home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Columbia Kermit
/
kermit.zip
/
archives
/
pckermit.tar.gz
/
pckermit.tar
/
pckermitdoc.txt
< prev
next >
Wrap
Text File
|
1988-08-24
|
38KB
|
932 lines
10. PC-DOS and MS-DOS KERMIT-86
Program: Daphne Tzoar, Columbia University, with contributions from Jeff
Damens (Columbia), Dave King (CMU), Herm Fischer (Litton Data
Systems), and others.
Documentation:
Frank da Cruz, Columbia University; Herm Fischer, Litton Data Sys-
tems (Van Nuys CA)
Version: 2.25
Date: February 1984
KERMIT-86 is a program that implements the KERMIT file transfer protocol for
the IBM PC and several other machines using the same processor family (Intel
8088 or 8086) and operating system family under PC-DOS or MS-DOS (henceforth
referred to collectively as MS-DOS), versions 1.1, 2.0, and 2.1. This section
will describe the things you should know about the MS-DOS file system in order
to make effective use of KERMIT, and then it will describe the KERMIT-86
program.
MS-DOS KERMIT runs on a variety of systems, including the IBM PC and XT, the
the Heath/Zenith 100, HP-150, the Seequa Chameleon, the Victor 9000, the Tandy
2000, the Compaq Portable, the Columbia MPC, and others. This document con-
centrates on the IBM PC/XT implementation; the others will be (possibly
complete) subsets of that (see Section 10.5 for details about support for other
MS DOS systems).
10.1. The MS-DOS File System
The features of the MS-DOS file system of greatest interest to KERMIT users are
the form of the file specifications, and the distinction between pre-MS-DOS 2.0
file names and newer file names which allow directory paths.
MS-DOS FILE SPECIFICATIONS
MS-DOS file specifications are of the form
DEVICE:\PATHNAME\NAME.TYPE
where the DEVICE is a single character identifier (e.g., A for the first floppy
disk, C for the first fixed disk, D for a RAM disk emulator), PATHNAME is up to
63 characters of identifier(s) (up to 8 characters each) surrounded by reverse
slashes (or ".." for parent or "." for current directory), NAME is an iden-
tifier of up to 8 characters, and TYPE is an identifier of up to 3 characters
in length. Device and pathname may be omitted. Pathname is normally omitted,
and cannot be specified for MS-DOS 1.x or with those commands which allow
MS-DOS 1.x use (e.g. pathnames can only be accepted by commands which are
specific to MS-DOS 2.x). Device and directory pathnames, when omitted, default
to the user's current (or "defaulted") disk and directory path (path=".").
Thus NAME.TYPE is normally sufficient to specify a file, and only this infor-
mation is sent along by KERMIT-86 with an outgoing file.
The device, path, name, and type fields may contain uppercase letters, digits,
and the special characters "-" (dash), "_" (underscore), and "$" (dollar sign).
(For use only among MS-DOS processors, additional filename special characters
allowed are "#&!%(){}'`". DOS 1.x allows others as well.). There are no im-
bedded or trailing spaces. Other characters may be not be included within the
MS-DOS environment (e.g. quoted characters are not permissible). The fields of
the file specification are set off from one another by the punctuation in-
dicated above.
The device field specifies a physical or "logical" device upon which the file
is resident. The directory pathname identifies an area on the device, for in-
stance the area belonging to the logical ownership of the file. KERMIT-86 does
not transmit the device or pathname directory fields to the target system, and
does not attempt to honor device or directory fields that may appear in incom-
ing file names.
The name field is the primary identifier for the file. The type, also called
the "extension", is an indicator which, by convention, tells what kind of file
we have. For instance FOO.BAS is the source of a BASIC program named FOO;
FOO.OBJ might be the relocatable object module produced by compiling FOO.BAS;
FOO.EXE could an executable program produced by linking FOO.OBJ, and so forth.
The MS-DOS allows a group of files to be specified in a single file specifica-
tion by including the special "wildcard" characters, "*" and "?". A "*"
matches any string of characters from the current position to the end of the
field, including no characters at all; a "?" matches any single character.
