Category : Communication (modem) tools and utilities
Archive : TR3-14.ZIP
Filename : TR.DOC
Output of file : TR.DOC contained in archive : TR3-14.ZIP
1. What TeleReplica Will Do
1.1 TeleReplica will allow you to connect two IBM PC-compatible computers
together (via telephone lines and modems, or via a direct cable, or via a
common mini- or main-frame computer), and arrange for input to be
accepted from either keyboard, and for both displays to appear identical.
In this document the computer which is running normal programs is called
the host computer, and the other computer is called the replica computer,
since its display is a replica of the host computer's display.
1.2 TeleReplica will do a reasonable job of optimizing the screen changes
transmitted, so that (for example) moving a highlighted menu bar will
appear almost immediately even at 1200 bps (provided the call is
relatively local).
1.3 TeleReplica always updates the replica computer's screen to match the
current host screen. This means that if several commands are issued
without waiting for the display to catch up, then the replica screen will
be updated to show the final host screen, without wasting time
transmitting the intermediate screens.
1.4 TeleReplica uses a password of up to 39 characters, which means an
intruder would (on average) take millions of years at 2400 bps to guess a
well chosen password! Since this password is transmitted automatically,
there is no need to keep it short and easy to remember - once TeleReplica
is installed, you will never need to enter the password manually.
1.5 TeleReplica will allow the host site to call the replica site, or the
other way around. For consultants this means you can make your clients
pay the 'phone bills!
1.6 TeleReplica will automatically detect the "baud" rate being used by the
replica computer, and set the host computer's "baud" rate to match. This
means that users with different speed modems can all access a single
host.
1.7 TeleReplica uses less than 10K of memory on the host computer, which
means there should be enough memory left to run most applications.
1.8 TeleReplica can be installed to "type" a command in response to the
'phone ringing, which allows better control than merely using the modem's
auto-answer capability.
1.9 TeleReplica will trap anything printed to any printer on the host PC, and
redirect it to the chosen printer at the replica PC. This redirection
takes place only when a session is active, so at other times the host can
be used to print normally even if TRHOST is still loaded.
1.10 TR is "DESQview-Aware". See Appendix D for details.
1.11 Full source code is available at a small cost. See REGISTER.DOC for
details.
2. What TeleReplica Will NOT Do
2.1 TeleReplica will not replicate graphics displays. If the user at the
replica computer runs a program that displays graphics, then the replica
display may show (textual) garbage. Keystrokes will still be transmitted
to the host computer, but the user must remember which keys are necessary
to get out of graphics mode again! TeleReplica gives a warning that
graphics mode has been entered, but by then it is too late to avoid it.
However, in an emergency TR can instruct the host computer to reboot, so
provided TRHOST is run from AUTOEXEC.BAT this provides a means of
recovery.
2.2 TeleReplica will only replicate text page 0, and only as an 80 column by
25 line display.
2.3 TeleReplica will only work with the standard keyboard buffer (starting at
the address in segment 0040h specified at offset 0080h, ending at the
address specified at offset 0082h, with head pointer stored at offset
001Ah, and tail pointer stored at offset 001Ch).
2.4 Where TeleReplica is being used with a modem, it will work best if the
modem and modem cable provide carrier detect, data terminal ready and
ring indicator signals in addition to the minimum transmit data, receive
data and ground signals.
2.5 TeleReplica will cause bad "snowing" on some older CGA display cards. No
attempt has been made to use the retrace intervals for screen memory
access.
2.6 TeleReplica will slow down the normal operation of the host computer. On
a 4.77MHz PC performance can be halved; on a faster host the difference
will not be so noticeable.
2.7 TeleReplica requires DOS 3.0 or later.
2.8 TeleReplica will not work particularly well on a noisy 'phone line. File
transfers are error-checked, but normal screen updates are not. Normally
this will not be a problem, since a corrupted screen will be obvious to
the user and in any case TR will usually detect the problem and
automatically request a full refresh. However, if errors happen very
frequently then TR can spend all its time continually re-refreshing the
display! Printer capture also is not error-checked, so line noise will
garble the printout.
3. Why Use TeleReplica?
3.1 Access to Local Area Network from Home
TeleReplica will allow you to connect into your office computer from
home. This means you do not need to take all your data files home with
you, and that you do not need to license additional copies of your
software (since your home computer is not running the software, only
replicating the screen of your office computer). If your office computer
is part of a local area network, then you automatically have access to
all the network facilities from home.
We regularly use TeleReplica with such programs as WordPerfect,
WordPerfect Office (especially mail), WordStar, FoxBASE, Lotus-style
spreadsheets, all the Novell NetWare utilities, and our local area
network is regularly backed up after hours via TeleReplica! The only
programs we have come across that could not be used remotely either:
a) used graphics displays (e.g. WordPerfect preview); or
b) took over interrupts needed by TRHOST (e.g. comms programs); or
c) used text pages other than 0 (e.g. Turbo Debugger?)
3.2 Software Support
TeleReplica will allow you to take over your client's computer, so that
you can see what is going wrong. In many cases this will avoid the need
for an expensive trip to the client's site.
For details of these and other applications, see the scenarios in
Appendix A.
4. TeleReplica Host Installation
To install TeleReplica at the host computer, first copy the files:
TRHOSTIN.EXE, TRHOST.EXE, TRPUT.EXE, TRGET.EXE, TRTALK.EXE, TRCHECK.EXE,
TRKEY.EXE and TRDIAL.EXE into a directory (say \TR) on the host computer.
Then enter the command:
TRHOSTIN
Your display should show a menu similar to:
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º TeleReplica Host 3.14 Installation Copyright (c) 1990 Douglas Thomson º
º º
º A. Select serial port (currently COM1) º
º B. Change password (currently "password") º
º C. Change modem initialization string (currently: º
º "\rat &c1 &d2\r") º
º D. Change modem dialing format string (currently: º
º "atdt %s\r") º
º E. Select maximum "baud" rate (currently 2400) º
º F. Use modem CARRIER DETECT signal (currently YES) º
º G. Flow control (currently NONE) º
º H. Generate INT 9 on each key (currently NO) º
º I. Respond to modem RING signal (currently NO) º
º J. Reboot on loss of carrier (currently NO) º
º K. Synchronize "baud" rate (currently YES) º
º L. Send wakeup every 2 minutes (currently NO) º
º M. Create consistent .TR file º
º Q. Abandon changes º
º S. Save changes and leave installation program º
º º
º Selection: º
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Consider each of these options in turn:
4.1 Select Serial Port
Another menu will appear:
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º TeleReplica Host Program Serial Port Selection º
º º
º 0. Completed, no (further) change º
º => 1. COM1 port (base 0x03F8, interrupt 0x0C) º
º 2. COM2 port (base 0x02F8, interrupt 0x0B) º
º 3. COM3 port (base 0x0000, interrupt 0x0C) º
º 4. COM4 port (base 0x0000, interrupt 0x0B) º
º A. Custom base (currently 0x03F8) º
º B. Custom interrupt (currently 0x0C) º
º º
º Selection: º
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All four "standard" ports are listed, although the port addresses for
non-existent ports are unlikely to be meaningful (if you are lucky, they
will be flagged with a base of 0x0000). To select one of these ports,
just type the port number. If you have a non-standard port/interrupt
combination, then use A and B to specify exactly what you want. When you
are happy with the settings, select 0 to return to the main menu.
Please note that I do not have access to any system with COM3 or COM4
installed, so I cannot guarantee the performance of TeleReplica when
these ports are used. Since COM1 and COM3 share the same interrupt, only
one or other of these ports can be in use at the same time (the same
applies to COM2 and COM4).
4.2 Change Password
The string editing menu will appear:
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º TeleReplica Host Program Password Selection º
º º
º Edit existing string: º
º password º
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Whenever you see the "Edit existing string:" prompt, you can use the left
and right arrow keys to move the cursor through the string, and the
backspace and delete keys to delete characters to the left of or under
the cursor respectively. Any normal characters you type will be inserted
at the cursor position.
You will not be able to enter more than the maximum allowed number of
characters for any string.
Since you will only need to enter the password once during installation,
and never in normal use, it is recommended that you make the password
near the maximum length and quite random. The main thing is that no-one
should have any chance of guessing the password.
