ptrepan1@umn-d-ub.D.UMN.EDU (pat trepanier) (10/26/89)
Here is the second part of the kermit docs.
--------------------------------cut here------------------------------
---------------------------------------
bline |
space bar |
openline |
---------------------------------------
Figure 1-1: VT100 Keypad on an Apple Keyboard
-------------------------------------------------------------------------------
similar to a VT52 keypad. Remember the open/closed Apple or the game button
must be pushed (like the cntl key) to get the keypad emulation. Figure 1-3
should clear up the questions.
1.5.16. the SHOW command
Syntax: SHOW [option]
The SHOW command displays various information:
ALL All parameter settings (this is quite long).
BAUD Baud rate of the com card.
CURSOR-KEYS-VT100 Are the cursor keys emulating the VT100 cursor
keys?
1.5.16. the SHOW command Page 18
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
PF1 PF2 PF3 PF4
------- ------- ------- -------
| | |findnxt|delline|
| CLEAR | = | / | * |
| gold | help | find |undelln|
------- ------- ------- -------
7 8 9 -
------- ------- ------- -------
| page |section|append |delword|
| 7 | 8 | 9 | + |
|command| fill |replace|undelwd|
------- ------- ------- -------
vt100 key ----> 4 5 6 ,
------- ------- ------- -------
vms edit usage ->| advanc|backup | cut |delchar|
gs key -------> | 4 | 5 | 6 | - |
vms edit usage ->| bottom| top | paste |undelch|
------- ------- ------- -------
1 2 3 ENTER
------- ------- ------- -------
| word | eol | char | |
| 1 | 2 | 3 | |
|chgcase|deleol |specins| |
------- ------- -------| enter |
0 . | ENTER |
-----------------------| sub |
| bline |select | |
| 0 | . | |
| openline | reset | |
-------------------------------
Figure 1-2: VT100 Keypad on an Apple//gs
-------------------------------------------------------------------------------
DEBUGGING Debugging mode.
DEFAULT-DISK Which Diskette drive is used for file transfer?
DEVICE-DRIVER Which communication device is being used?
DISPLAY Which screen display is being used?
ESCAPE Character for terminal connection.
FILE-TYPE Of Apple DOS/PRODOS file being sent/received.
FILE-WARNING Warn users if incoming file exists?
FLOW Should XON/XOFF flow control be used to the remote?
KEYBOARD II+ or //e keyboard.
1.5.16. the SHOW command Page 19
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
^ is up arrow BLUE RED GRAY ^ .(period) ENTER
------- ------- ------- ------- ------- -------
| | |delline| up |select | enter |
| 6 | 7 | 8 | 9 | 0 | - |
| gold | help |undelln|replace| reset | sub |
------- ------- ------- ------- ------- -------
v is down arrow 7 8 9 v
------- ------- ------- -------
| page |findnxt|delword| down |
| Y | U | I | O |
|command| find |undelwd|section|
------- ------- ------- -------
vt52 key ----> 4 5 6 ->
------- ------- ------- -------
vms edit usage ----> |advanc|backup |delchar| right |
apple key ----> | H | J | K | L |
vms edit usage ----> |bottom| top |undelch|specins|
------- ------- ------- -------
1 2 3 <-
------- ------- ------- -------
| word | eol | cut | left |
| N | M | , | . |
|chgcase|deleol | paste |append |
------- ------- ------- -------
0
---------------------------------------
bline |
space bar |
openline |
---------------------------------------
Figure 1-3: VT52 Keypad on an Apple Keyboard
-------------------------------------------------------------------------------
KEYPAD Does a gs keypad exist?
LOCAL-ECHO Full or half duplex switch.
PARITY Character parity to use
PREFIX Which default prefix to use with PRODOS?
PRINTER Should the printer be used for the display?
PROTOCOL Which protocol is to be used for file transfer.
RECEIVE Various parameters for receiving files
SEND Various parameters for sending files
SLOT Which slot # is communication device in?
1.5.16. the SHOW command Page 20
-------------------------------------------------------------------------------
TIMER Is the receive timeout on or off?
TIMING Count for timing loop
TERMINAL Which terminal (if any) should Kermit emulate?
The above options are analogous to the equivalent SET commands.
1.5.17. The STATUS Command
Syntax: STATUS
Give statistics about the most recent file transfer. This includes information
such as number of characters sent/received, number of data characters
sent/received, and last error encountered.
1.5.18. The TAKE Command
Syntax: TAKE filespec
The TAKE commands tells kermit-65 to execute commands from the specified file
similarly to the KERMIT.INIT file. See discussion on KERMIT.INIT above for
details.