Here are some examples:
*.BAS All files of type BAS (all BASIC source files) in the current direc-
tory.
FOO.* Files of all types with name FOO.
F*.* All files whose names start with F.
F?X*.* All files whose names start with F and contain X in the third position,
followed by zero or more characters.
?.* All files whose names are exactly one character long.
Wildcard notation is used on many computer systems in similar ways, and it is
the mechanism most commonly used to instruct KERMIT to send a group of files.
KERMIT-86 uses the ? character for help while commands are being typed, so the
single-character wildcard in KERMIT commands is = rather than ?, for example
Kermit-86>send =.*
The KERMIT-86 user must bear in mind that other (non-MS-DOS) systems use dif-
ferent wildcard characters; for instance KERMIT-20 uses % instead of the ? as
the single character wildcard. When using KERMIT-86 to request a wildcard file
group from a KERMIT-20 server, the Kermit-86 "=" must be replaced by DEC-20 "%"
characters.
TEXT FILES AND BINARY FILES
The MS-DOS systems store files as bulk collections of 8 bit bytes, with no
peculiar differences between text, program code, and binary files. Since a
non-MS-DOS receiving system might need to know file type distinctions, the user
might need to use various SET functions on the remote system to inform it that
the incoming file is of some particular (non-default) type. In transmitting
files between KERMIT-86'es, regardless of file contents, the receiving MS-DOS
system is equally capable of processing text, code, and data (and is, in fact,
not knowledgable of the usage of the bytes in the file).
ASCII files are presumed to have recognizable characteristics (carriage returns
and linefeeds delimiting lines, form feeds delimiting pages, and control-Z's
delimiting the end of file), though all internal bit codes are transmitted.
Receiving non-MS-DOS systems may well get confused when presented with nonstan-
dard ASCII files. Files produced by EASYWRITER or Word Star, for example, may
need preprocessing prior to transmission by commonly available "exporter"
programs, to convert them to conventional ASCII formats. Spreadsheet data
files, and dBASE II files need special formatting to be meaningful to non-
MS-DOS recipients (though they can be transmitted between MS-DOSes with
KERMIT-86's). Furthermore, those word processors storing formatting data at
the end of the file, after the control-Z and before physical end (such as BLUE
or Easy Writer), will need to be told to strip the formatting data, lest they
confuse non-MS-DOS recipients.
10.2. Program Operation
KERMIT-86's prompt is "Kermit-86>". KERMIT-86 can run interactively to issue
several commands, like this:
A>
A>kermit
MS DOS Kermit V2.25
Kermit-86>send foo.*
informational messages about the files being sent
Kermit-86>status
various status informational data are displayed
Kermit-86>receive
informational messages about the files being recieved
Kermit-86>exit
A>
During interactive operation, you may use the help ("?") and recognition (ESC)
features freely while typing commands. Command keywords may be abbreviated to
their shortest prefix that sets them apart from any other keyword valid in that
field.
10.3. MS DOS KERMIT Commands
MS DOS KERMIT implements a large subset of the local mode commands of "ideal"
KERMIT. Not all of the following commands are available on all MS DOS systems,
and some of the commands may work somewhat differently between DOS versions.
THE SEND COMMAND
Syntax: SEND filespec
The SEND command causes a file or file group to be sent from the MS-DOS to the
other system. The filespec may contain a device designator, like A:, and the
wildcard characters "*" and/or "=". The current release of Kermit-86 does not
allow pathnames in this command.
If the filespec contains wildcard characters then all matching files will be
sent, in directory search order (according to how your MS-DOS lists its direc-
tory contents). If a file can't be opened for read access, standard MS-DOS
recovery procedures will be available (these may necessitate restarting
Kermit).
SEND Command General Operation
Files will be sent with their MS-DOS filename and filetype (for instance
FOO.TXT, no device or pathname). If you expect to be sending files whose names
contain characters that would be illegal in filenames on the target system, and
you know that Kermit on the target system does not have the ability to convert
incoming filenames, you can copy and/or rename the file using MS-DOS commands
prior to loading Kermit.
Each file will be sent as a sequence of eight bit bytes.