4.3 Change Modem Initialization String
The string editing menu will appear again, this time asking for the modem
initialization string. This string is transmitted to the modem at the
maximum "baud" rate when TRHOST runs for the first time. If you are using
an automatic power switch that powers up the host computer when the
'phone starts ringing, then the initialization string may need to answer
the 'phone (see scenario A2). There may also be various operating modes
that cannot be stored permanently in your modem's non-volatile memory,
and which must therefore be established each time TRHOST starts. In many
applications, where nothing needs to be changed, this string may be
empty.
You will probably need to refer to the instruction manual for the host
modem to work out what if anything is required.
As well as normal characters, you may need to include some special
characters such as carriage return. Carriage return can be encoded as \r
(see the main menu at the start of section 4). Alternatively, any
character can be entered in hexadecimal as \0x followed by two hex digits
(for example, the escape key is \0x1B).
It may also be necessary to include some kind of delay. For example, some
modems go off into a world of their own for a second or so after a reset
command. Delays are entered in milliseconds as \D followed by the delay
(for example, \D1000. [1 second] or \D500. [half a second]). Delays are
only accurate to the nearest 1/18.2th of a second, so the number you
enter may be modified slightly to reflect the nearest possible actual
delay.
4.4 Change Modem Dialing Format String
This string determines what TRDIAL will send to the modem to dial a
number. The usual use of TRDIAL will be something like TRDIAL 221166, so
normally the dialing format string should contain a %s to insert the
number. For example, if the dialing string is "atdt %s\r" and the user
enters the previous dialing command, then what will be sent to the modem
is "atdt 221166\r".
Alternatively, if only one number is required, then the dialing format
string may contain the actual number, in which case the user will only
need to enter TRDIAL by itself.
Note that (when CARRIER DETECT is being used) TRDIAL will only send
anything to the modem if there is NO carrier detected - once a carrier
had been established the modem would not act on the command in any case,
but would send it through to the other end. When TRHOST is installed to
ignore CARRIER DETECT, TRDIAL will send data to the modem regardless.
4.5 Select Maximum "Baud" Rate
Another window will appear:
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º TeleReplica Host Program Maximum "Baud" Rate Selection º
º º
º Enter "baud" rate: º
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You should enter the maximum "baud" rate that the host modem is capable
of using. Usually this will be 1200, 2400 or 9600. Note that TRHOST can
automatically adjust to half this speed, a quarter of this speed, or one
eighth of this speed. Thus if you choose 2400 bps, TRHOST will be able to
work at 2400, 1200, 600 or 300 bps (provided the host modem can handle
these speeds).
If you will be using a direct cable between two PCs, then 19200 should
work on all systems and 38400 will work on faster computers. If your
computers have NS16550AFN UART chips instead of the standard 8250 chips
then you may find speeds of 57600 or even 115200 work even on slower PCs
(not tested, I only have the 8250!).
4.6 Use modem CARRIER DETECT signal
Selecting this option will toggle between using and not using the carrier
detect signal provided by the modem. If you are using a real modem, then
you should set this to YES and make sure the modem is initialized so that
it reports the true CD status from the 'phone line.
If you are using a direct cable between two PCs, or connecting PCs via a
mini-computer, then set this option to NO.
4.7 Flow control
Selecting this option will bring up the following menu:
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º TeleReplica Host Program Flow Control Selection º
º º
º 0. Completed, no (further) change º
º => 1. No flow control º
º 2. Hardware (RTS/CTS) flow control º
º 3. Software (XON/XOFF) flow control º
º 4. Both hardware and software flow control º
º 5. Set inter-character gap time (currently 330 ms) º
º º
º Selection: º
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4.7.1 TeleReplica can use the following flow control systems:
NONE No flow control. Use this with a direct cable or with
modems that require no speed adjustment.
CTS Hardware flow control using RTS (request to send) and
CTS (clear to send). Use this in preference to software flow control if
it is available.
XON Software flow control using XON and XOFF (^S/^Q). Use
this if flow control is needed and hardware flow control is not
available.
BOTH Use both software and hardware flow control. I can't
imagine why anyone would want this...
4.7.2 Normally TeleReplica will not need to use any flow control even when it
is available. However, some modems communicate with the PC at a different
speed than that at which they communicate with other modems, so that it
is possible for the PC to "get ahead" of the modem and hence lose data.
In these cases it is necessary for the modem to tell the PC when to wait
a bit before sending the next byte.
4.7.3 A side effect of software flow control is that TeleReplica will not use
ANY control characters: it will not send any, and it will ignore all
control characters received apart from XON and XOFF. This may be useful
for networks that respond to certain control characters; however, binary
file transfers will be slightly slower since 64 characters (control
characters with and without the parity bit) are not used. Note that both
TR and TRHOST must therefore either use or not use software flow control
- if one end uses software flow control and the other does not, then no
communication will be possible!
4.7.4 When TRHOST is receiving characters (normally keys that have been pressed
at the remote PC - each key is encoded as two or three characters) it
waits a certain length of time after receiving the first character before
giving up and ignoring the key. This is important, since otherwise a
single byte introduced by noise on the line could cause all subsequent
keys to be misinterpreted (the second character of one key being treated
as the first character in the next key and so on). TR always sends all
the characters which constitute one key as close together as the
communication speed will allow, so usually a gap of even 0.1 seconds
means that something has gone wrong and that TRHOST should start looking
for a new key again. However, if the link between TR and TRHOST uses
packets, or for any other reason introduces significant gaps between two
characters that were sent together, then TRHOST may need to be adjusted
to tolerate longer gaps between characters which should be together.
Selecting option 5 will bring up the following screen:
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º TeleReplica Host Program Inter-character Gap Time Selection º
º º
º Longest gap to be tolerated (ms): 330 º
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Any time up to about 10 seconds (10000 ms) can be entered. Be aware that
if this time is set to 10 seconds, and line noise does introduce a stray
character, then you will need to wait 10 seconds without typing anything
at the remote PC to get TRHOST back into synchronization!
4.8 Generate INT 9 on each key
When TRHOST receives a key from TR, it will usually just place it in the
keyboard buffer to be found by any program that wants to read a key.
However, some applications monitor the keyboard interrupt (INT 9) and
only read the keyboard input buffer after there has been a keyboard
interrupt! To keep such programs happy, TRHOST can generate an INT 9
after it has placed a key into the buffer. However, this can cause
problems for other programs, particularly when the host and remote
keyboards may both be in use at the same time (e.g. TRTALK). Leave this
option OFF unless it is really necessary.
4.9 Respond to modem RING signal
Selecting this option will toggle between responding to and ignoring the
RING signal which the modem provides to tell the PC that the 'phone is
ringing. If this option is turned on, then the menu will be extended with
the following sub-options:
G. Respond to modem RING signal (currently YES)ÄÄÄÂÄ 1. too short 220 ms
ÃÄ 2. too long 5000 ms
ÃÄ 3. delay 10000 ms
ÃÄ 4. reset 10000 ms
ÀÄ 5. response Ä¿
"\0x1Btrauto\r"
4.9.1 If the 'phone only rings for a very short time, you may wish to ignore
the ringing completely - otherwise just knocking the 'phone off the hook
can trigger a TRHOST response!
4.9.2 If the 'phone rings for a long time, then this may indicate that the
caller is a person who should not be greeted by an ear full of modem! If
TRHOST is intended to respond before the 'phone stops ringing, then this
time should be set the same as the delay below.
4.9.3 After a certain length of time (measured from when the 'phone starts
ringing) TR will check that the amount of ringing was within the
specified range, and if so, will "type" the response string (see point
5).
4.9.4 If the 'phone rang for too long, then TR must know when to start looking
for another call. If the 'phone has not rung for a certain length of time
then TR assumes any ringing must be a new call.
4.9.5 You may specify a response of up to 39 characters. If you expect the host
PC to be at the DOS prompt when a call comes in, then it is a good idea
to start with an escape key, so that DOS discards anything already typed
and treats what follows as a new command. Typically the command will be
the name of a batch file which can then do whatever is desired with no
length limit.
If all this sounds too complicated, but you still think you want to
enable ring response, then have a look at the configuration scenario
called "Home/Office via Modem" in section A5.
4.10 Reboot on loss of carrier
Selecting this option will determine whether or not the computer will
reboot when the modem reports that the carrier has been lost (presumably
because the other end hung up). See scenario A5 for an example of an
application taking advantage of this feature.
