CARBON COPY MODEM DESCRIPTOR UTILITY
Table of Contents
RELATIVE SOFTWARE VERSIONS
MODEM DESCRIPTOR TABLE
Creating and Maintaining Descriptors
EDIT MODEM DEFINITION MENU
Data Field Descriptions
ADD ACTION SYMBOL MENU
HARDWARE and SOFTWARE RELATIONSHIPS
Hardware Leads and Software Commands
Software Register Values
Result Code Values
The MODEM DESCRIPTOR is the file MODEM.DSC which is distributed with the
Carbon Copy PLUS and CCExpress software packages. The following is a
description of the utility CCMODEM.EXE which is used to create and maintain
the modem descriptor file.
The MODEM.DSC file contains not only modem entries, such as MICROCOM and
Hayes, but also communciation-switching system entries, such as ROLM and
GANDALF. The Carbon Copy PLUS or CCExpress software in which the modem
entries are displayed are the CCINSTAL.EXE and EXINSTAL.EXE utilities.
The entries of the descriptor file are displayed within these utilities
for the end user to select a "MODEM TYPE" from the list. The list represents
the modem descriptor created and maintained by this utility. Each modem entry
is composed of data fields which dictate the performance relationship
Carbon Copy PLUS and/or CCExpress software. These data fields and their
impact on performance will be described under the "EDIT MODEM DEFINITION"
RELATIVE SOFTWARE VERSIONS
There have been several versions of Carbon Copy with copies of the
CCMODEM.EXE utility of the same version number. There are several options
contained in the current CCMODEM.EXE utility which are not functional for
earlier versions of Carbon Copy or CCExpress. It is assumed that any customer
needing this documentation is a recent customer having Carbon Copy PLUS
version 5.0 or an existing customer having a version of Carbon Copy 4.0 or
CCExpress version 2.0. This document assumes that the Carbon Copy version 3.0
and earlier will have the Carbon Copy version 4.0 UPGRADE software.
Throughout this manual there will be references to Carbon Copy, Carbon Copy
PLUS and CCExpress versions, the versions have software code relationships
which cause some data fields and action symbols to be version dependent.
We will attempt to explain the level of behavior which can be expected from
earlier software versions or whether the feature is supported in earlier
versions. This document is written focusing on the communication features
of Carbon Copy PLUS version 5.0 and CCExpress version 2.0.
The modem descriptor table did not exist in Carbon Copy version 2.14 or 2.15.
Carbon Copy version 3.0 was its beginning, yet only 30 modem entries were
possible with version 3.0. The modem types were displayed in the CCINSTAL.EXE
utility by toggling through the list one-by-one. In Carbon Copy version 4.0
also referred to as Carbon Copy PLUS, the modem table in CCINSTAL.EXE became
a point-and-chose list with 60 modem entries. CCExpress became a product of
the logic based on Carbon Copy PLUS, therefore, it uses the same modem table
and performed in exactly the same manner with modems and data-switches.
The modem performance became more flexible with Carbon Copy version 5.0
which required several additional features of the CCMODEM.EXE utility.
MODEM DESCRIPTOR TABLE
@Creating and Maintaining [email protected]
There are 58 modem entry locations which can be used for building modem
descriptors or building data-switch descriptors. The 59th location is
reserved for use exclusively by MERIDIAN Technology. The 59th location should
not be used; it is tied to a special area in the software code which performs
"RING INDICATOR" logic used exclusively or switch-related behaviors. Placing
a modem descriptor in this location may cause errors in code performance.
The first modem entry "NO MODEM" is for use exclusively for communication
through a NULL-MODEM cabling device to another PC or a RS-232 cable directly
to a host system. Since the first modem entry is not EDITable, it is not
included in the modem location numbers. All specific performance criterion
defined for the "NO MODEM" entry are coded within the software and can not
be changed by the end user. If some specific behavior is required with
the use of the direct connection, then a specific modem descriptor must be
created for controlling that performance.
There are several locations at the end of the list which are "Not Defined" and
can be used to create special modem descriptors.
Since CCMODEM.EXE does not create a backup copy of the MODEM.DSC file, it
is strongly recommended that you COPY the file to a backup file name. Any
changes made to the modem descriptors during the run of CCMODEM.EXE will be
lost in the case of a power disruption or system re-boot; the MODEM.DSC
file is updated following the selection of the X-eXit option from the
CCMODEM.EXE menu screen.