Once you give KERMIT-86 the SEND command, the name of each file will be dis-
played on your screen as the transfer begins; a packet count and retry summary
will be displayed, and informational messages displayed as appropriate. If the
file is successfully transferred, you will see "COMPLETED", otherwise there
will be an error message. When the specified operation is done, the program
will sound a beep.
If you notice a file being sent which you do not really want to send, you may
cancel the operation immediately by typing either Control-X or Control-Z. If
your are sending a file group, Control-X will cause the current file to be
skipped, and KERMIT-86 will go on to the next file, whereas Control-Z will can-
cel sending the entire group and return you to KERMIT-86 command level. A
Control-C cancels sending immediately and returns you to the Kermit-86 prompt.
THE RECEIVE COMMAND
Syntax: RECEIVE [filespec]
The RECEIVE command tells KERMIT-86 to receive a file or file group from the
other system. KERMIT simply waits for the file to arrive; this command is not
to be used when talking to a KERMIT server (see GET).
If the optional filespec is provided, store the incoming file under that name.
The filespec may include a device designator, or may consist of only a device
designator. The incoming file is stored on the default or specified device
(current directory in DOS 2.0). If no name was specified, the name from the
incoming file header packet is used; if that name is not a legal MS-DOS file
name, KERMIT-86 will delete illegal or excessive characters from the name.
If the optional filespec was provided, but more than one file arrives, the
first file will be stored under the given filespec, and the remainder will be
stored under their own names.
If the incoming file name already exists, and FILE-WARNING is set, KERMIT-86
will change the incoming name (and inform you how it renamed it) so as not to
obliterate the pre-existing file.
If an incoming file does not arrive in its entirety, KERMIT-86 will normally
discard it; it will not appear in your directory. You may change this behavior
by using the command SET INCOMPLETE KEEP, which will cause as much of the file
as arrived to be saved in your directory.
If a file begins to arrive that you don't really want, you can attempt to can-
cel it by typing Control-X; this sends a cancellation request to the remote
Kermit. If the remote Kermit understands this request (this is an optional
feature), it will comply; otherwise it will continue to send. If a file group
is being sent, you can request the entire group be cancelled by typing
Control-Z. If you type Control-C, you will be returned immediately to the
Kermit-86> command level.
THE GET COMMAND
Syntax: GET remote-filespec
The GET remote-filespec command requests a remote KERMIT server to send the
file or file group specified by remote-filespec. This command can be used only
when KERMIT-86 is local, with a KERMIT server on the other end. This means
that you must have CONNECTed to the other system, logged in, run KERMIT there,
issued the SERVER command, and escaped back (e.g. ^]C) to the local KERMIT-86.
The remote filespec is any string that can be a legal file specification for
the remote system; it is not parsed or validated locally. (A remote PC server
will accept device names, but not path names in the filespec.) As files ar-
rive, their names will be displayed on your screen, along with packet traffic
statistics and error messages. You may type ^X to request that the current in-
coming file be cancelled, ^Z to request that the entire incoming batch be can-
celled, and ^C to return immediately to the Kermit-86> prompt.
If the remote KERMIT is not capable of server functions, then you will probably
get an error message back from it like "Illegal packet type". In this case,
you must connect to the other Kermit, give a SEND command, escape back, and
give a RECEIVE command.
THE BYE COMMAND
When running a local Kermit which is talking to a remote KERMIT server over a
communications line, use the BYE command to shut down the server and log out
its job, and exit from Kermit-86 to DOS.
THE FINISH COMMAND
Like BYE, FINISH shuts down the remote server. However, FINISH does not log
out the server's job. You are left at Kermit-86 prompt level so that you can
connect back to the job on the remote system.
THE LOGOUT COMMAND
The LOGOUT command is identical to the BYE command, except you will remain at
Kermit-86 prompt level, rather than exit to DOS, so that you can establish
another connection.
THE CONNECT COMMAND
Syntax: CONNECT
Establish an interactive terminal connection to the system connected to the
currently selected communications port (COM1 or COM2) using full duplex echoing
and no parity unless otherwise specified in previous SET commands. Get back to
KERMIT-86 by typing the escape character followed by the letter C. The escape
character is Control-] by default. When you type the escape character, several
single-character commands are possible:
? Help - prints the commands allowed (as below).