1.5.19. The TYPE Command
Syntax: TYPE filespec
The TYPE commands tells kermit-65 to print to the screen from the specified
file. Text files only and works best with 80 characters per line or less.
1.5.20. The UNLOCK Command
Syntax: UNLOCK filespec
UNLOCK will unlock the given filespec on the default drive.
1.6. Installation
1.6.1. Standard Installation
To bootstrap Kermit to prodos, get the file APPPRO.BNS on a apple diskette.
Use binscii to convert this file into a shrinkit file. Use shrinkit to extract
the files onto a prodos diskette with your own prodos and basic.system files.
Then "-read.me" for further instructions. Thanks to Les Ferch for this install
system. For dos 3.3 get the files APP386.[1-2] on a master diskette then read
the first of app386.1 for further instructions. Thanks to Alan Kalker for this
install system.
The kermit binaries will run on either system. Simply use the PRODOS conver-
1.6.1. Standard Installation Page 21
-------------------------------------------------------------------------------
sion routines (if they have them fixed, better to use copy II+ or whatever) to
move kermit, kermit.help and kermit.init files. If you want other options as a
regular thing then you can change file kermit.init with your favorite editor.
Files Supplied for Kermit-65
The following files should be supplied on the columbia distribution tape:
APP386.1 Install system for dos 3.3 (1 of 2)
APP386.2 Install system for dos 3.3 (2 of 2)
APPAAA.HLP List of files (like this one)
APPAAA.NEW Whats new in this release
APPACC.HEX Apple com card hex
APPACC.M65 Apple com card source
APPCAT.HEX Apple cat hex
APPCAT.M65 Apple cat source
APPCCS.HEX CCS 7710 com card hex
APPCCS.M65 CCS 7710 com card source
APPCPS.HEX CPS com card hex
APPCPS.M65 CPS com card source
APPGS.HEX GS serial port hex
APPGS.M65 GS serial port source
APPHMM.HEX Hayes micro modem card hex
APPHMM.M65 Hayes micro modem card source
APPICON.BNS Kermit icon for gs users
APPLE.DOC Complete documentation (it says here)
APPLE.MSS Scribe text formatter source for documentation
APPLE.PS Documentation ready for a postscript printer
APPMAI.HEX Main kermit pgm hex
APPMAI.M65 Main kermit pgm source
APPMAK.UNX Make file for UNIX cross assembly (to assemble Kermit)
APPMSV.HEX Microtec com card hex
APPMSV.M65 Microtec com card source
APPPRO.BNS Install system for prodos
APPSSC.HEX Super serial com card hex
APPSSC.M65 Super serial com card source
APPXAS.1 65c02 cross assembler for UNIX system part 1
APPXAS.2 65c02 cross assembler for UNIX system part 2
APPXAS.3 65c02 cross assembler for UNIX system part 3
The syntax of the filenames may vary. On UNIX systems, the filenames will be
in lowercase. On VM/CMS systems, the period will be replaced by a space. All
files are text, however the suffix of BNS are binsciied binary files.
1.6.2. Alternate Installation
The main problem exists in getting the hex files onto your diskette as a text
file. But again that is a test of your creativity. If you have a version of
Kermit running then GET or RECIEVE the file as a text file and you are in busi-
ness. Since Kermit has been separated into two assemblies then two hex files
will have to be present on the diskette. Get the main hex file APPMAI.HEX and
select which com card hex you will need. First "exec APPMAI.HEX". Your Apple
(or compatable) will go into monitor and show you *'s for several minutes.
This is the monitor loading the hex into binary. If you get beeps from the
1.6.2. Alternate Installation Page 22
-------------------------------------------------------------------------------
monitor its probably because you didnt get a good copy of the text file. Now
EXEC the com card driver you are going to use. You will have to get back into
basic(aha another test for you, try "3d0G") to do this. And you will see the
monitor loading the com driver. The order of EXEC's is important. The com card
should be loaded last. Next get back into basic and do a "bsave
kermit,A$1000,L$7000". You may have to specify the drive to do this binary
save, with a slot or drive on the end of the BSAVE (aha another test). You now
run Kermit via "brun kermit".
If you want to customize Kermit for your needs, the recommended method is to
use file "kermit.init" OR do all your SETs, etc, and then do an "exit". Now
you should be back in BASIC. At this point do a "bsave name,A$1000,L$7000" and
when you do a "brun name" all your setups will be remembered. NOTE: If you
save your current settings via "bsave kermit ..." you may find that moving that
binary to another type of Apple (e.g. from a //e to an //e+) will not be pos-
sible. So make sure you keep the original binary to move between machine
types.
Since the org is now $1000 if you have been using Kermit and then went back to
basic for some trivial thing a "CALL 4096" should start up Kermit without
having to reload it.