@Menu [email protected]
insert the main menu screen here
The following describes the options used on this menu:
# - MODEM NUMBER to edit the modem descriptor
When entering the number of the modem descriptor's location the
"EDIT MODEM DESCRIPTOR" screen will appear, displaying the appropraite
A - ALPHABETIZE
This option alphabetizes or sorts the modems in ascending
lexigraphical order (ascii character set order), starting with
0 thru 10, then 'A' thru 'Z' followed by 'a' thru 'z'. This makes
it necessary to be observant when mixing upper and lower case characters
in the modem's NAME field.
C - COPY
When selecting this option, a prompt will appear
FROM: _ _
requesting the source modem descriptor number FROM which the data
field definitions will be copied. After entering the second digit
of the descriptor number or press following a single digit
descriptor, a second prompt will appear
TO: _ _
This prompt requests the destination modem location TO which the
descriptor's definitions are to be copied. Since the modem description
is copied exactly FROM one location TO the other, the two descriptors
will have the same name. It is suggested that the name of one of the
descriptors be altered since only the modem names appear on the
CCINSTAL.EXE modem screen.
To clear a descriptor entry, you could copy a modem descriptor reading
"Not Defined" into the descriptor location to be blanked. There is a
second method of clearing described under the MODEM NAME field in the
"Data Field Description" section.
Q - QUIT
This command will cause the CCMODEM utility to return to DOS with no
updates recorded in the MODEM.DSC file.
X - EXIT
This command will cause the CCMODEM utility to return to DOS, saving
all changes permanently in the MODEM.DSC file; since these updates
are permanent, a backup copy is suggested prior to EDITing any modem
EDIT MODEM DESCRIPTION MENU
After selecting a modem location the "EDIT MODEM DEFINITION" screen
will be displayed. The data fields appearing in this screen will be
empty as you are editing a modem descriptor which is "Not Defined".
The cursor will appear at the beginning of the MODEM NAME field. If you are
editing a modem descriptor which has been defined (NAMED), then the
data previously defined will be displayed. The cursor will appear on the
first character of the NAME field and the reverse video or color bar will
be displayed across the data field. The cursor bar indicates the data field
which is CURRENT for editing.
To enter data in the current data field, type any character on the keyboard
or select an ACTION SYMBOL to be inserted in the data field.
To blank a descriptor, use the DEL key to delete all characters until the
reverse video or color bar disappears, then "RETURN to MENU". The
location previously selected for edit will then state "Not Defined". Each
field in the modem descriptor location has been cleared. To move from data
field to data field use the appropriate scroll key.
The following is an example of a MODEM descriptor as it appears in the
EDIT MODEM DEFINITION screen:
insert example of MICROCOM AX-AT modem here
@Edit [email protected]
There are several special edit keys for use in editing the modem's
[F1] Add Action Symbol -- You may go in and out of the "ADD ACTION SYMBOL"
screen selecting symbols to be placed within the
descriptor field. The action symbol screen is
described with more detail in the next section. The
data field currently being edited is not completed
until the "RETURN" key, the down-arrow key, or
[F10] function key have been pressed.
[F10] Return to Menu -- The [F10] option performs different update behaviors
for CCMODEM.EXE version 5.0 and earlier, than the
With versions 5.0 and earlier, the [F10] option
exits to the main menu and all changes to the data
field being edited are lost. With version 5.1,
the currently edited field is saved when the [F10]
option is chosen.
[ESC] the ESCape key -- restores the data field currently being edited
to its previous values.
[INS] the INSert key -- inserts the ascii space character at the current
cursor location and moves the remaining characters
in data field one space to the right.
[DEL] the DELete key -- deletes the character at the current cursor location
and moves the remaining characters in the data field
one character to the left.
Arrow-Editing keys -- The RIGHT and LEFT arrow keys move the current-edit
cursor position across the current character to next
character in the data field.
The UP and DOWN arrow keys move the cursor bar
either up or down to the next line field to be
edited. All edits performed to the current data
line are saved if either of these keys are pressed.
The can be pressed to restore the data field
if edits were erroneously entered. If the data
line being edited is the last "RESPONSE STRING"
field and the DOWN arrow key is pressed, then the
software returns to the main menu, "Carbon Copy
Modem Descriptor Program", and the edits are saved
in the modem descriptor table in memory.