C Close the connection and return to KERMIT-86.
S Status of the connection.
B Break signal is sent to the port (on the PC/XT you may also type
CTRL-BREAK to send a BREAK).
^] (or whatever you have set the escape character to be)
Typing the escape character twice sends one copy of it to the connected
host.
You can use the SET ESCAPE command to define a different escape character, and
on some systems (including the PC and XT) you can SET BAUD to change the baud
rate, and SET PORT to switch between COM1 and COM2
In the connect mode, you can communicate with your autodialer, control the com-
munications line, hang it up, and the like. (E.g., typing +++ to a Hayes-like
modem will allow you to follow that by dialing or hang-up commands, when in the
connection state).
THE REMOTE COMMAND
The REMOTE keyword is a prefix for a number of commands. It indicates that the
command is to be performed by the remote Kermit, which must be running as a
server. Note that not all Kermit servers are capable of executing all these
commands. In case you send a command the server cannot execute, it will send
back a message to the effect that the command is unknown to it. If the remote
can execute the command, it will send the results to your screen. Here are the
REMOTE commands which KERMIT-86 may issue:
CWD [directory] Change Working Directory on the remote host. Change the
default source and destination area for file transfer.
DELETE filespec Delete the specified file or files on the remote host. In
response, the remote host should display a list of the files
that were or were not successfully deleted.
DIRECTORY [filespec]
The remote host will provide a directory listing of the
specified files. If no files are specified, then all files in
the default area will be listed.
DISK [directory]
Provide a brief summary of disk usage in the specified area on
the remote host. If none specified, the default or current
area will be summarized.
HELP The remote host tells what server functions it is capable of.
HOST [command] Send the command to the remote host's command processor for ex-
ecution.
TYPE filespec Display the contents of the specified remote file or files on
the screen.
THE SET COMMAND
Syntax: SET parameter [value]
Establish or modify various parameters for file transfer or terminal connec-
tion. You can examine their values with the STATUS command. The following
parameters may be SET:
BACKARROW Backarrow (backspace) key sends BACKSPACE or DELETE.
BAUD Communications port line speed
BELL The bell (beep) is normally sounded at the end of a trans-
action. SET BELL OFF may be used to silence the bell.
DEBUG Mode
END-OF-LINE Character to replace CR at end of packets
ESCAPE Character for Kermit-86 attention during terminal connection
FILE-WARNING Warn if an incoming filename would conflict with an existing
file name, and attempt to construct a new unique name for it.
HEATH-19 Interpret Heath/Zenith-19 screen control codes.
IBM Set up for communication with IBM mainframes: local echo (half
duplex) during terminal emulation, line turnaround handshake
during file transfer, and appropriate parity at all times.
INCOMPLETE What to do with an incomplete file, KEEP or DISCARD.
LOCAL-ECHO For terminal connection, OFF (remote echo, or full duplex) or
ON (local echo, or half duplex)
PARITY Character parity to use, NONE (the default), ODD, EVEN, MARK,
or SPACE
PORT RS232 port to use for terminal connection or file transfer,
COM1 (the default) or COM2
SET BACKARROW
Syntax: SET BACKARROW state
The IBM PC keyboard does not have a key marked DELETE (RUBOUT) or BACKSPACE.
DELETE and BACKSPACE are two different ASCII characters (ASCII 127 and ASCI 8
respectively), and one or the other of these characters is normally used by
host systems for deleting the characters just typed. Some systems use BACK-
SPACE, some use DELETE. This command allows you to specify which character the
backarrow key should transmit during terminal connection.
BACKSPACE Backarrow (backspace) key transmits the backspace (BS) charac-
ter, Control-H. CTRL-Backarrow sends DELETE.
DELETE Backarrow (backspace) key transmits the delete (DEL, RUBOUT)
character. CTRL-Backarrow sends BACKSPACE.
In all cases, CTRL-H sends BACKSPACE.
