed as a ZCOMM command.
Filespec Some ZCOMM commands instruct a remote Kermit server program
to send, receive, print, type, or delete one or more files. The
syntax of this specification is defined by the remote Kermit
server program, not ZCOMM. If filespec contains spaces, filespec
must be enclosed by double quotes.
Flow Control restrains the speed of transmission to prevent loss of
data when a fast sender must send to a slower receiver. Hardware
signals, control characters, and protocol handshakes can be used
to provide restraint, singly or in combinations.
SEE ALSO: handshake command, zmodem w parameter, Flow Control
Chapter 14
Functions are operations supported by ZCOMM, such as a dir, type, s,
r, or t (term) command. A command may set or reset term options,
change a parameter, or perform a function.
Host Operation allows remote access of files and programs.
Iff If and only if.
Integrity in a data transfer protocol refers to the ability of the
protocol to guarantee a correct data transfer provided both sender
and receiver report a successful transfer. Integrity is a
different measure of a file transfer protocol than robustness,
which is a measure of a protocol's ability to complete the
requested transfers in the presence of errors, independent of the
probability of undetected errors.
Kermit ia an error correcting batch file transfer protocol developed
at Columbia University and elsewhere. The Kermit protocol
(C) 1994 Omen Tech Inc Chapter 6 Rosetta Stone
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 18
supports text and binary file transfers with many mainframe
computers whose hardware and operating software preclude
implementation of high performance protocols.
Line Hit A burst of noise on a telephone line may generate modem data
errors. A single "line hit" may garble dozens of characters.
ZCOMM's Error Containment(TM) technology may be used to reduce the
number of characters garbled by line hits suffered in terminal
emulation data capture.
N.B. Nota Bene, Latin for "note well" or "take notice".
Options Options apply to the Kermit, s, sx, sb, s7, st, r, rx, r7, rb,
and rc protocol file transfer commands.
q.v. Quod Vide is Latin for "which see", an invitation to consult
information on the subject mentioned.
Pathname is a complete file name, optionally including disk and/or
directory names.
EXAMPLE: c:/ZCOMM/PHODIR.t
Pathspec ... A pathspec consists of zero or more pathnames.
Unambiguous and ambiguous (with wildcard characters) pathnames may
be specified in any combination. The wildcard filename characters
* and ? are allowed as described in the IBM DOS manual chapter
"Global Filename Characters". In DOS, only the filename portion
of the pathname may contain wildcards.
EXAMPLE: src/cmd/*.c is legal; src/*/foo.c is not.
On 32 bit Unix systems, ZCOMM expands "*" and "?" the way the
shell does. All the shell wildcards may be used including
multiple wildcards, wildcards in directories, and ranges. ~user
expands to the login directory of user, and ~ expands to your home
directory. In addition, `command` takes the output of command as
a series of pathnames.
EXAMPLE: dir */[a-i]* displays all files starting with "a" to "i"
in all subdirectories immediately below the current directory.
An empty pathspec represents all files in the current directory on
the current disk. A disk identifier without any file names
represents all files on that disk's current directory. A
directory pathname expands to all files in the specified
directory.
(C) 1994 Omen Tech Inc Chapter 6 Rosetta Stone
Version 18.18 TurboDial 2.41 Universal Line Printer Edition
ZCOMM User Manual 19
Sequences of the form %svar are replaced by the value (possibly
empty) of the string parameter svar. If svar is not a string
parameter, no substitution is made.
A pathspec may contain any combination of the above, separated by
spaces or tabs.
If pathspec includes a disk specifier (such as a: or b:), ZCOMM
checks the disk specifier against the permissible disk specifiers
in the disks string parameter
The various filename expansions are especially useful in the
context of commands such as wc, sum, crc, find, sb, and sz. For
example, wc applies to all files in the current directory, and
wc dir applies to all files in dir.
ZCOMM pathnames may use / or \ to delimit directories.
Regular Expressions control pattern matching and grouping of text by
the ss and egrep commands. "Magic" characters specify the pattern
matching and grouping processes.
Remote refers to the machine or terminal with which ZCOMM is
communicating. This could be a direct RS-232 connection to a
local terminal, micro, mini, or mainframe, or a timesharing system
accessed through a modem and a global packet switched network.
Restraint See "Flow Control" above.
Restricted For security reasons, ZCOMM is restricted to prevent
unauthorized dial-in users from accessing private data or crashing
the system. Certain commands are illegal when ZCOMM is
restricted, and only specified disk drives and directories may be
accessed.
Review Function Characters output from the remote may be paged and
searched online with the review function. This data may also be
cut and pasted to disk files.