Data Field Descriptions
References below to code or software imply the Carbon Copy and CCExpress
code. The data field descriptions concentrate on modem behaviors. If a
data-switch descriptor is to be built, then one must be very careful to
consider the types of calls which the data-switch performs. The "data-switch
to data-switch" calls as well as "data-switch through modem pool calls"
should be provided for within the same descriptor. If this is not possible
it is suggested that a descriptor for each be built.
The following describes the definition of each of the data fields within
the "EDIT MODEM DEFINITION" screen:
MODEM NAME (19 characters)
The name entered in this field will be the name which appears on
the main menu of this utility as well as the MODEM TABLE menu of
CCINSTAL.EXE and EXINSTAL.EXE utilities.
RESET STR 1 (63 characters)
RESET STR 2 (63 characters)
Reset string #1 and #2 are sent to the modem in one continuous stream.
They are sent once when the Carbon Copy executable is loaded, then again
when disconnecting from the other user. The reset strings are
also sent whenever the option under DATA LINK MAINTAINENCE for
RESET THE DATA LINK is selected.
Note: the maximum command-line length (number of characters between
carriage returns) by most modems is 40 characters,
excluding spaces. When building a descriptor one must insert
carriage returns followed by a delay, keeping command-line length
within character limit.
There are several modem descriptors whose reset strings are broken into
several seperate "AT" commands. The reasons for these seperations maybe
one of the following:
a) if the command is needed for one of the manufacturers modems
but may cause an error to be returned from other types of
manufacturers modems, then it is seperated from the other
commands by a carriage return and delay symbols. This will
cause the command causing the error to be discarded by modems
with can not perform the command but allow them to perform all
other commands within the reset string. For each of the
command-lines (command data from AT to the carriage return) the
modem only returns one result code.
b) if the reset string one command-line extends through to reset
string 2, and the total number of characters since the previous
carriage return or start of the commandline may be only forty
All result codes returned while transmitting these RESET STRINGS to the
modem are discarded by the software. The software does not check any
result code data until after dialing the phone number.
DIAL PREFIX STRING (31 characters)
This string is sent prior to the phone number in each call placed.
At the time in the Carbon Copy code when this string is sent, the code
assumes that the modem is still in the command state from the reset
string execution. This string is typically the modem's DIAL command.
Note for PBX: if the user must call through a PBX using "two stage"
dialing, this would be the location where the modem pool's
phone number would be located. Otherwise, this would be
the location for requesting the switch's attention to
initiate calling another extension in the switch.
ATTENTION STRING (19 characters)
The attention string is represented by the diamond symbol. This string
contains the breaks or escape character sequence necessary to get the
modem's attention and force it into the command mode. Since the modem
can only process commands in the command state, the diamond symbol which
represents ATTENTION STRING performance should be placed in the front of
the RESET STR 1.
The ATTENTION STRING has two uses; for versions of Carbon Copy 3.0, 4.0,
and 5.0. In Carbon Copy version 5.0 where "FULL" reset is choosen and all
performances of versions 3.0 and 4.0, the attention string is used to
send the attention/escape characters followed by the remainder of the
RESET STRING. In Carbon Copy 5.0 where the "PARTIAL" reset is chosen
only the ATTENTION STRINGS contents are sent to the modem; the RESET
STRINGS are only sent when the executable loads into memory and when the
"RESET the DATA LINK" option is performed (described under RESET STRING).
AUTO-ANSWER STRING (19 characters)
This string is sent when the "Auto-Answer mode" of Carbon Copy PLUS
is toggled to the ON state (ENABLE Auto-Answer). This option is
within the [F8] DATA LINK MAINTENANCE submenu.
NO AUTO-ANSWER STRING (19 characters)
This string is sent when the "Auto-Answer mode" of Carbon Copy
is toggled to the OFF state (DISABLE Auto-Answer). This option
is within the DATA LINK MAINTENANCE submenu. It is also sent following
the RESET STRINGS when the "Optional Configuration Parameter" from the
CCINSTAL.EXE or EXINSTAL.EXE screen is set to
NORMAL ANSWER MODE ... NO ANSWER.