4.11 Synchronize "baud" rate
Selecting this option will determine whether or not TRHOST will attempt
to match the "baud" rate being used by TR at the other end. This is
useful if several users will all dial into the same host, but some users
have slower modems than others. See scenario A2 for an example of this.
4.12 Send wakeup every 2 minutes
Selecting this option will determine whether or not TRHOST will send a
NULL character whenever two minutes has passed with no other activity. A
single NULL is ignored by TR, but may serve to keep a connection to a
mini-computer link. See scenario A4 for an example of this.
4.13 Create consistent .TR file
Once TRHOST has been installed correctly, TRHOSTIN can create a
configuration file for TR that is consistent (same "baud" rate, password,
use of carrier detect etc). It will normally still be necessary to edit
this file to do some fine tuning, but the work required will be less than
if you started with the vanilla TR.TR file distributed with TR.
4.14 Abandon Changes
If you have made a mistake, or if you only wanted to see what the current
settings were, then this option allows you to quit without making any
changes.
4.15 Save Changes and Leave Installation Program
This is the normal way to exit this program when you have made all the
required changes. The relevant files (TRHOST.EXE, TRGET.EXE, TRPUT.EXE
TRTALK.EXE and TRDIAL.EXE) will all be modified appropriately.
Note that the executable files are actually modified, so beware of virus
protection programs which compute checksums for executable files - they
are likely to report possible virus infections after installation! The
alternative (loading configuration information from a disk file) was
rejected due to the additional memory required for the file processing
code...
5. Replica Installation
To install TeleReplica at the replica computer, first copy the files:
TR.EXE, TR.HLP, and TR.TR (or better still the .TR file that was created
during host installation) into a directory (say \TR). Then use a text
editor to edit the .TR file. This file should look something like:
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TeleReplica Configuration File
Do NOT change the order of these parameters, or delete any lines!
"COM1" Communications port ("COMn" or base/interrupt)
2400 "Baud" rate (typically 300, 1200, 2400, or 9600)
"COMSPEC" Pathname for DOS Command Interpreter (or "COMSPEC")
07 Attribute for normal text (such as help screen)
47/70 Attribute for file transfer monitoring
4F/0F Attribute for pop-up windows
"trput %s\r" Host command to send (download) files
"trget\r" Host command to receive (upload) files
0 Printer (normally 0, 1 or 2)
440 Frequency of "bell" tone (Hz)
100 Duration of "bell" tone (ms)
256 Block size for file upload (1-256)
8 Number of block buffers for upload (1-8)
111 Length of "break" (ms)
3000 Time to wait for first char before timeout (ms)
500 Time to wait for subsequent chars in block (ms)
56 Time to wait between "typing" keys (ms)
"password" Password to log in to host computer
"MODEM" Type of link (MODEM, DIRECT, or OTHER)
"NONE" Flow control (CTS, XON, BOTH or NONE)
"YES" Send BREAKs to host computer
"YES" Use BIOS for keyboard input
"[TR] %s" DOS shell prompt format string
"LRCA" Local command shifts (Left, Right, Ctrl, Alt)
"" Connect command for modem
"" Disconnect command for modem
Each of the remaining lines must contain 3 strings and a number.
The first string is the trigger string to search for.
The second string is the response to be sent after the trigger.
The third string is the response to be sent after timeout.
The number is the time to wait before timeout (in ms).
ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ
Most of these parameters will not need to be changed.
5.1 The serial port may be one of the standard ones ("COM1", "COM2", "COM3",
or "COM4") or you may specify the base address and interrupt number [e.g.
COM1 would be 03F8/0C].
5.2 The "baud" rate should be set appropriately for the modem.
5.3 The DOS command interpreter should normally be taken from the COMSPEC
environment variable. However, if this does not work (or does not select
the desired command interpreter) the full path name of a command
interpreter can be specified (e.g. "C:/DOS/COMMAND.COM" - or
"C:\\DOS\\COMMAND.COM" - the \\ is needed since \ introduces an escape
sequence).
5.4 Video attributes are two hexadecimal digits: the first is the background
color, and the second is the foreground color. Optionally a second
attribute may be specified (e.g. 4F/70) - the first attribute is used for
color displays and the second is used for monochrome systems (this allows
a single control file to work without change with different displays).
5.5 When the user running TR requests a file transfer, TR "types" the
necessary command at the host PC. These two lines should not be changed
except possibly to fill in a full path name if TRGET.EXE and TRPUT.EXE
are not in the path of the host PC.
5.6 When host printing is being redirected to the replica computer's printer,
TR needs to know which printer to use. LPT1: is printer 0, LPT2: is
printer 1, and LPT3: is printer 2. Serial printers are not directly
supported.
Note that it is not necessary or possible to specify which host printer
is to be redirected; anything sent to LPT1:, LPT2: or LPT3: will be
redirected. This was done to save the user the trouble of working out
which printer the host was using.
5.7 The frequency (or pitch) and the duration of the "bell" can be modified
to suit your personal preferences (and the volume of your PC's speaker!).
The "bell" is used to indicate that some corruption of the data being
received by TR has occurred.
5.8 The size of file transfer blocks and the number of buffers should not
need to be changed, except on a very poor 'phone line (in which case
smaller blocks and fewer buffers may improve matters).
5.9 The length of "break" required is not likely to need to be changed -
unless perhaps a mini-computer requires longer?
5.10 Once the file transfer has begun, TR will wait a certain time for the
start of each block. If nothing has been received within the time, then
TR will request the block be sent again (since presumably it got lost).
5.11 Once the first character in a block has been received, the rest should
follow immediately - any gap probably means problems. However, when using
an overloaded mini-computer link (or using a packet network that may
introduce delays between packets) this parameter could need to be longer.
5.12 Since on many PCs (especially ones with CGA displays) interrupts are
disabled for LONG periods when writing to the screen, it is usually
necessary to make TR pretend to type quite slowly, especially when
sending things like file transfer commands. If you find you are losing
characters under these circumstances, then make this delay longer; if you
have a smart BIOS and/or version of DOS and/or command interpreter then
you may be able to get away with a shorter delay (even 0 ms). On all the
systems I have used, the time taken to send two characters at 2400 bps or
below is sufficient, so this delay is probably only needed above 2400
bps.
5.13 The password must match the password installed in TRHOST at the host
computer.
5.14 There are three kinds of link that may be used between two PCs:
MODEM Use this if you are working with a modem that provides CARRIER
DETECT (note that you will require an appropriate cable [see
Appendix C1] and possibly some initialization of the modem [see
the start of Appendix A]).
You can also use this if you are using a null modem cable that
provides a CD line (see Appendix C3).
DIRECT Use this if you are working with a three-wire null modem cable,
or if you are using a modem/cable that cannot provide accurate
CD information.
OTHER Use this if you are working with a mini-computer link (see
scenario A4), or for initial modem setup (see the start of
Appendix A).
5.15 TR can use the following flow control systems:
NONE No flow control. Use this with a direct cable or with modems
that require no speed adjustment.
CTS Hardware flow control using RTS (request to send) and CTS (clear
to send). Use this in preference to software flow control if it
is available.
XON Software flow control using XON and XOFF (^S/^Q). Use this if
flow control is needed and hardware flow control is not
available.
BOTH Use both software and hardware flow control.
See the discussion of flow control under host installation for further
details.
5.16 Normally TR should send BREAKs to TRHOST, but see scenario A4 for use
with a mini-computer link.
5.17 Normally TR will use the BIOS for keyboard input. However, many BIOSes
filter out keys from enhanced keyboards (e.g.
keys is important then it may be necessary to NOT use the BIOS, but
rather to use the keyboard input buffer directly. Note however that some
keyboard enhancing programs (such as Newkey) will only work with the BIOS
setting. This is because they intercept the keyboard interrupt and store
keys away in some place other than the standard buffer area, so that TR
cannot find them!
5.18 The DOS prompt for when you are in a TR shell can be edited to suit your
individual preferences - the %s inserts the original prompt.
5.19 If you don't like the default
combination to access local commands in TR, then you can change this to
any other combination of these four main shift keys ("CAL" would mean
this).