SET BAUD
Syntax: SET BAUD rate
Set terminal communications port speed to 300, 1200, 1800, 2400, 4800, 9600 or
other common baud rates. The site default baud rate can be determined by the
STATUS command immediately upon loading Kermit-86, and is displayed upon is-
suing of the CONNECT command.
SET BELL
Syntax: SET BELL state
ON Bell (beeper) sounds, at completion of transmissions and other
times.
OFF Bell (beeper) remains silent.
SET DEBUG
Syntax: SET DEBUG state
ON Record the packet traffic on your terminal.
OFF Don't display debugging information (this is the default). If
debugging was in effect, turn it off.
SET END-OF-LINE
Syntax: SET END-OF-LINE decimal number between 0 and 31
Change the character used at the end of outgoing packets to the character whose
decimal ASCII value is given. The default is 13 (carriage return).
SET ESCAPE
Syntax: SET ESCAPE character Specify the control character you want to use to
"escape" from remote connections back to KERMIT-86. The default is Control-].
SET FILE-WARNING
Syntax: SET FILE-WARNING option
Specify what to do when an incoming file has the same name as an existing file
in the default directory of the default device. If ON, Kermit will warn you
when an incoming file has the same name as an existing file, and automatically
rename the incoming file (as indicated in the warning) so as not to destroy
(overwrite) the pre-existing one. If OFF, the incoming file replaces the
pre-existing file.
SET HEATH-19
Syntax: SET HEATH-19 option
ON Specifies that, in the connect state, incoming characters are to be ex-
amined for Heath/Zenith-19 terminal screen control commands (escape
sequences), and if encountered, the commands are to be emulated on the
PC screen. The Heath-19 codes are a superset of the popular DEC VT52
codes, so if your system does not support the Heath-19, you may tell
your terminal type is VT52 (or one of the many VT52 compatibles).
Heath-19 emulation is available on the IBM PC and XT.
OFF All incoming characters will be sent to the screen "bare", through DOS.
If you have loaded a device driver into DOS for the CON: device, such
as ANSI.SYS, then that driver will be able to interpret the codes it-
self. Most non-IBM systems have their own screen control code inter-
preter built into DOS or firmware.
On the IBM systems, function keys and numeric keypad cursor control keys do not
send characters when in the Heath-19 mode, unless the user has used a key
redefinition package like ProKey.
SET IBM
Syntax: SET IBM option
Specify setup for communication with an IBM mainframe. ON sets appropriate
parity (per options used to assemble Kermit at your site, MARK as distributed),
local echo for CONNECT, and half-duplex line handshaking (XON line turnaround).
OFF reestablishes full duplex, nonparity operation.
SET LOCAL-ECHO
Syntax: SET LOCAL-ECHO option
Specify mode for character echoing when in the CONNECT state. ON specifies
that characters are to be echoed within Kermit (because neither the remote com-
puter, nor the communications circuitry has been requested to echo). Generally
IBM mainframes accessed directly (not via Telenet) will need this option (or
the IBM option, q.v.) ON; generally most DEC sites and inter-PC communications
will need it OFF. It is OFF by default, i.e. communication is assumed to be
full duplex (remote echo).
SET PARITY
Syntax: SET PARITY keyword
The choices for SET PARITY are NONE (the default), ODD, EVEN, MARK, and SPACE.
NONE means no parity processing is done, and the 8th bit of each character can
be used for data when transmitting binary files.
You will need to SET PARITY to ODD, EVEN, MARK, or possibly SPACE when com-
municating with a system, or over a network, that requires or imposes character
parity on the communication line. For instance, GTE TELENET requires MARK
parity. If you neglect to SET PARITY when the communications equipment re-
quires it, the symptom may be that terminal emulation works partially, and file
transfer does not work at all.
If you have set parity to ODD, EVEN, MARK, or SPACE, then KERMIT-86 will re-
quest that binary files will be transferred using 8th-bit-prefixing. If the
other side knows how to do 8th-bit-prefixing (this is an optional feature of
the KERMIT protocol, and not all implementations of KERMIT have it), then bi-
nary files can be transmitted successfully. If NONE is specified, 8th-bit-
prefixing will not be requested.