Robustness in a file transfer protocol refers to the protocol's
ability to complete transfers in the presence of errors induced by
line noise or other sources. Robustness is a different measure of
a file transfer protocol than integrity, a measure of the
probability of correct data transfer given a successful completion
of the transfer process.
Script A script is a set of commands that control dialogues with the
user or a remote system.
Script Level refers to the degree of nesting of scripts. Level 0 is
called by the user directly, and each higher level is executed by
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a gosub or other command from the previous level.
Shell Escape is a DOS command or program called as a subroutine from
ZCOMM via a DOS Gateway. The phrase "shell escape" comes from the
Unix(TM) Operating System, whose command interpreter is called
"the shell".
Soft Keys Strings or commands may be assigned to the Soft Keys with
set commands, including those in the telephone directory "setup"
entry executed each time ZCOMM starts. ZCOMM recognizes the forty
function key codes produced by the function keys F1 to F12. FS1
to FS12 are obtained with a Shift key, FC1 to FC12 are obtained
with the Ctrl key, and FA1 to FA12 are obtained with the Alt key.
The cursor keys and extra function keys on 101 key Extended
Keyboards are also recognized.
Strings or commands may be assigned to BS, ESC, Ins, Del, Home,
End, Up, Down, Left, Right, PgUp, and PgDn, overriding their
normal functions in the term function.
String Some commands take a string argument. If a string argument
contains spaces, tabs, and a semicolon, it must be enclosed by
double quotes (shift single quote on the IBM PC keyboard).
Control characters may be included in strings with character
escapes similar to those used by the C Programming Language.
Term Function ZCOMM's Term Function provides the conversational
"connection" between the user and the remote. The term function
captures data from the remote into ZCOMM's circular buffer from
whence it may be displayed, printed, stored in a disk file, or
searched, cut and pasted by the review function.
Term Options Many options are available to modify the way the term
function receives, displays, transmits, and stores data.
Upload is a transfer of data from your computer up to the host system.
Wild Card Many commands allow wild card file names in their pathspec
(q.v.).
Writing When a receive file is open as a result of a create or t
filename command, data in the circular buffer is written out to
the receive file when the circular buffer fills up or when a w or
ALT-W command is given.
XMODEM The Ward Christensen file transfer protocol uses 128 byte
packets, one byte control messages, and a one byte arithmetic
checksum.
XMODEM/CRC A synonym for the enhanced Ward Christensen XMODEM protocol
using a Cyclic Redundancy Check (CRC-16). Newer programs support
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CRC-16 for better data integrity, but reliability is still
compromised by one byte control messages.
XMODEM-1k XMODEM protocol with 1024 byte data packets, CRC-16, and one
byte control messages, sometimes incorrectly called ymodem.
YMODEM YMODEM is a batch file transfer protocol with pathname, date,
file length and other file data in block 0, CRC-16 default, and
optional 1024 byte packets. Many programs claiming to support
YMODEM actually use XMODEM with 1024 byte blocks; use ZCOMM's sx
-k and rx commands with these XMODEM mutants.
XOFF, XON ASCII control characters control the flow of data. XOFF
(Ctrl-S) stops and XON (Ctrl-Q) resumes the flow of data. Chapter
37 provides an ASCII code chart with the names for the control
characters.
ZCOMM is a shareware (User Supported) subset of PCDOS Professional-
YAM.
ZMODEM An advanced file transfer protocol with simplified human
interface, crash recovery, high speed streaming, sensitive 32 bit
CRC, command download, security features, and important file
management functions.
{arg1 | arg2} One of the arguments separated by | is required.
[] Optional argument.
* The special symbol * denotes features not included in ZCOMM. **
Denotes features not included in userialized (unregistered) copies
of ZCOMM.
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7. INSTALLING ZCOMM
If you have registered your copy of ZCOMM, make yourself a working
copy of the ZCOMM distribution disk using the DOS diskcopy command.
Keep the distribution disk in a safe place away from nasty killers
such as disk drives, displays, computers, magnets, motors, and coffee
cups. The only time the distribution diskette should be out and about
is when you are cloning your working copies.
7.1 Installation from Registration Disk
Before installing ZCOMM, you may wish to create a directory for the
ZCOMM files. If so, you must include this dorectory in the DOS PATH.
Otherwise the files may be extracted to the root directory.
The ZCOMM software files are contained in the ZCOMMEXE.ZIP and
ZCOMMHLP.ZIP archives on the distribution disk. Use a standard
"unzip" program such as PKUNZIP to extract files from these archives.