5.20 The connect command for the modem is sent when TR starts running (this
will often be a dial command). The modem command strings here have the
same format as those described above for the host computer installation
(with the addition of a \B escape sequence that causes TR to transmit a
BREAK). Make sure you leave the double quotes (") around each string!
5.21 The disconnect command is sent when TR terminates (using exit option 3
only).
5.22 The automatic response strings at the end of the file can be used to
respond to modem status messages. For example, if the replica computer's
modem is not set to auto-answer, then TR may need to respond to a "RING"
message from the modem by answering the 'phone - see scenario A5 for an
application. These strings can also be used to achieve an automatic login
to a mini-computer - see scenario A4 for an example. The trigger strings
are only active before a TR-TRHOST link is established. They are also
disabled once the final trigger string has been detected.
Please note that since this file contains the password, anyone who
obtains a copy of this file can potentially access the host computer!
6. How to Use TeleReplica
The following instructions assume that TeleReplica has been correctly
installed (see sections 4 and 5). Only general guidelines are given here;
more details are provided in the scenarios in Appendix A.
6.1 Host Computer
First run the TRHOST program. If the replica computer is to originate the
'phone call, then this may be all that is necessary.
If the host computer is to originate the call, then use the command:
TRDIAL
or
TRDIAL number
depending on how the dialing format string was installed.
Once TRHOST is resident and the call is established, the host computer
can be used normally. The only difference is that everything that appears
on the screen is also being replicated on the replica computer's screen.
The best way to remove TRHOST from memory is to run TRREMOVE. It is also
possible to use utilities such as marknet/relnet. Note that some common
mark/release utilities can NOT be used, because they do not restore the
interrupt mask register.
6.2 Replica Computer
Use the command:
TR [use TR.TR configuration file]
or
TR filename [use filename.TR configuration file]
If the replica computer was to originate the call, then the modem
initialization string in the configuration file will usually include a
dial command to call the host computer.
If the host computer was to originate the call, then the initialization
string may contain an answer 'phone command. Note that in this case it is
important that the TR program not be run until after the 'phone starts
ringing! (Alternatively, there may be no initialization string, but
instead there may be a trigger string to respond to RING from the modem -
see scenario A5.)
If the configuration file contains no modem initialization string, then
the user at the remote computer can enter modem commands manually. This
may be convenient for a consultant wishing to dial many different
clients. (Before a carrier is detected, TR will behave much like a normal
communications program.)
Once both TR and TRHOST are running and connected to each other, they
will automatically adjust the host computer's "baud" rate (if this
feature is enabled) and the host computer will check the password
provided by the replica computer. Provided the password is correct, the
replica computer will effectively be able to take over the host computer,
or alternatively to observe whatever the host computer is doing. Any key
typed on the replica computer will be acted upon by the host computer,
and anything that appears on the host computer's screen will also appear
on the replica computer's screen.
It is sometimes necessary to execute a command on the replica computer,
rather than transmitting the keystroke to the host computer. This is
achieved by holding down some combination of left shift, right shift,
ctrl and alt all at the same time (the exact combination is specified in
the .TR file currently in use). When you do this a list of all the
possible commands will be displayed, and you can then type the required
command key:
F2 simulate a carrier signal (useful if the modem does not provide
this information) [link type should be OTHER to use this command]
Ctrl-F2 simulate NO carrier signal (opposite of F2)
F6 send break, restart session [use this if TeleReplica locks up -
very rare!]
F8 reboot the host computer (useful if host computer "hangs" for any
reason, but make sure TRHOST is run from AUTOEXEC.BAT!)
F9 shell directly to DOS, return to TR later by typing "exit"
F10 exit TeleReplica [optionally shell out and return later]
Home refresh display from HOST [use this if a bad 'phone line messes
up the screen]
PgUp upload file using DMP protocol [transfer file(s) from replica to
host]
PgDn download file using DMP protocol [transfer file(s) from host to
replica]
Note that before performing a file transfer, the host computer must be at
the DOS prompt, and TRGET.EXE and TRPUT.EXE must be accessible in the
current path (or alternatively the .TR file must contain full paths, not
just (say) TRGET but rather C:/TR/TRGET - note forward slashes!). If
TRGET/TRPUT cannot be found, then the host will display a "command not
found" error message, but TR will go on waiting for a response from
TRGET/TRPUT! Pressing any key will terminate this waiting and bring up an
appropriate error message.
If a file transfer needs to access a file in another directory, it may be
convenient to shell out of TR, change directories, and then exit from DOS
back into TR to start the file transfer. TR will transmit any path that
you specify, so if the two PC's have equivalent directory structures it
is easy to transfer files to the corresponding directory on the other PC
(see Appendix B for a sample file transfer session).
7. TeleReplica Utility Programs
7.1 TRREMOVE
This will search for a copy of TRHOST loaded in memory. If one is found,
then it is checked to see whether it is currently in use (if so, TRREMOVE
will ask for confirmation before removing it). If it is not in use, or if
it is to be removed anyway, all interrupts, the interrupt mask register
and the serial chip state are restored to their initial state when TRHOST
started running, and TRHOST's memory is freed.
Please note that as with most TSR programs, this may not work unless
TRHOST was the most recent TSR to be loaded. In general TSR programs
should be unloaded in the reverse order they were loaded. In this case
"not working" means that any TSR loaded after TRHOST may cease to
function. If this is not possible then the use of marknet/relnet (or some
other mark/release utility that preserves the interrupt mask register as
well as the vectors) is recommended.
It is sometimes convenient to be able to keep a modem connection even
though TRHOST is being unloaded. Normally, TRREMOVE will restore the
serial port state to its original state when TRHOST was first run.
However, it is possible to force the DTR line to be left active by
entering:
TRREMOVE ON
and DTR can be forced off by entering:
TRREMOVE OFF
7.2 TRTALK
TRTALK will allow the users at the host and replica computers to "talk"
to each other. Anything that is typed at the host computer is displayed
in the top half of the screen, and anything that is typed at the replica
computer is displayed in the bottom half of the screen.
TRTALK sends a special command to TR to tell TR that talk mode is
required, so that TR will send keys in a way that can be distinguished
from the host keys. If this command is lost, then what is typed at either
end will appear in the top window! If this happens, simply exit TRTALK
(Alt-X) and run it again.
TRTALK also sends a special command to TR to tell TR to end talk mode. If
this command is lost, then TR will behave normally unless a program that
uses shift-key status is run, which will cause problems because in talk
mode TR does not send shift status information! To correct this problem,
use local TR command
command is to end talk mode.
7.3 TRCHECK
TRCHECK checks to see if the current time is within a specified range,
and returns the DOS errorlevel set to 0 if within the range and 1 if
outside the range. The following code might appear in an AUTOEXEC.BAT
file on a host computer:
trcheck 9:00:00 17:00:00
if not errorlevel 1 goto done
trhost
:done
The effect of this is to first check to see if the time is between 9AM
and 5PM. If so, then errorlevel is set to 0, and nothing further happens.
However, if the time is not between 9 and 5, then trhost will be run.
This has proved valuable when TRHOST must run on an office computer
outside normal working hours, but the computer must be used normally
during the day. See also scenario A5 for a further application.
7.4 TRKEY
TRKEY checks to see if a key has been pressed. This is useful when a
computer will usually be used as a TeleReplica host, but sometimes must
be used locally. Rather than having to boot from a different disk, the
following code might appear in an AUTOEXEC.BAT file on a host computer:
trkey
if errorlevel 1 goto done
trhost
:done
The effect of this is to run TRHOST only if no key has been pressed. If a
user is at the computer and presses a key then TRHOST will not be loaded.
See scenario A5 for an example of this.
7.5 TRLOCK
TRLOCK locks the keyboard of the host PC, so that it cannot be operated
locally without rebooting. It was written at the request of a LAN manager
who wished to use TeleReplica to do system maintenance, but did not like
the idea of a publicly accessible PC being logged in as SUPERVISOR! The
usual sequence would be to first run TRLOCK, then log in as SUPERVISOR.
This will not stop someone watching the screen of the host PC, but it
will prevent them from doing anything...
Source code is provided, and TRLOCK is released public domain.
APPENDIX A - Configuration Scenarios
The following are specific situations in which TeleReplica has been used.
The descriptions of the situations, and the resulting configurations of
TeleReplica, are presented in detail. It is hoped that seeing the way
TeleReplica was installed in some typical applications will help when it
comes to installing TR for your own situation.