CC VOICE to DATA STRING (19 characters)
This string is sent to the modem when the system running CC.EXE has
previously chosen the option, "SWITCH DATA to VOICE MODE", from the
main control screen and is returning to the DATA mode. For the user
to return to data modem he must select the option, "SWITCH VOICE to
DATA MODE", from the main control screen menu.
This string commands the modem to go to ANSWER mode as the other
modem is instructed to ORIGINATE the carrier negotiation. ANSWER
and ORIGINATE are modem terms for LISTENING and TALKING on the phone line;
one modem must be setup for listening while the other, for talking.
CCHELP VOICE to DATA STRING (19 characters)
This string is sent by the system running CCHELP.EXE under similar
circumstances to the data string described above; this system's modem
is instructed to ORIGINATE the carrier negotiation between the modems.
Frequently, the modem descriptors will have an "X1" command embedded in
this string due to the "X4" (FULL call progress monitoring) command
which is the preferred command in the reset string. The progress
monitoring may report result codes when placing the call; this will
confuse the Carbon Copy code which is testing the result code data
against the CONNECT STRINGs. The Carbon Copy code will start comparing
the result code returned during the call against the CONNECT STRINGS
instead of the result code returned after carrier is negotiated. This
will prevent a successful SWITCH back to the data mode.
INITIAL BAUD RATE
This is the initial baud rate which will appear in the "BAUD RATE" field
on the CCINSTAL.EXE "SYSTEM PARAMETER" screen when this modem type is
selected. The baud rate value must be one of the ACTION SYMBOLS. The
corresponding value is stored in the last character of the modem's name
field (twentieth character) in the modem descriptor file.
This feature is not supported in Carbon Copy version 3.0 and should be
left empty for every modem descriptor in the list when executing the
CONNECT STRING (19 characters)
There are eight of these fields which must hold each of the modem's
result codes. Carbon Copy examines each of the connect strings for
a match after receiving the result code from the modem. The carriage
return character can not be examined, therefore data having an embedded
carriage return can not be used in the connect string. If the result
code has an embedded carriage return only the first characters up to the
carriage return character should be placed in the CONNECT STRING. Make
sure that these characters define a unique result code. If the
characters occur in more than one result-code string, then find a command
for the modem which will change the result codes reported to be unique
result codes (for example: from verbose result codes to non-verbose
codes where instead of words you will have digits).
To find the RESULT CODEs returned by your modem or data-switch look
in the modem manufacturer's documentation under RESULT CODES or
RETURN CODES. Data-switches do not always return the connecting speed
to the user. If the connecting speed is not returned a manual SWITCH
dialing process should be set-up which will be described under
Most of the modem descriptors contain each of the result codes
indicating a CONNECT SPEED as well as the phone line BUSY result code.
If there are more than eight result codes (usually high-speed and error-
correcting modem descriptors), then the result codes stored in the
CONNECT STRINGs are selected by the following criteria:
a) Error correcting modems all error-free connecting speeds are
b) Standard settings of 2400, 1200, then 300 (600 also included
when space permits),
c) On modems maintaining a fixed DTE rate, where all baud codes
can not be examined, use a VERBOSE setting in the reset string
and as many unique characters to represent the other connections;
example the word CONNECT could represent CONNECT 2400 and
The following rule must be implemented when storing the connect strings
in the data fields:
a) Non-Unique entries must be ordered with the longest character
string stored in the CONNECT STRING above the shorter string.
Connect String: CONNECT 2400/REL
Connect String: CONNECT 2400
Connect String: CONNECT represents all other
connections 1200, 600,
Connect String: 10 represents connect 2400
Connect String: 5 represents connect 1200
Connect String: 1 represents connect 300 with
the X1 or X4 used in reset str
the connect 2400 string must be above the connect 300
b) When cursor bar is on the field, the reverse video must end on
the last character; otherwise, a space character will be considered
a part of the result code. Since all connect strings are ended
in the modem descriptor file with a null character (indicating
end of string at the Null), the test for a match will fail since
the space character will also be tested.
RESPONSE STRING (19 characters)
There are several standards which are implemented in the RESPONSE
STRINGs. If the COMM port's baud rate on the PC must change to match
the connecting speed of the modem, then four .5-second delays followed
by the baud rate ACTION SYMBOL should be stored in the RESPONSE STRING.
The baud rate symbol must match the same rate that the corresponding
CONNECT STRING reports from the connection. The preceeding delays are
to allow the modems to be quiet before the software exchanges data.