The putsnp program inserts your ZCOMM Serial-Number-Password (ZSNP)
into your working copiy of ZCOMM. Installing a legal serial number
suppresses the pause after the opening message, enlarges the circular
buffer, and enables new commands. The putsnp program prompts for your
Serial/Number/Password (SNP) of the form X123456789. Putsnp checks
for keyboarding mistakes and then verifies that you understand and
agree to the licensing conditions. When you understand and agree to
the licensing conditions, respond with yes (not just y).
Then putsnp prompts for the name of a file to insert the serial number
into. This should be a ZCOMM.EXE file that you have transferred to a
scratch disk, or to an appropriate directory on your hard disk. Do
not write on the distribution diskette unless a nuclear attack is in
progress.
After inserting the serial number in the given file, putsnp asks if
you wish to change the default value for the phone directory pathname
(string parameter phones). This is normally /PHODIR.t. If you wish
to keep the phones file elsewhere, answer "yes".[1] Putsnp then
searches for the location in your copy of ZCOMM that contains this
information. When found, you may enter a new pathname,[2] up to 64
characters.
__________
1. The default value may also be overidden with the PHONES DOS
environment variable.
2. Such as c:/zcomm/PHODIR.t.
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Afterwards, you should copy the help processor files YHP.EXE and
ZMANH.HLP from the disk.
7.2 Installation from ZCOMM*.ARC
If you are using the software provided in ZCOMM*.ARC, be sure to save
the original files for backup, and pass them on to your friends to
fill their communications needs. There are currently three ZCOMM
archive files:
+ ZCOMMEXE.ARC contains the executable program and demonstration
files.
+ ZCOMMDOC.ARC contains this documentation.
+ ZCOMMHLP.ARC contains ZCOMM's tree structured help file and random
access flash-up help processor.
7.3 Installation Continued
The second order of business is to read this manual. There is just no
way you can get your money's worth out of ZCOMM without reading, or at
least carefully scanning, this manual. After all, didn't you get
ZCOMM because you needed something more powerful than that cumbersome,
unreliable, brain-damaged menu driven crock you've been using?
(Perhaps you shouldn't answer that question just yet ...)
You can then edit PHODIR.t to suit your own needs by inserting
directory entries for the systems you wish to call and changing the
phone numbers, account numbers, and passwords on the "standard"
entries for popular timesharing services that you have accounts with.
Be sure to check the setup entry and make any changes you feel
appropriate. Once you have the "feel" of ZCOMM, you will want to
remove the automatic menu invocation at the end of the setup directory
entry.
Chapter 10 gives a line by line tutorial for setting up your telephone
directory assuming you are using a standard modem.
If you are using a computer that runs at non standard clock rates
(e.g., 8 mHz 8088 instead of 4.77 mHz) or with an enhanced CPU chip
(NEC V20), you will need to set special values for the a and b numeric
parameters as described in Chapter 24.
**** WARNING **** Although ZCOMM is well behaved as communications
programs go, some memory resident programs, special keyboard
modifiers, print spoolers, or special display drivers, may cause
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problems.
**** WARNING **** Since ZCOMM uses interrupts to read data from the
serial ports, each serial port must be strapped for its proper
interrupt vector. Some communications programs assign both IRQ3 and
IRQ4 while operating, so they will operate even if the serial ports
are not strapped properly. Since ZCOMM only assigns the interrupt
vector of the port in use, incorrect IRQ level strapping will crash
ZCOMM. Check the serial port addresses and vectors with the
information given ith the port command in Chapter 19 if you encounter
trouble starting ZCOMM.
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8. UNLEASHING THE MODEM
8.1 Modem Cabling
ZCOMM and its supplied scripts require the following circuits for
mormal operation. When using an external modem, the modem cable must
connect pins 2, 3, 7, 8, and 20. This connects Transmit Data, Receive
Data, Signal Ground, Data Carrier Detect, and Data Terminal Ready.
ZCOMM supports hardware flow control on most systems.
In general one should use a full modem cable.
Direct connect applications (NULL MODEM) can get by with just the two
data leads. Such applications do not use any dialer scripts.
8.2 Hardware Interface
ZCOMM accesses serial ports at the standard IBM COM1 and COM2
addresses. Zcomm also has definitions for COM3-COM18 as described
under the port command. The portx command may be used to access
8250/16450/16550A type serial ports at non standard addresses.
When a port is selected, a quick hardware check is made to verify the
existence and minimal functionality of the port. If this test fails,
the message Port N Defective is displayed. An incorrect port switch
or strap (jumper) configuration is the usual cause of this message.
This check does not guarantee the port is connected to the proper IRQ
line. If the port is not configured to use the proper IRQ line, Zcomm
will not talk to the port, and the computer may lock up.