In summary:
1. EXEC APPMAI.HEX
2. Choose the com card driver you will use. For example APPSSC.HEX.
3. 3D0G
4. EXEC APPSSC.HEX
5. BSAVE kermit,A$1000,L$7000
And you should be in business. Remember there is the command HELP and whenever
you are into a command a "?" will give you the possible options available at
that point of a command. The escape key will finish typing an option if it is
possible. The syntax of all the commands and options only requires enough
characters to make that command or option unique.
1.7. Problems
Installation
NOTE: When using the super serial driver you must have the cards sw6-2 on.
This allows the card to use interupts. The rest of the switches are set from
within Kermit. It appears that you can run your Apple 2 with sw6-2 on and in
99% of the cases will cause no problems. This is because the OS runs with in-
terupts locked out ("sei" in assembly language) and the program must explicitly
give a "cli" for interupts to work (the super serial driver does).
The AE Serial Pro must have switches 1 & 3 open and 2 & 4 closed. This appears
to dissagree with the documentation since those settings turn off irq interupts
and turn on nmi interupts. So watch this it may get corrected in later ver-
1.7. Problems Page 23
-------------------------------------------------------------------------------
sions.
The Microtek driver is a super serial look alike which does not run with inter-
upts. If you have trouble with the super serial driver you might try the MSV
driver. For you people with the MSV-622c card, you might try running a jumper
from the UART 6551 pin 26 to the card edge pin 30. This will enable interupts
just like the SSC sw2-6, and then you can use the super serial driver.
The Prometheus card will work with the Apple com driver. However you will have
to set the switches on the card for baud etc. Evidently this card can not be
programed by the software. If that is not true then here is an oportunity for
you to write a better driver. If you do please pass it on for other Prometheus
users.
The apple cat uses the modem's firmware for dialing. Type ";" for a 2 second
delay, or any control character to abort the dialing. ROM is not needed if ex-
ternal phone is used for dialing. Supports 110-600 baud, and 45.5 baud (use
kermit-65's 135 baud setting). Supports 1200 baud with apple-cat 212 card, in
slot-saver configuration. Allows use of external serial port by typing "X" as
dialing string. Thanks to Dick Wotiz for this driver. Reports have it that
the Apple Cat will also work with the Apple com driver.
Some have noted the Apple com card must be initialized via the "IN#x" before
starting Kermit. Ike has now updated this driver and the initialization is now
done within the Apple com driver. Thanks Ike.
Usage
There is the command HELP and whenever you are into a command a "?" will give
you the possible options available at that point of a command. The escape key
will finish typing an option if it is possible. The syntax of all the commands
and options only requires enough characters to make that command or option
unique.
When using flow control you may appear to hang. Type a ^Q (Control-Q) and that
may free you up.
Remember when you use your printer there are a lot of variables here. What was
being sent to the screen now is being sent to your printer. If you were
emulating the VT52 your printer may not know how to handle the escape se-
quences, tabs etc. It may be you can tell the host you are a tty or some such
device that will give carriage returns etc that your printer can handle. Some
printers may require the flow control and delay to get readable printing.
File Transfer Errors
"File Transfer Errors," was added to this document by the Southeast Regional
Data Center (SERDAC), '88 July 17.
In spite of the fact that successful Kermit file transfers are almost always
error free, there are a number of circumstances which can corrupt, prevent, or
interrupt/abort a transfer. In the case of an actual abort, there may be data
loss or corruption, and an incomplete file may not have a correct end-of-file.
These circumstances may be roughly divided into two groups: (1) problems due to
1.7. Problems Page 24
-------------------------------------------------------------------------------
file or disk errors, and (2) problems due to delays or failures in Kermit
packet exchange.
Common problems in category (1) include the following:
(a) improper file specification (b) wrong file type (c) protected file(s) (d)
disk problems
(1a) problems can occur when you specify, to either the Apple or host Kermit, a
non-existent or improperly located file. Misspelling and/or incorrect
(sub)directory specification are popular villains! If you are commanding ei-
ther Kermit to SEND a file (SEND filespec), the problem will be fairly obvious.
On the Apple II, you'll see an error message like: "FILE NOT FOUND." On the
VAX/VMS 8800, for example, you'll see the message: "%KERMIT32 ....., file not
found for 'filespec'". In either case, the transfer will not take place. If
you're using Kermit-65 to GET (GET filespec) files from the VAX/VMS Kermit
server, and the requested file does not exist in your VAX default directory,
you should see a Kermit-32 generated "REMOTE MESSAGE %KERMIT32 ....., file not
found for 'filespec'" appear in the transmission status display, and then the
Kermit-65 message "CANNOT RECEIVE FILE-HEAD". Transfer of the questionable
file will not take place.