Note that unless otherwise stated, all modems are assumed initially to be
in the TeleReplica default state, to be connected to the PC via a 25-way
straight-through modem cable, and to be Hayes-AT-command-compatible. To
get a Hayes-AT-command-compatible modem into the TeleReplica default
state the following commands should be sent to the modem using any normal
communications program (or using TR SETUP):
at &f restore modem to "factory default"
at &c1 modem should report true carrier status
at &d2 modem should take notice of DTR to hang up 'phone
at x4 (optional) give detailed status messages etc
at &w save current state for future use (the state is saved
in non-volatile RAM, so that this setup only needs to
be done once unless some other program interferes)
A1. Consultant/Client via Modem
A1.1 Here the consultant is running a 2400 bps modem connected to COM1, and
the client (whom we will call Fred) is running a similar modem also
connected to COM1. Both computers are equipped with EGA color display
cards. The consultant will be performing the TRHOST installation for the
client, and then sending the client the installed version ready to run.
When the client wants help, he will call the consultant (a normal voice
call). When both parties are ready TeleReplica must take over the call.
A1.2 First the consultant must run TRHOSTIN, and make the changes necessary to
achieve the following display:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host 3.14 Installation Copyright (c) 1990 Douglas Thomson º
º º
º A. Select serial port (currently COM1) º
º B. Change password (currently "Fred's password") º
º C. Change modem initialization string (currently: º
º "") º
º D. Change modem dialing format string (currently: º
º "ata\r") º
º E. Select maximum "baud" rate (currently 2400) º
º F. Use modem CARRIER DETECT signal (currently YES) º
º G. Flow control (currently NONE) º
º H. Generate INT 9 on each key (currently NO) º
º I. Respond to modem RING signal (currently NO) º
º J. Reboot on loss of carrier (currently NO) º
º K. Synchronize "baud" rate (currently YES) º
º L. Send wakeup every 2 minutes (currently NO) º
º M. Create consistent .TR file º
º Q. Abandon changes º
º S. Save changes and leave installation program º
º º
º Selection: º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Refer to section 4 for the meaning of each option. Since both modems run
at the same speed it does not matter whether "baud" rates get
synchronized or not. Since Fred will only run TRHOST when he wishes to
get help from the consultant, the password is not important. The modem
dialing format string simply answers the 'phone - or more accurately,
since the 'phone will already be in use for the voice call, it causes the
modem to take over the call in "answer" mode.
Next the consultant selects option M from the main menu, and enters the
name of the configuration file he wishes to use for Fred:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host Program .TR File Name Selection º
º º
º Edit existing string: º
º fred º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Finally the consultant exits TRHOSTIN by selecting option S to save the
changes. The consultant can now send Fred a disk with all the installed
TeleReplica files on it (note that the consultant should also send Fred
an unaltered original copy of the TeleReplica files in case Fred wants to
pass them on to anyone - see the LICENCE.DOC file for details).
A1.3 Now the consultant needs to edit the file named FRED.TR to make a few
alterations (TRHOSTIN only provides a starting point...). In particular,
the following line must be changed:
"" Connect command for modem
to:
"at d\r" Connect command for modem
This command tells the modem to go "off hook" and take over the call in
"originate" mode.
This completes the installation stage.
A1.4 When Fred wants some help, he will run TRHOST and then 'phone the
consultant and explain the problem. When the consultant is ready, he will
enter the command:
TR FRED
and then instruct Fred to enter the command:
TRDIAL
and hang up the 'phone as soon as he (Fred) hears his modem making a
"screaming" noise. After giving these instructions (and thus while Fred
is still typing) the consultant will hang up his 'phone. Fred will finish
entering the TRDIAL command, and hang up when he hears the screaming
noise. TeleReplica will then take over the call, synchronize "baud"
rates, exchange passwords, and give the consultant control of Fred's
computer.
A1.5 When the consultant is finished, he will exit TR using option 3, which
will cause the modem to hang up and terminate the 'phone call.
Fred can either leave TRHOST running (it will do no harm, and uses only
9K of memory), or else use TRREMOVE to uninstall TRHOST.
A2. Remote/Shared via Modem
A2.1 Here a remote user wishes to connect into a local area network, and one
node in the LAN is dedicated to this purpose. The main problem is that
since the LAN node will be unattended, all it takes is one user to run a
program which "hangs" the computer, and then no-one will be able to dial
in until someone pushes the reset button on the node PC! However, in this
scenario there is a modem-controlled switch box which turns on power to
the node PC as soon as the 'phone starts ringing, and leaves the power on
until either a minute or so has elapsed with no carrier being
established, or until the carrier is lost (which will happen when the
remote user hangs up). [These switch boxes are (I believe) commercially
available, and indeed the electronics required is trivial to someone who
feels at home with circuit diagrams and a soldering iron. We have several
home-made ones in use here at MUCG.] This means there is no problem if a
user "hangs" the computer; just hang up and then dial in again, and the
computer will have been powered down and come up again clean!
The node PC has a 2400 bps modem connected to COM2, and the remote user
is running a 1200 bps modem connected to COM1. The node PC is equipped
with a CGA color display card (with no monitor required). The remote PC
is equipped with a Hercules monochrome display.
The LAN manager will be performing the TRHOST installation for the node
PC, and then providing all the remote users with a disk that is almost
ready to go.
The 'phone number of the node PC is 123 4567.
A2.2 First the LAN manager must run TRHOSTIN, and make the changes necessary
to achieve something like the following display:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host 3.14 Installation Copyright (c) 1990 Douglas Thomson º
º º
º A. Select serial port (currently COM2) º
º B. Change password (currently "sdggsdjgxvwept97867km,.mvikjdsdh") º
º C. Change modem initialization string (currently: º
º "\rata\r") º
º D. Change modem dialing format string (currently: º
º "\r%s\r") º
º E. Select maximum "baud" rate (currently 2400) º
º F. Use modem CARRIER DETECT signal (currently YES) º
º G. Flow control (currently NONE) º
º H. Generate INT 9 on each key (currently NO) º
º I. Respond to modem RING signal (currently NO) º
º J. Reboot on loss of carrier (currently NO) º
º K. Synchronize "baud" rate (currently YES) º
º L. Send wakeup every 2 minutes (currently NO) º
º M. Create consistent .TR file º
º Q. Abandon changes º
º S. Save changes and leave installation program º
º º
º Selection: º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Refer to section 4 for the meaning of each option. Note that the modem
initialization string answers the 'phone - this is nice in the case of
timed call charges, since the remote user does not pay for the time it
takes the PC to boot. Since some remote users will dial in at 2400 bps,
TRHOST must be installed for 2400; but since other remote users will dial
in at 1200 bps it is essential that "baud" rates get synchronized. Since
anyone could try to get into the LAN via the node PC the password is very
important - notice that it is both long and quite random.
Next the LAN manager selects option M from the main menu, and enters the
name of the configuration file he wishes to use for the node PC:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host Program .TR File Name Selection º
º º
º Edit existing string: º
º lan1 º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Finally the LAN manager exits TRHOSTIN by selecting option S to save the
changes. He can now make up a disk with all the installed TeleReplica
files on it to give to the remote users, but first he must edit the
LAN1.TR file to install the node PC's 'phone number. This means changing
the line:
"" Connect command for modem
to:
"at d 123 4567\r" Connect command for modem
so that when remote users run TR the number will be dialed automatically.
Also, since modems more often use COM1 than COM2, the LAN manager should
probably edit the line:
"COM2" Communications port (COMn or base/interrupt)
to become:
"COM1" Communications port (COMn or base/interrupt)
A2.3 Now the remote user needs to edit his personal copy of the file named
LAN1.TR to work at 1200 bps. The line containing:
2400 "Baud" rate (typically 300, 1200, 2400, or 9600)
must be changed to:
1200 "Baud" rate (typically 300, 1200, 2400, or 9600)
This completes the installation stage.
A2.4 When the remote user wishes to connect into the LAN, he will enter the
command:
TR LAN1
This will cause the modem to dial the node PC, which will cause the modem
switch box to turn on the power to the node PC, which will boot and then
run TRHOST, which will make the node PC's modem answer the call.
TeleReplica will then synchronize "baud" rates, exchange passwords, and
give the remote user control of the node PC.