Some 8250 UART devices (used by serial interface adapters and internal
modems) do not respond correctly when the software turns the
transmitter interrupts on and off. High speed communications programs
such as ZCOMM require properly functioning UART chips. We recommend
the National Semiconductor NS16550AN/NS16550AFN.
8.3 MODEM environment variable
The advanced dialing scripts use two script subroutines to generate
dialing commands for your specific modem. The top level routine is
the adial subroutine in the main phones.t file. The adial routine
must be in your dialing directory (phones.t) and it must be enabled
with the following command in phones.ts or the setup entry in your
dialing directory:
set mcommand "gosub adial" : select advanced dialer
Adial's top level routine handles alternate number lists and
operations pertinent to all modems.
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Adial uses the MODEM environment variable to identify the disk file
containing the modem specific dialer. The value inherited from the
environment may be overridden with a set command. Adial searches for
this file in the directory specified by the lib string variable. The
following dialer files are currently provided in dialers.zoo.
Additional dialers will be described in dialers.doc, part of the
dialers.zoo archive.
The phomast.t starter script can also be made to use the advanced
dialers by uncommenting the following lines:
: set mcommand "gosub adial" : select advanced dialer
: if "!%MODEM" set MODEM hu96.t : for modem specific
dialer
The second line above should be changed to suit your modem.
ax9624.t MicroCom AX/9624c with MNP Class 6. This modem includes a
pseudo full duplex 9600 bps speed.
cs3820.t AT&T Paradyne Comsphere 3820, DataPort Modem
hst.t U S Robotics HST Dual Standard
hu96.t Hayes V series Ultra Smartmodem 9600 (v.32/v.42)
hv96.t Hayes V series Smartmodem 9600
mmv32b.t Multitech MultiModem V32 with V.32bis.
mmv32.t Multitech MultiModem V32 with MNP.
mm224.t Multitech MultiModem 224 without MNP. This dialer
supports many 2400 bps modems with little or no
modification.
mm224e.t Multitech MultiModem 224E with MNP.
sm1200.t Hayes Smartmodem 1200
supra.t Supra FAXModem V.32bis
tb.t Telebit TrialBlazer
Selecting the proper modem type takes two steps. First the file name
for the desired dialer must be specified in your DOS (or Unix)
environment.
NB. The following must be entered without extra spaces.
EXAMPLE: C>set MODEM=mm224e.t (DOS)
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EXAMPLE: $ MODEM=mm224e.t; export MODEM (Unix)
Second, the Zcomm lib string variable must be set in the phones.t
setup phone directory entry or in phones.ts.
EXAMPLE: set lib "C:/ZCOMM" (DOS)
EXAMPLE: set lib "/usr/lib/yam" (Unix default)
When setting up for a particular modem type, be sure to configure the
modem's switches and Non Volatile RAM (NVRAM) for use with ZCOMM. If
nonstandard NVRAM settings interfere with ZCOMM's initialization scrip
for that modem, you may have to manually restore the NVRAM contents to
the factory default. The supplied scripts expect to see the factory
default VERBAL RESULT CODES (not result digits).
The adial dialing script supports a number of modems under control of
the MODEM environment variable.
8.4 New and Improved Modems
Modem manufacturers are constantly refining their products, adding new
features and making subtle subtle changes in existing features. If
your modem is not listed in one of the following subchapters, please
read all the subchapters and use the suggestions that apply to modems
similar to yours.
To obtain the full performance your modem provides, you can create a
dialer optimized for your modem. Copy the dialer script for a similar
modem into a new file.
Next, edit the initialization strings in the dialing scripts to take
advantage of new modem features.
8.5 Pulse Dialing
If your telephone line requires rotary (pulse) dialing, set mprefix to
ATDP with a command in the setup telephone directory entry. This
procedure is detailed in Chapter 9.
8.6 Cellular Radio
Some modems (AT&T Keep In Touch) have special settings to optimize
operation when making calls over cellular radio. The call cellular
command sets the string parameter cellular that instructs certain
dialers to optimize operation for cellular radio.
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Some modems have special options to enhance operation when accepting
calls over cellular raidio or other difficult, unstable connections.
The command: call init,cela sets these parameters on some dialers.
Please check the source code for the dialer you are using for cellular
support.
8.7 MNP, V.42, X.PC, AFT
More and more modems support one or more error correcting link level
protocols such as MNP and V.42. Modem to modem link level protocols
correct most transmission errors reducing the frequency of garbled
text and file transfer retries. Modern link level protocols increase
transmission speed by eliminating start/stop bits and redundant
information.