SET PORT
Syntax: SET PORT number
Specify the port number to use for file transfer or CONNECT, COM1 or COM2.
This command lets you use a different asynchronous adapter, or to switch be-
tween two simultaneous remote sessions.
THE STATUS COMMAND
Report the status of parameters which can be modified by the SET commands.
10.4. Installation
Kermit-86 is written in 8086 Macro Assembler (ASM86), and assembled locally on
the micro. Versions for the IBM PC (PC DOS) and the Heath/Zenith Z100 (MS DOS)
are prepared from common source using conditional assembly switches similar to
those in KERMIT-80. The IBM flag has site-dependent meaning. As shipped from
Columbia, it means local echo during CONNECT, mark parity, and half duplex line
handshaking using CTRL-Q as the turnaround character. If you need to install
Kermit on your PC, and you do not have a Kermit floppy but you do have access
to a mainframe computer with a copy of the IBM PC Kermit distribution, you
should read this section.
Since the PC assembler is not provided with the minimum system, IBM PC users
cannot be expected to have it. Assembler source plus the runnable version
16
(.EXE) of Kermit are distributed , along with some special "bootstrap" files,
described below.
The KERMIT.EXE file is converted by an assembler program on the PC, KFIX, which
makes all bytes in the file printable by breaking each one up into two 4-bit
"nibbles" and adding a constant. The result is a printable file called
KERMIT.FIX. It is assumed that a copy of KERMIT.FIX is available to you on a
mainframe computer. To download the file to the PC, two cooperating programs
are run: a Fortran program, KSEND, on the mainframe and a Basic program, KGET,
on the PC. These programs are very short; they are shown in their entirety
below. KSEND reads a line at a time from KERMIT.FIX, types the line, and waits
for a signal from KGET that it can send more data. KGET reads each line and
converts the text back to the format of an executable (.EXE) file. Here's the
procedure:
1. You should have a version of KGET on the PC and KSEND on the
mainframe; if you don't have them, copy them (i.e. type them in,
_______________
16
The PC assembler's object (.OBJ) files are not printable, like CP/M hex
files, so the Kermit-80 bootstrapping technique would not work here.
17
using an editor ) from the listings below.
2. Log in on the mainframe. This could be tricky if you have no ter-
minal emulation facility on the PC. If you have the IBM
asynchronous communication package, you can do this at low speeds
(baud rates). If your PC has no terminal emulation facility, you'll
have to use a real terminal to log in, and then switch the cable to
the PC.
3. Compile KSEND.FOR on your mainframe, if it needs compiling. Define
logical unit numbers 5 and 6 to be the controlling terminal, and
logical unit number 7 to be KERMIT.FIX. On the DEC-20, for example:
@define 5: tty:
@define 6: tty:
@define 7: kermit.fix
On a DECsystem-10, do something like:
.assign tty: 5:
.assign tty: 6:
.assign dsk: 7:
.rename for007.dat=kermit.fix
On an IBM system under VM/CMS,
.filedef 5 term ( lrecl 64 recfm f
.filedef 6 term ( lrecl 64 recfm f
.filedef 7 disk kermit fix ( lrecl 62 recfm f perm
Start KSEND on the mainframe. It will print a message, and then sit
and wait for the PC to send back an OK; don't change any connectors
until you see the message.
4. Escape back to the PC, or connect the PC to the mainframe. The PC's
communication port should be connected with a cable to the modem
that's connected to the mainframe (dialup, dedicated, switched,
whatever hookup you normally have available for logging in on the
mainframe from a terminal). If you were using a different terminal
to log in to the mainframe, make sure the PC's communication port is
set at the same speed.
5. Enter BASIC and run KGET on the PC. If KGET prints messages about
i/o errors, run it again. If it still gets errors, reboot the PC
and try again. Once KGET is running, the transmission will begin.
KGET will print each 62-character line of nibbles as it arrives from
the mainframe. Each line should be the same length -- if you see a
ragged edge, you can assume there has been a transmission error, and
you should start the process again.
_______________
17
You'll also have to compile and load the KSEND program on the mainframe.