NOTE to leased line and PBX users:
Since leased lines and PBXs often maintain Carrier Detect high, it
maybe necessary to place the Carrier Detect symbol in the front
of the response string. This causes the software to check for the
carrier before proceeding. (Carbon Copy version 5.0 software only)
NOTE for ERROR CORRECTING MODEMS
With these modems the error-free link symbol should be inserted in
the front of the response string followed by 5 of the .5 second
delays. This allows enough synchronization time before the software
begins the login process.
If the modems correctly negotiate carrier (meaning white tones complete),
following which they immediately drop the call without having completed
the connection, then a special symbol "NO RTSOFF on Sync-up" should be
inserted in the front of the response string. The modem may be going
back "on-hook" due to Carbon Copy software performing the sync-up pulls
the RTS lead to low immediately after the password is sent. This symbol
is available for use with version 5.0 only; there is a patch which can be
performed against version 4.0 of the software.
ADD ACTION SYMBOL
There are currently 21 action symbols which can appear as embedded characters
within the modem descriptors. Some of the symbols are only relevant for
version 5.0 Carbon Copy software and later, meaning that they may cause other
software versions to perform incorrectly. The action symbol descriptions
follow in the order in which they appear on the sub-menu,
"EDIT MODEM DEFINITION ACTION SYMBOLS". Each of the following elements
are described with their related software behaviors. The element's storage
within the string maps to a special symbol for use by the software and in
no way reflects the ascii character which the element may be named.
CARRIAGE RETURN -- this embeds a carriage return in the data stream.
.5 SECOND DELAY -- this causes the software to perform a half-second delay
during which data retention or discard is dependent on the
location in the code. Delays performed during the
response string cause incoming data from the modem to be
SEND BREAK -- This performs a 200 millisecond break to the data stream.
SEND ATTENTION -- this sends the data contained within the ATTENTION STRING
data field from the EDIT MODEM DEFINITON menu's data field.
This symbol is typically the first or second character in
RESET STR 1.
SET ERROR FREE LINE -- This informs the software that the Carbon Copy
proprietary protocol will not be used and no checksum
verifications are to occur on the data packets sent
during a connection. This setting should only be used
when the modems or data-units linking the PCs are
"ERROR CORRECTING". Error-correction is assumed to
be performed between the two connecting units which
would guarantee that the data passed to the receiving
PC is exactly what was sent from the transmitting
This symbol should be inserted in the RESPONSE STRING
which corresponds to RELIABLE or PROTECTED result codes.
The symbol should be followed immediately by five .5
second delay symbols. This delay is necessary. If this
symbol is placed in the RESET STRING, then the software
will assume that every connection is "ERROR FREE" unless
the RESET ERROR FREE LINE symbol is placed in non-ERROR
FREE RESPONSE STRINGS.
RESET ERROR FREE LINE -- This informs the software that the Carbon Copy
proprietary protocol will be used to check for data
line errors. The default for both the Carbon Copy and
CCExpress software is not an error free line it
assumes error checking is necessary.
CONNECT SEQUENCE -- This instructs the software to send the Carbon Copy
proprietary connecting sequence. This is used only in the
NO CONNECT SEQUENCE -- This instructs the software to inform the user that
the connection could not be made. This is used in
the RESPONSE STRINGS where circumstances from the
modem indicate that carrier could not be successfully
SELECT ALT. DIVISOR TABLE -- This instructs the software to use an alternative
UART clock divisor when performing data throughput
to the modem. This is used in the beginning of
the RESET STRING before the attention symbol is
SUBSTITUTE RING COUNT -- This instructs the software to use the RING COUNT set
by the CCINSTAL.EXE utility and replace any succeeding
digits with that count when setting up the modem.
*LINE FEED -- This instructs the software to send the ASCII LINE FEED character
in the data stream. There is a similar symbol which can be
inserted by the CCINSTAL.EXE utility in the CALL TABLE's phone
*NO RTSOFF ON SYNC-UP -- This instructs the software to maintain the RTS lead
immediately following the completed carrier
negotiation. The default behavior in the software is
to pull the lead LOW for .5 seconds following the
sending of the password or LOGON packet from the CC
side. This symbol should be used only as the first
character in the RESPONSE STRING where applicable.