When MNP is enabled, the calling modem sends control characters to
interrogate the answering modem for MNP. These characters can prevent
logging in to some timesharing systems, packet switched networks, and
bulletin boards. Non streaming protocols such as XMODEM, YMODEM, and
Kermit usually give faster transfers without the delays introduced by
MNP and other link level protocols. Accordingly, ZCOMM's dialing
scripts are designed to place calls with MNP disabled by default.
No modifier is used for AFT, V.42, or V.42bis link protocols. We have
not experienced log-in or throughput problems with these protocols, so
we made them the default.
There are unfortunately exceptions to every rule. A few modems enable
V.42 only when MNP is commanded. The dialers for these modems default
to MNP and V.42 enabled, and allow the /dir dial modifier to disable
error correction.
The dialer scripts support one or more of the following modifiers:
/300 Force a connection at 300 bps. Dropping down to 300 bps may
be necessary to get a reliable connection in the Oregon Rain
Forest.
/1200 Force a connection at 1200 bps.
/2400 Force a 2400 bps connection.
/9600 Force a 9600 bps connection.
/nop Suppress the detection of call progress reporting. This may
be used to prevent the modem from misinterpreting an unusual
ringing sound as a busy signal.
/c Enable modem compression.
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/fast Force a high speed PEP connection (refuse a slow speed
connection).
EXAMPLE: 123-4567/fast
/man Some modems incorrectly abandon a call attempt when they
"hear" sounds they aren't programmed to understand. For
example, some TrailBlazer modems abort the call with a
spurious "NO CARRIER" message when they hear the sound of the
telephone "ringing". If that doesn't dump the call, the
TrailBlazer may dump the call when the answering modem emits
an echo suppressor disabling tone before sending the standard
Bell 103 answer tone. Under these circumstances the only
solution is to listen to the sounds yourself and tell the
modem exactly when to start listening. With the /man
modifier, the modem remains in command mode after dialing the
phone number and ZCOMM enters the term function to display
messages from the modem. When you hear the called modem's
answer tone, hit F1 to exit the term function. The dialing
script then sends an "ATO" to the modem to attempt a normal
data connection. Some practice may be necessary before you
get the right timing. If you hit F1 too late the answering
modem may timeout before the modems can handshake and enter
data mode.
/dir Use direct connection without speed buffering and/or error
control (MNP, V.42, etc.).
/cell Adjust the modem for best operation over cellular radio
connections.
/mnp Require MNP link level connection. Do not connect if MNP
fails.
EXAMPLE: 123-4567/mnp
/mnp_s Require MNP link level connection, use software flow
control.[1] Do not connect if MNP fails.
/a_mnp Request MNP link level connection.
__________
1. Software flow control in the modem is not compatible with XMODEM,
YMODEM, Sealink, Clink, or WXMODEM.
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/a_mnp_s Request MNP link level connection, use software flow control.
/xmodem Enable "XMODEM spoofing" on Trailblazer modems. (Not
recommended)
/kermit Enable "Kermit spoofing" on Trailblazer modems. (Not
recommended)
/v22 Use V.22 modulation on a 1200 bps call.
/c:modifier Optional modem dependent modifier string
8.8 High Speed Modems
The new generation of high speed dial-up modems presents special
challenges to users and system integrators.
These modems transmit data at speeds from 110 to 38400 or more bits
per second. This range of speeds poses special problems communicating
between the computer and the modem. Lower speed modems examine the
traditional "AT" command prefix bit by bit to lock onto the computer's
transmission speed instantly. Many modems which recognize commands at
widely varying speeds can not use this technique. A number of
alternate techniques have been developed, each with its own advantages
and problems.
+ Lock the interface to the highest transmission rate. This avoids
the programming required to synchronize the modem's and computer's
speeds. Flow control must be used when the interface speed is
locked to prevent the computer from sending data more rapidly than
the modem can buffer and transmit it. This local flow control is
usually accomplished with hardware signals. When such an
arrangement is used to communicate over networks that must assert
their own flow control (with XON and XOFF), data flow regulation
must respond to both hardware (RTS) and software (XOFF) signals.
The handshake both command should be used whenever the modem's
interface speed is locked and transmission over networks or to
timesharing systems is desired.
Locking the interface speed to 9600 or 19200 bps while
communicating at 1200 and 2400 bps should be avoided unless all
links in the transmission path have low error rates.
Most modems do not recognize XOFF characters from the remote
computer, so characters stored in the modem's buffer will be
transmitted for a period of time after an XOFF is received. This
causes loss of data with some computer services.
When the interface speed is locked at a higher speed than the
actual data transmission, an excessive amount of data may be
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