A2.5 When the remote user is finished, he will exit TR using option 3, which
will cause the modem to hang up and terminate the 'phone call. The node
PC will then be powered down until the next call.
A3. Laptop/Desktop via Direct Cable
A3.1 Here someone wishes to connect a laptop computer to a desktop computer
via a three-wire null modem cable. The reason for this is that the
desktop only has a 5.25" disk, and the laptop only has a 3.5" disk, and
it is necessary to transfer files between the two systems. The desktop
computer is a 20MHz 80386, and the laptop is a 12MHz 80286. The cable is
connected from COM1 on the desktop to COM1 on the laptop. The desktop has
a VGA color display; the laptop has a gas plasma display that emulates
EGA.
It does not matter which PC is the host, but for the sake of this example
we will assume the desk PC will be the host.
The laptop computer has its
user does not wish to be using
of accidentally rebooting the computer.
safer combination.
A3.2 First the user must run TRHOSTIN, and make the changes necessary to
achieve something like the following display:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host 3.14 Installation Copyright (c) 1990 Douglas Thomson º
º º
º A. Select serial port (currently COM1) º
º B. Change password (currently "password") º
º C. Change modem initialization string (currently: º
º "") º
º D. Change modem dialing format string (currently: º
º "") º
º E. Select maximum "baud" rate (currently 38400) º
º F. Use modem CARRIER DETECT signal (currently NO) º
º G. Flow control (currently NONE) º
º H. Generate INT 9 on each key (currently NO) º
º I. Respond to modem RING signal (currently NO) º
º J. Reboot on loss of carrier (currently NO) º
º K. Synchronize "baud" rate (currently NO) º
º L. Send wakeup every 2 minutes (currently NO) º
º M. Create consistent .TR file º
º Q. Abandon changes º
º S. Save changes and leave installation program º
º º
º Selection: º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Refer to section 4 for the meaning of each option. Notice that the "baud"
rate is set to 38400 for fast file transfers (this works well on my test
system, but slower speeds may be needed on other systems - experiment!).
Obviously here the password is not important. Since the three-wire cable
will not provide any carrier information, it is essential that carrier be
ignored.
Next the user selects option M from the main menu, and enters the name of
the configuration file he wishes to use for the desktop:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host Program .TR File Name Selection º
º º
º Edit existing string: º
º desk º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Finally the user exits TRHOSTIN by selecting option S to save the
changes.
A3.3 Next the user needs to edit the file named DESK.TR to use the shift key
combination required for the laptop. The line containing:
"LRCA" Local command shifts (Left, Right, Ctrl, Alt)
must be changed to:
"LCA" Local command shifts (Left, not Right, Ctrl, Alt)
The user can now copy the installed files onto a 5.25" floppy disk, take
the disk to a computer that has both 5.25" and 3.5" inch drives, and copy
the file onto a 3.5" disk for the laptop.
This completes the installation stage.
A3.4 When the user wishes to connect the two computers, he will enter the
command:
TRHOST
on the desktop, and the command:
TR DESK
on the laptop. This will cause TeleReplica to synchronize "baud" rates,
exchange passwords, and give the user control of the desktop computer
from the laptop. Files can now be transferred at almost 3.8K per second!
A3.5 When the user is finished, he will exit TR using option 3, which will
take the laptop back to normal, but leave TRHOST in the desktop's memory
(see A1.5 for further discussion of this).
A4. Remote/Shared via Common Mini-computer
A4.1 Here a remote user wishes to connect into a local area network, and one
node in the LAN is dedicated to this purpose. There is no direct link
between the PCs; instead, both the node PC and the remote user must log
into the same mini-computer and run a link program (such as trfifo) to
establish a connection via the mini-computer.
One problem is that since the LAN node will be unattended, all it takes
is one user to run a program which "hangs" the computer, and then no more
remote users will be able to connect to the LAN until someone pushes the
reset button on the node PC! (Note that TeleReplica does support
rebooting the host PC, but this can only work if interrupts are not
disabled and if the relevant code has not been overwritten. As a rule,
TeleReplica can get out of any situation that
out of, but if the hardware reset button was needed TR would be
helpless.)
Another potential problem is that if one user exits TR while still logged
in to the LAN, then the next user could pick up the session! This is
avoided by having the link program send a "reboot" command to the node PC
when the link is broken.
Trfifo cannot pass BREAKs from one end to the other; instead, BREAK is
used to terminate the execution of trfifo. This means that TR must not
send a BREAK unless it wants to kill the link.
To make life complicated, the mini-computer will automatically disconnect
any terminal that does no input or output for 5 minutes. However, the
node PC must remain connected to the mini-computer all day waiting for
remote users to connect in.
The mini-computer links are set at 9600 bps, and cannot be changed. Both
computers are connected to the mini-computer via COM1, and both computers
are running color displays (however, the dedicated node PC requires no
monitor).
The LAN manager will be performing the TRHOST installation for the node
PC, and then providing all the remote users with a disk that is almost
ready to go.
A4.2 First the LAN manager must run TRHOSTIN, and make the changes necessary
to achieve something like the following display:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host 3.14 Installation Copyright (c) 1990 Douglas Thomson º
º º
º A. Select serial port (currently COM1) º
º B. Change password (currently "sdfddffgjkiou774htgjhgsduh875sdh") º
º C. Change modem initialization string (currently: º
º "") º
º D. Change modem dialing format string (currently: º
º "") º
º E. Select maximum "baud" rate (currently 9600) º
º F. Use modem CARRIER DETECT signal (currently NO) º
º G. Flow control (currently NONE) º
º H. Generate INT 9 on each key (currently NO) º
º I. Respond to modem RING signal (currently NO) º
º J. Reboot on loss of carrier (currently NO) º
º K. Synchronize "baud" rate (currently NO) º
º L. Send wakeup every 2 minutes (currently YES) º
º M. Create consistent .TR file º
º Q. Abandon changes º
º S. Save changes and leave installation program º
º º
º Selection: º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Refer to section 4 for the meaning of each option. The password is not so
critical here, since a user must be able to log into the mini-computer
before getting through to the node PC. The mini-computer line will not
provide any carrier information, so this must be ignored. "Baud" rates
must NOT be synchronized, since a NULL character transmitted at 2400 bps
would be received as a BREAK by the mini-computer at 9600 bps! To avoid
the node PC getting logged out, TRHOST must send a NULL character to
"wake up" the mini-computer every few minutes. This will be ignored by
TR.
Next the LAN manager selects option M from the main menu, and enters the
name of the configuration file he wishes to use for the node PC:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host Program .TR File Name Selection º
º º
º Edit existing string: º
º lan2 º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Finally the LAN manager exits TRHOSTIN by selecting option S to save the
changes. He can now make up a disk with all the installed TeleReplica
files on it to give to the remote users.
A4.3 Due to the way trfifo buffers input (or possibly some other peculiarity
of our mini-computer?) the delay between sending keys needs to be 165 ms
to avoid losing characters! Therefore, the line containing:
56 Time to wait between "typing" keys (ms)
must be changed to:
165 Time to wait between "typing" keys (ms)
Also, since we are using a mini-computer link, the line containing:
"DIRECT" Type of link (MODEM, DIRECT, or OTHER)
must be changed to:
"OTHER" Type of link (MODEM, DIRECT, or OTHER)
Finally, TR is capable of automating the mini-computer login process. If
this is desired, then something like the following lines must be added at
the end of the file:
"DISCONNECTED" "\D250\r" "\r" 5000
"Enter RESOURCE ? " "\D100G9000\r" "\r" 5000
"CONNECTED TO" "" "" 5000
"login: " "\D100doug\r" "\B\r" 500
"Password:" "\D100password\r" "\r" 10000
"Selection: " "\D100d\r" "" 40000
"/users/doug>" "\D100trfifo lan2\r" "" 40000
"and run TR" "\D1000" "" 40000
The exact strings will depend on the mini-computer. This example (apart
from the password) works for the author.
This completes the installation stage.
A4.4 When the remote user wishes to connect into the LAN, he will run TR:
TR LAN2
which will automatically log into the mini-computer and run trfifo to
connect to the node PC (in this case lan2).
TeleReplica will then synchronize "baud" rates, exchange passwords, and
give the remote user control of the node PC.