6. When transmission is complete, you'll see the BASIC "Ready" prompt
again. Leave BASIC by typing SYSTEM. You should now have
KERMIT.EXE on your PC. Try to run it. If you see the "Kermit-86>"
prompt, try to CONNECT to the host mainframe and transfer some
files. If Kermit doesn't run correctly, there may have been trans-
mission errors, in which case you should start the process again
from step 2 above.
KSEND.FOR - Mainframe Side of Bootstrap
This is the mainframe side, KSEND, in transportable Fortran (it should run on
both DEC and IBM mainframes):
C This Fortran program should be run on the mainframe in conjunction
C with a Basic program on the IBM PC to transfer Kermit.Fix to the PC
INTEGER A(62)
WRITE(6,50)
50 FORMAT(' Ready to transfer data......')
C Get terminal handshake
100 READ (5,10,END=35)X
10 FORMAT(A1)
C Get line from file
35 READ (7,20,END=90)A
20 FORMAT(62A1)
C Write to tty
WRITE (6,25)A
25 FORMAT(' ',62A1,';')
GOTO 100
90 CONTINUE
C Get final handshake
WRITE (6,30)
30 FORMAT(' ',63('@'))
STOP
END
The final @'s tell KGET that the transmission is done. This works because the
technique for forming KERMIT.FIX ensures that the file will contain no @'s.
KGET.BAS -- PC Side of Bootstrap
This is the PC side, KGET, in PC Basic. Note that the communication port is
opened at 4800 baud (you could substitute any other speed).
5 'Run this program on the PC in conjunction with a Fortran program on t
6 ' mainframe to get Kermit to the PC
7 ' Daphne Tzoar , December 1983
8 ' Columbia University Center for Computing Activities
9 '
10 OPEN "com1:4800,n,8,1" AS #1 ' Clear the port status.
20 CLOSE #1
30 OPEN "com1:4800,n,8,1,cs,ds,cd" AS #1
40 OPEN "KERMIT.EXE" FOR OUTPUT AS #2
50 OK$ = "ok"
60 PRINT#1,OK$ ' Tell host we're ready for data
70 X$=INPUT$(63,#1) ' Data plus semi-colon
80 VALUE$ = LEFT$(X$,1) 'First char of input
90 VALUE = ASC(VALUE$)
100 IF VALUE = 64 OR VALUE = 192 GOTO 430 ' @ means we're done
110 IF VALUE >= 176 AND VALUE <= 191 THEN GOTO 140 ' Kill all illegal c
120 IF VALUE >= 48 AND VALUE <= 63 THEN GOTO 140
130 X$ = MID$(X$,2) : GOTO 80
140 IF VALUE <> 174 GOTO 210 ' Not a dot (for read) - don't worry
150 TWO$ = MID$(X$,2,1) ' Look at char after the dot.
160 TWO = ASC(TWO$)
170 IF TWO >= 176 AND TWO <= 191 THEN GOTO 210 ' It's ok.
180 IF TWO >= 48 AND TWO <= 63 THEN GOTO 210
190 X$ = MID$(X$,3) ' Kill the char
200 GOTO 80
210 SIZ = LEN(X$) ' How much input was actual data
220 READIN = 64 - SIZ
225 IF READIN = 0 GOTO 260
230 XTWO$=INPUT$(READIN,#1) ' Get rest of data
240 X$ = X$ + XTWO$ : X$ = LEFT$(X$,62)
250 PRINT X$ ' Optional - use this line to follow the transmissio
260 GOSUB 290
270 PRINT#2,X$; ' Put data to the file.
280 GOTO 60
290 ' GET TWO CHARS, SUBTRACT SPACE (20 HEX) FROM EACH, AND COMBINE
300 ' TO ONE DIGIT.