The RTS sync-up process was necessary for version
2.14 and 2.15 of Carbon Copy.
*WAIT FOR CARRIER DETECT -- This instructs the software to test the
CARRIER DETECT lead for HIGH, indicating that
carrier is present, then continue processing. If
carrier is not present, then WAIT FOR for CARRIER
DETECT lead to become high. This is used in the
RESET STRINGs or RESPONSE STRINGs. There is a
similar symbol which can be inserted by the
CCINSTAL.EXE utility in the CALL TABLE's phone
*SET BAUD 38,400 -- Change PC RS232 port speed to 38,400 bits per second
SET BAUD 19,200 -- Change PC RS232 port speed to 19,200 bits per second
SET BAUD 9600 -- Change PC RS232 port speed to 9600 bits per second
SET BAUD 4800 -- Change PC RS232 port speed to 4800 bits per second
SET BAUD 2400 -- Change PC RS232 port speed to 2400 bits per second
SET BAUD 1200 -- Change PC RS232 port speed to 1200 bits per second
SET BAUD 600 -- Change PC RS232 port speed to 600 bits per second
SET BAUD 300 -- Change PC RS232 port speed to 300 bits per second
* These action symbols may only be in descriptors built for use with
Carbon Copy PLUS version 5.0 and later and CCExpress version later than
SETUP REQUIREMENTS FOR BOTH HARDWARE SWITCH OR SOFTWARE PROGRAMMABLE CONTROL
DTR Data Terminal Ready should follow the DTE device (PC system)
&D2 standard software setting
DCD Carrier Detect should follow true carrier from the telephone line
&C1 standard software setting
DSR Data Set Ready should always be held high by the DCE device(modem)
&S0 standard software setting (usualy a default)
RI Ring Indicator should come high on the incoming call ring and
remain low when carrier is high. Some modems have
an optional setting.
X4 Extended Result the extended result code set must be set to at
Code least X1 in order to allow the standard 2400 and
1200 baud modems to give baud rate related result
codes. The preferred setting is X4 which is
full "CALL PROGRESS MONITORING". The X1 and X4
settings detail the true connecting speed by
returning "CONNECT nnnn" where nnnn is the speed.
When the nonverbose setting is selected, then this
returning connection speeds must be digits
E0 Echo OFF The local echo is turned OFF due to the length
of time the modem's typically require to return
the echo. If this feature is ON, it tends to
cause many modems to lose characters, causing
an error in its command processing. If the echo
feature is necessary in TERMINAL EMULATION use,
then the "DUPLEX" feature should be set to "HALF"
in the "SETUP CONFIGURATION" screen and/or the
"EMULATION ENTRY" screen within CCINSTAL.EXE's
Q0 Quiet OFF The QUIET mode refers to the call progress
monitoring and/or the return of the result codes.
It is critical for the result codes to be returned;
this is the way the Carbon Copy software
can determine the baud rate of the connection and
the protocol link type for error-correcting modems.
Full progress reporting, however, is desired.
V0 NONverbose The NON verbose format is typically used.
The exceptions for which the verbose format is
used have been described above under the
"CONNECT STRING" definitions.
S0=?1 Answer Ring Count The question mark in answer ring count represents
a symbol character which is the "Substitute Ring
Count". This symbol is always followed by a one.
If the ring count which is setup by the CCINSTAL
utility is "DEFAULT", then a ring count of 1
is used (no substitution is made). Likewise, if
six is setup as the ring count, then the number
six will be substituted when the Carbon Copy
software sends the RESET STRing issuing this
S7=255 Wait for Carrier The Carbon Copy software beginning with version 5.0
After Dialing has a "DIALING TIMEOUT" field in its configuration
(set by CCINSTAL.EXE). This command allows the
Carbon Copy software to use the configuration
setting for determining dialing time limit, after
which it pulls the DTR lead low (halts the
dialing process). It is recommended to set the
S7 register value to the modem's maximum timeout
S10=40 Delay before This limit is the maximum time the modem can
Hanging-Up on Loss stay "ON-Line" when the carrier has been lost or
of Carrier interrupted. If one has "CALL WAITING" on the
phone line or telephone line noise, then carrier
can be interrupted. Some Error-Correcting modems
have Error-correction problems with a timeout
exceeding 3.5 seconds. For standard modems the
4 second timeout is sufficent.