A4.5 When the remote user is finished, he will exit TR using option 3, which
will send a BREAK to the mini-computer. This will terminate the trfifo
program which the remote user was running. The trfifo program that the
node PC was running will detect that this has happened, and send a
TeleReplica reboot command to the node PC to ensure that the next user
cannot pick up anything the previous user left running. The node PC's
trfifo program will then prepare for the next remote user. The node PC
will complete rebooting, and run TRHOST from AUTOEXEC.BAT ready for the
next remote login.
[All this sounds complicated, but we use this system daily here at MUCG
for some staff who have mini-computer lines but are too far away for LAN
connections.]
A5. Home/Office via Modem
A5.1 Here a user wishes to dial in from home and take over the PC on his desk
at work. The office PC has a 2400 bps modem connected to COM2, and the
home PC has a 2400 bps modem connected to COM1. The office PC is equipped
with an EGA color display, and the home PC is equipped with a Hercules
monochrome display.
One problem is that since the office PC will be unattended, all it takes
is for the user to run a program which "hangs" the computer, and that
will be the end of the office PC until the user goes back to work and
presses the reset button! (Note that TeleReplica does support rebooting
the host PC, but this can only work if interrupts are not disabled and if
the relevant code has not been overwritten. As a rule, TeleReplica can
get out of any situation that
hardware reset button was needed TR would be helpless.)
Since the user is putting in overtime working at night without getting
paid for it, it seems reasonable that the office 'phone should at least
pay for the call. However, how can the office computer know when to call
the user at home? One possibility would be to set up a batch file to run
TRDIAL at a predetermined time. However, it would be better if the user
could choose any convenient time. TeleReplica can achieve this by
monitoring the RING signal from the modem, and responding appropriately.
The basic idea is that the user will dial the office number, and then
hang up as soon as the 'phone starts ringing. TeleReplica will detect the
'phone ringing, and respond by calling the user at home.
Since the user does not want to be bothered by nuisance calls from the
office computer, TeleReplica needs to be quite selective about the ring
patterns it will respond to. Too short a ring may mean a telephone
company routine line test. Too long a ring will mean a person trying to
ring the office. Even if the ring is the correct length, the user may
still wish to guarantee no interruptions between 11PM and 7AM!
The 'phone number of the office PC is 123 4567.
The 'phone number of the home PC is 765 4321.
A5.2 First the user must run TRHOSTIN, and make the changes necessary to
achieve something like the following display:
³ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
³plica Host 3.14 Installation Copyright (c) 1990 Douglas Thomson º
³ º
³Select serial port (currently COM2) º
³Change password (currently "fhkjeuyibn4593874sefeh8631wjds874dffd") º
³Change modem initialization string (currently: º
³"") º
³Change modem dialing format string (currently: º
³"\r%s\r") º
³Select maximum "baud" rate (currently 2400) º
³Use modem CARRIER DETECT signal (currently YES) º
³Flow control (currently NONE) º
³Generate INT 9 on each key (currently NO) º
³Respond to modem RING signal (currently YES)ÄÄÄÂÄ 1. too short 220 ms º
³Reboot on loss of carrier (currently YES) ÃÄ 2. too long 5000 ms º
³Synchronize "baud" rate (currently YES) ÃÄ 3. delay 10000 ms º
³Send wakeup every 2 minutes (currently NO) ÃÄ 4. reset 10000 ms º
³Create consistent .TR file ÀÄ 5. response Ä¿ º
³Abandon changes "\0x1Btrauto\r" º
³Save changes and leave installation program º
³ º
³ion: º
³ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Refer to section 4 for the meaning of each option. Since anyone could try
to get into the office PC the password is important - notice that it is
both long and quite random. The modem dialing format string permits ANY
modem command to be sent direct to the modem. It is essential that TRHOST
takes notice of the CD signal, since the host computer will be
automatically rebooted if the carrier is lost (see below). The host
computer is to monitor the 'phone ringing and respond accordingly (again,
see below). "Baud" rate synchronization is not important here.
Next the user selects option M from the main menu, and enters the name of
the configuration file he wishes to use for the office:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Host Program .TR File Name Selection º
º º
º Edit existing string: º
º office º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Finally the user exits TRHOSTIN by selecting option S to save the
changes. He can now make up a disk with all the installed TeleReplica
files on it to take home.
However, still on the office PC the user needs to create a batch file
called TRAUTO.BAT, containing something like:
trcheck 7:00:00 23:00:00
if errorlevel 1 goto done
trdial atd7654321
:done
which will check that the time is between 7AM and 11PM, and if so dial
the user's home number. Note that the "atd7654321" contains no spaces!
The user must also ensure that AUTOEXEC.BAT has the directory containing
all the TeleReplica files on the path, and that TRHOST is run whenever
the system boots. However, when the user is at the office he will not
want TRHOST loaded, so AUTOEXEC.BAT should contain something like:
prompt $p$g
path c:\tr
trkey
if errorlevel 1 goto done
trhost
:done
This will check to see if anything has been typed at the keyboard, and if
not will run TRHOST. If the user is at the office, then typing a key as
the system is booting will prevent TRHOST from loading.
A5.3 At home the user needs to edit the file named OFFICE.TR to install the
office PC's 'phone number. This means changing the line:
"" Connect command for modem
to:
"at d 123 4567\r" Connect command for modem
so that when the user runs TR the number will be dialed automatically.
Next, since the home modem is on COM1 the line:
"COM2" Communications port (COMn or base/interrupt)
must become:
"COM1" Communications port (COMn or base/interrupt)
Finally, TR should respond to the modem ringing by answering the 'phone.
This means adding an extra line at the end of the file containing:
"RING" "\D250ata\r" "" 40000
(Note the \D250 to wait a little bit for the modem to finish sending the
carriage return and line feed after RING before sending the answer
command. With some modems this may not be necessary; with others, a
different delay may work better. If the answer command is ignored, then
try a different delay.)
This completes the installation stage.
A5.4 Before leaving the office, the user must remember to reboot the PC (thus
loading TRHOST) and leave it turned on! However, it would be a good idea
to switch the monitor off.
When the user is ready to dial into the office PC from home, he will
enter the command:
TR OFFICE
This will cause the modem to dial the office PC. The user must then
listen to the modem and wait until he hears the 'phone ring once. As soon
as he hears this, he must press any key (say the space bar) to terminate
the call. TRHOST will start a timer going when the 'phone rings, and then
wait 10 seconds, keeping track of the total time the 'phone has spent
ringing. If, during the 10 seconds, the 'phone was ringing for more than
0.2 seconds but less than .9 seconds, then TRHOST will pretend to "type"
the keys:
The
ignored, and the trauto will run the TRAUTO.BAT script. The batch file
will check that the time of day is reasonable, and then call the user
back. When the user's 'phone rings, the modem will send the message:
RING
to the home PC, and TR will trigger on this to respond to the modem with:
ata
which will answer the 'phone. TeleReplica will then synchronize "baud"
rates, exchange passwords, and give the user control of the office PC.
A5.5 When the user is finished, he will exit TR using option 3, which will
cause the modem to hang up and terminate the 'phone call. The office PC
will then automatically reboot, ready for the user to call in again.
[This is probably the most complicated set up of all, but it is the one
the author has found most useful, and is in daily use by a number of
staff at MUCG.]
APPENDIX B - Sample File Transfer Session
B1 In this example, we will assume that a good link has been established as
described in scenario A2. The user has logged into the LAN from home, and
wishes to transfer all the C source files from the LAN directories:
F:\USERDATA\FRED\TEST
F:\USERDATA\FRED\UTILS
F:\USERDATA\FRED\PROBLEM
to the corresponding directories on his home PC:
C:\PROGRAMS\TEST
C:\PROGRAMS\UTILS
C:\PROGRAMS\PROBLEM
The current working directory on the LAN PC is F:\USERDATA\FRED. The
current working directory on the home PC is C:\TR.
First, the user needs to make C:\PROGRAMS the current working directory
on his home PC. To do this, he must hold down Ctrl, Alt, LeftShift and
RightShift all at the same time! This will bring up a screen similar to:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Copyright (c) 1990 Douglas Thomson º
º º
º Key Effect º
º === ====== º
º
º
º
º
º
º
º
º
º
º
º
º
º º
º
º Press key: º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
Then he should press
CD \PROGRAMS
to make C:\PROGRAMS the current working directory. Then he can enter the
command:
EXIT
to return to TR.