310 FOR A = 1 TO 31
320 Y$ = MID$(X$,A,1)
330 Z$ = MID$(X$,A+1,1)
340 YNUM = ASC(Y$) : ZNUM = ASC(Z$)
350 IF YNUM > 127 THEN YNUM = YNUM - 128 ' Turn off hi bit if on
360 IF ZNUM > 127 THEN ZNUM = ZNUM - 128
370 YNUM = YNUM -48 : ZNUM = ZNUM -48 ' Subtract the space
380 XNUM = (16 * YNUM) +ZNUM
390 NEWCHR$ = CHR$(XNUM)
400 X$ = MID$(X$,1,A-1) + NEWCHR$ + MID$(X$,A+2)
410 NEXT A
420 RETURN
430 PRINT " [All done.]"
440 CLOSE #1,#2 ' Clean up.
450 END
If you already have a working Kermit on your PC and you want to get a new one,
you should use Kermit itself to transfer the KERMIT.FIX file. Once you have
the new KERMIT.FIX on your PC disk:
1. Rename KERMIT.EXE to something else, so you'll still have it in case
something goes wrong.
2. Get or copy the program KEXE from the mainframe. Alternatively, you
may modify KGET as follows:
a. Remove lines 10 and 20.
b. Change line 30 to
30 OPEN "KERMIT.FIX" FOR INPUT AS #1
c. Remove line 60, since we're not handshaking with a remote host
any more.
d. In line 70, change "63" to "62".
e. Remove line 250, since there's no need to monitor a transmis-
sion line.
f. Change line 280 from "GOTO 60" to "GOTO 70".
Save the modified KGET under a new name, say KEXE.BAS, and run it.
It will end with some error like "Input past end in 70", which just
means it came to the end of file (of course, you could avoid this
error by trapping it, but no harm is done in any case).
3. You should now have a new, working version of KERMIT.EXE on your PC
disk.
10.5. Adding Support for New Systems
MS DOS Kermit supports many different systems. Like CP/M-80 KERMIT, this sup-
port was added to the program piecemeal, at many sites, using conditional as-
sembly. However, before allowing the program to grow into a complicated
monolith like CP/M-80 KERMIT, we have broken the program up into separate
modules, with system dependencies isolated into separate modules, consisting of
compact collections of low-level primitives for console and port i/o.
The last monolithic (single source file) release of MS DOS Kermit was 1.20. To
this and earlier versions was added support for systems like the Seequa
Chameleon, the HP-150, the Victor 9000, the Heath/Zenith 100, and others. As
time permits, support for these systems will be integrated with the new modular
version. Meanwhile, implementations based on these old versions will have at
least the following incompatibilies from the version described here:
- RECEIVE filespec is used instead of GET filespec. There is no GET
command in older versions, and no way to specify a new name for an
incoming file.
- No REMOTE command.
- No 8th-bit prefixing.
To install support for a new system, you would copy the system-dependent
modules for terminal emulation and port and console i/o, modify them to suit
the requirements of your machine, and rebuild the program. In many cases, a
"generic" MS DOS Kermit will run as-is on new systems. The generic version ac-
complishes all its port and console i/o through DOS calls, and does no terminal
emulation -- many systems do not need terminal emulation because they have ter-
minal firmware built in.
Details to be filled in...
Index
8086/8088 90
Backarrow 87
Baud Rate 87
Beeper 88
Bell 88
Binary Files 89
Cancelling a File Transfer 83, 84
Control-C 83, 84
Control-X 83, 84
Control-Z 83, 84
Debugging 88
DECsystem-10 91
Downloading 90
Eighth-Bit Prefix 89
End of line character 88
Escape Character for CONNECT 88
File Renaming 88
File Warning 88
Function Keys 89
Heath-19 Terminal Emulation 88
Help 82
IBM Compatibility 89
IBM PC 80, 90
Incomplete File Disposition 84
Initial Filespec 83
KEXE 94
KFIX 90
KGET 90
KSEND 90
Local Echoing 89
MS-DOS 80
Normal Form for File Names 83
Parity 89
PC-DOS 80
RECEIVE 84
Recognition 82
SEND 83
Wildcard 81
Table of Contents
10. PC-DOS and MS-DOS KERMIT-86 80
10.1. The MS-DOS File System 80
10.2. Program Operation 82
10.3. MS DOS KERMIT Commands 83
10.4. Installation 90
10.5. Adding Support for New Systems 94
Index 95