There are standard settings which we have chosen with error correcting modems
for use within the modem descriptors.
1) Chose Verbose Extended Result Codes where a modem manufacturer's modems
can return more than seven speed differences and a BUSY result code;
otherwise, chose Numeric Extended Result Codes.
2) Select a setting for fixed DTE baud rate. This allows the modem
to perform buffering and data compression to its maximum efficiency.
3) MNP flow control must use hardware bidirectional flow control.
Carbon Copy uses bidirectional flow control in all communications.
The XON/XOFF logic within modems must be set to PASS-THROUGH logic
in order that the software receive these characters in both file
transfer and remote communications.
4) Use AUTO-RELIABLE link negotiation to allow the modem to connect
to both the error correcting modems and standard compatibles.
Setting a modem for either NORMAL or RELIABLE connections,
restricts connections to one kind of connection or the other.
The circumstances where this restriction should be performed would be
where the carrier negotiations can not be completed with auto-reliable
answertones. Two modem descriptors should be setup for the end user.
There should be a descriptor providing access to the error-correcting
modems using the same protocol with a RELIABLE descriptor, and a
descriptor for use with those modems using NORMAL carrier negotiations.
The limitations are that the operator must know that the MODEM TYPE at
both the calling end and answering end is setup compatibly by the
5) Hayes V-Series can not operate in an error-free link, the result codes
returned for 2400 and 1200 settings have embedded carriage returns.
Hayes Link Type MNP Compatible Baud Rate Link Type
----- --------- -------------- --------- ---------
14 PROTECTED 33 19.2 RELIABLE
12 PROTECTED 33 9600 RELIABLE
? 7200 RELIABLE
11 PROTECTED 30 4800 RELIABLE
28 4000 RELIABLE
27 3200 RELIABLE
10 PROT/UnPROT 23 2400 RELIABLE
5 PROT/UNPROT 22 1200 RELIABLE
1 PROT/UnPROT 20 300 RELIABLE
10 UnPROTECTED 10 2400 NonRELIABLE
9 UnPROTECTED 9 600 NonRELIABLE
5 UnPROTECTED 5 1200 NonRELIABLE
1 UnPROTECTED 1 300 NonRELIABLE
other result codes
7 BUSY 7
6 No DIALTONE 6
4 ERROR 4
3 No CARRIER 3
As you can see by the chart, Hayes does not report protected and unprotected
links by a single result code. They have an extended reporting mode which
allows several codes to be returned identifying the LAP protocol chosen as
well as the speed of the connection. However, this reporting mode has
embedded carriage returns which the Carbon Copy code accepts the first code
returned. This would not pose a problem if the Hayes V-Series had provided
for a command to set a fixed DTE rate.
@DATA_SWITCH [email protected]
There are several considerations for DATA-SWITCHES which direct Carbon Copy
performance. When placing calls in a switch the following behaviors may be
CCHELP CALLING CC
a) Switch requires an extension once connection is established, the
extension number should be placed in the password field of the call
table entry or the call can not be completely automated, this allows
the extension to be reached. Carbon Copy will be waiting for a password
entry. The password prompt screen stating "SENDING PASSWORD TO CC" will
appear; the user should enter his password at this time. If garbage
characters appear in the remote operator's dialogue fox of the "Chat
Screen", meaning illegible dialogue, then the response strings on
the switches side are incorrect. Either more delays are required in the
response strings or the baud rate should change to reflect the correct
CC CALLING CCHELP
b) Possible with version 5.0 of the software. If an extension is required,
then the CC system, from within the CCINSTAL utility can use the phone
number field to contact the CCHELP system. There is one stipulation,
the speed of the CC modem must be exactly the anticipated speed on
the CCHELP side. The CC side will not receive the baud rate connect
message until after the carrier negotiation has been completed. Within
the phone number field of the call table entry, the phone number should
be placed first, followed by the "CARRIER DETECT" symbol. Once the
phone number is dialed through the modem, the software will pause until
the carrier has been established with both modems having generated
connection result codes which the CC side will discard at this point
in the code. Since the CC side will still be performing the dialing
process it will use the result code and it will not be searching for a
match against the connect strings now, follolwing the CARRIER DETECT
symbol should be the extension number which the CCHELP call table's
phone number field should contain next. The modem descriptor's connect
strings are not being checked at this point in the software.