Next he needs to start the download. To do this he must again hold down
Ctrl, Alt, LeftShift and RightShift, and then press
will appear:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º Name(s) of file(s) to be downloaded (use DOS wildcards): º
º WARNING: Files with the same names on this PC will be overwritten! º
º º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
and he must enter the relative paths and wildcards:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º Name(s) of file(s) to be downloaded (use DOS wildcards): º
º WARNING: Files with the same names on this PC will be overwritten! º
º TEST\*.C TEST\*.H UTILS\*.C UTILS\*.H PROBLEM\*.C PROBLEM\*.H º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
If there were some problem (for example, if TRPUT.EXE were not on the
path of the LAN PC), then the following could be displayed:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º TeleReplica Error: º
º no ready marker from host º
º Type
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
However, normally the download will then commence, leaving the following
display:
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º File Transfer in Progress... º
º º
º File: test\xyz.c º
º º
º Error: º
º º
º Efficiency: 96.6% º
º º
º You may: º
º 1. Abort the file transfer º
º 2. Shell to DOS º
º º
º Selection: º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
The number of bytes remaining to be transferred is displayed in the top
right corner of the screen. The most recent error will be reported in the
appropriate line of the box, and the efficiency of the transfer (relative
to a perfect 10 bits per byte) may help to relieve the boredom while
waiting for the transfer to complete! The box also indicates which file
is currently being transferred.
At this stage, the user can either wait for the transfer to finish, or
else select option 2 from the menu and shell to DOS. In this case, he can
use his home PC for other jobs while the transfer takes place in the
background. TR will continue to display the number of bytes remaining in
the top right corner until the transfer is completed, at which time the
number in the top right corner will become the string "Completed" (or,
possibly, "Doubtful" if one or more files could not be created on the
home PC). However, the user must be careful not to do things like delete
the file that is being downloaded!
While shelled out to DOS in this way, the user may exit back into TR at
any time. If the file transfer is still in progress, then the file
transfer window will still be there; otherwise, the exit will leave TR
displaying the normal replica of the host PC's display.
APPENDIX C - Modem Cables
C1. Minimum Standard Modem Cable
Although a full 25-wire straight-through male-to-female RS232 cable is
recommended for TeleReplica (since there is less room for error in the
cable construction/selection), in fact the following signals are the only
ones ever required or used:
MALE (modem) FEMALE (PC)
============= ========
25D RS232 pin signal signal 25D 9D (as in AT)
============= ====== ====== === ==
2 TD <------- TD 2 3
3 RD -------> RD 3 2
4 RTS <------- RTS 4 7
5 CTS -------> CTS 5 8
7 GND <------> GND 7 5
8 CD -------> CD 8 1
20 DTR <------- DTR 20 4
22 RI -------> RI 22 9
The following sections describe the kind of null modem cables that can be
used with TeleReplica.
C2. Simplest Possible 3-wire Null Modem Cable
This is the most common kind of null modem cable, but TR and TRHOST must
be set to ignore carrier detect, since the cable does not provide this
information.
MALE FEMALE
============= ========
25D RS232 pin signal signal 25D 9D (as in AT)
============= ====== ====== === ==
7 GND <------> GND 7 5
3 RD <------- TD 2 3
2 TD -------> RD 3 2
C3. Full TeleReplica Null Modem Cable
If you can build or get hold of one of these, then TeleReplica can use
carrier detect correctly. Note that CTS is not provided, and that
TeleReplica must therefore be installed not to use it (there would be no
point is using flow control with a direct cable in any case)!
MALE FEMALE
============= ========
25D RS232 pin signal signal 25D 9D (as in AT)
============= ====== ====== === ==
7 GND <------> GND 7 5
3 RD <------- TD 2 3
2 TD -------> RD 3 2
20 DTR -------> CD 8 1
8 CD <------- DTR 20 4
C4. Complete Null Modem Cable
If you really want a complete null modem cable, which should work with
ANY communications program, then I would suggest:
MALE FEMALE
============= ========
25D RS232 pin signal signal 25D 9D (as in AT)
============= ====== ====== === ==
7 GND <------> GND 7 5
3 RD <------- TD 2 3
2 TD -------> RD 3 2
5 CTS <------- RTS 4 7
4 RTS -------> CTS 5 8
20 DTR ----+--> CD 8 1
|
+--> DSR 6 6
8 CD <--+---- DTR 20 4
|
6 DSR <--+
APPENDIX D - DESQview Compatibility
D1. TR is "DESQview-Aware" and runs nicely in a small DESQview window. TRHOST
needs to put keys into the BIOS keyboard buffer, and this means that what
is typed at the remote end cannot be distinguished by DESQview from what
is typed at the real keyboard at the host end. The net effect is that
there is no point in trying to run TRHOST in a DESQview window, and so
TRHOST makes no attempt to be "DESQview-Aware". Also, DESQview is
activated by "tapping" the ALT key, but TRHOST has no way to make this
appear to happen, hence DESQview cannot be activated remotely. In
addition, although TRHOST can be loaded high using QEMM, the reboot
function is not compatible with being loaded high, so I recommend NOT
trying to load TRHOST high. TRHOST and DESQview really don't mix!
D2. For anyone wishing to set up DESQview for TR, these are the settings that
I am currently using successfully:
É1ÍÍChangeÍaÍProgramÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º Change a Program º
º º
º Program Name............: TR º
º º
º Keys to Use on Open Menu: TR Memory Size (in K): 64 º
ºÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄĺ
º Program...: C:\TR\TR º
º º
º Parameters: REMOTE º
º º
º Directory.: \TR º
ºÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄĺ
º Options: º
º Writes text directly to screen.......: [N] º
º Displays graphics information........: [N] º
º Virtualize text/graphics (Y,N,T).....: [N] º
º Uses serial ports (Y,N,1,2)..........: [1] º
º Requires floppy diskette.............: [N] º
º º
º Press F1 for advanced options Press <ÄÙ when you are DONE º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
and advanced options:
É1ÍÍChangeÍaÍProgramÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
º Change a Program Advanced Options º
º º
º System Memory (in K): 0 Maximum Program Memory Size (in K)..: 64 º
º º
º Script Buffer Size: 100 Maximum Expanded Memory Size (in K): 0 º
º º
º Text Pages: 1 Graphics Pages: 0 Initial Mode: Interrupts: 00 to 2F º
ºÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄĺ
º Window Position: º
º Maximum Height: 25 Starting Height: 25 Starting Row...: 1 º
º Maximum Width.: 80 Starting Width.: 80 Starting Column: 1 º
ºÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄĺ
º Shared Program º
º Pathname..: º
º Data......: º
ºÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄĺ
º Close on exit (Y,N,blank)..: [Y] Uses its own colors...........: [Y] º
º Allow Close Window command.: [N] Runs in background (Y,N,blank): [Y] º
º Uses math coprocessor......: [N] Keyboard conflict (0-4).......: [0] º
º Share CPU when foreground..: [Y] Share EGA when foreground/....: [Y] º
º Can be swapped out (Y,N, ).: [N] Protection level (0-3)........: [0] º
º º
º Press F1 for standard options Press <ÄÙ when you are DONE º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
D3. When running under DESQview, the "shell to DOS" option during a file
transfer is disabled, since DESQview does not permit interrupt handlers
to call DOS and BIOS functions (necessary for reading and writing files).
However, this is not a serious limitation under DESQview, since DESQview
will allow you to run multiple simultaneous programs.
D4. The normal "shell to DOS" option may be used under DESQview, but in this
case more than 64K of memory will need to be allocated - with 4dos, it
has been reported that at least 150K is required!
APPENDIX E - Acknowledgements
I would like to thank all the users of TeleReplica who have helped me to
improve the package by suggesting new features and reporting
difficulties. The following individuals in particular have had a
significant impact on the current version:
Lindsay Smith
Timo Salmi
Very nice! Thank you for this wonderful archive. I wonder why I found it only now. Long live the BBS file archives!
This is so awesome! 😀 I’d be cool if you could download an entire archive of this at once, though.
But one thing that puzzles me is the “mtswslnkmcjklsdlsbdmMICROSOFT” string. There is an article about it here. It is definitely worth a read: http://www.os2museum.com/wp/mtswslnk/