(1b) problems can occur if you forget to specify, to either the Apple or host
Kermit, what type of file you wish to transfer. If you are using Kermit-65 to
send files to a host, you are fairly well protected against this error. If you
attempt to send a file whose CATALOG type does not match the FILE-TYPE
parameter setting, you will receive a "INCOMPATIBLE FILE FORMAT" error message,
or something similar, and the transfer will not take place. If, however, you
are receiving (via RECEIVE or GET) a file whose native type does not match the
FILE-TYPE setting, the file WILL be received. It will be mis-typed (according
to the FILE-TYPE setting), though, and any later attempt to use it on the Apple
will probably be unsuccessful.
The same sort of circumstances generally apply for a host Kermit. With the VAX
8800, for example, when Kermit-32 is sending a file, you generally need not
worry about setting its file type. When Kermit-32 is receiving a file,
however, properly setting its file type is very critical. If you wish to put
Kermit-32 in server mode to receive multiple files, set the file type BEFORE
using the SERVER command, and make sure that you only send it the appropriate
type of files during that server session. You cannot switch file types DURING
a given server session!
NOTE: One other way you can get into trouble with "wrong file type" is by try-
ing to send a file which is mixed-- mostly text, but with some imbedded charac-
ters that are not true 7-bit ASCII (i.e., ASCII codes 00-127). This often hap-
pens when you are trying to transfer a file which is word processor output.
Most word processing software claims to allow you to output a true ASCII or
text file, but in some cases it really does not, and in others the choice of
output options is confusing. If you have set up either Kermit program to
send/receive a text file, and you try to transfer illegal ASCII characters
(codes 128-256), your transfer may "hang" or be aborted. At the very best, if
the transfer "works," the suspect characters will later probably be meaningless
or confusing to the destination machine.
(1c) problems can occur in two ways on the Apple II. If your default drive
disk is write protected, and you attempt to receive a file, you will receive a
1.7. Problems Page 25
-------------------------------------------------------------------------------
"WRITE PROTECTED" error message, and no transfer will take place. If you have
set Kermit-65's FILE-WARNING parameter to OFF (normally NOT a good idea), and
you attempt to receive a file that already exists in a locked state on your
default diskette, you will receive a "FILE LOCKED" error message (if the file
is very short, you may have to check with a Kermit-65 STATUS command to see the
error message), and no transfer will take place.
Similar problems may occur on the host because of various file protection
schemes. On the VAX/VMS 8800, for example, Kermit-32 cannot send out a file
that you are unauthorized to read. And, it cannot receive a file unless you
are authorized to write to that filename and its (sub)directory. If you use
Kermit-32 to attempt to SEND (SEND filespec) a protected file, you should see a
"%KERMIT32 ....., insufficient privilege or file protection violation for
'filespec'" error message, and no transfer will take place. If you have
Kermit-32 in server mode, and you are trying to GET a protected file from it,
or you are trying to SEND it a file whose space is protected, you should see a
similar Kermit-32 generated REMOTE MESSAGE appear in the transmission status
display, and then, on GET, the Kermit-65 message "CANNOT RECEIVE FILE-HEAD".
Transfer of the protected file will not take place.
(1d) problems are most likely to occur because of Apple II diskette or drive
problems. The following conditions will generate "DISK I/O" or "I/O ERROR"
messages when Kermit-65 transfer commands are entered: bad diskette in default
drive, no diskette in default drive, default drive door open, and/or unINITial-
ized disk in default drive.
If any of those errors are detected before the attempted transmission of a
given file, the transfer of that file will not begin. If any are detected
DURING a file transmission, the file transfer will likely abort; at best trans-
mitted data will be incomplete. Data which does reach the destination end of an
aborted transfer should be considered very suspect; the disk problem should be
corrected and the transfer should be repeated! (The best chance you have for
salvaging text file data in an abort is if the file destination is the host
machine and you have told its Kermit to save incomplete files, e.g., on the
VAX-8800, you need to SET INCOMPLETE KEEP).
One other Apple II disk problem can be encountered while you are using
Kermit-65 to receive files. If you exceed the storage capacity of your diskette
during a RECEIVE or a GET, you should see a "DISK FULL" error message. Data
that has been received up to the point of the overflow will be automatically
DELETEd. Make CERTAIN that you do not try to receive any more files until you
have DELETEd some files from the problem diskette, or until you have replaced
it with one that has adequate capacity to receive the complete file. NOTE: See
Section 1.5.4.
It is less likely that (1d) problems would occur because of host machine disk
problems. The most likely circumstance you might encounter on the VAX/VMS
8800, for example, would be in receiving a large file and, in the process, ex-
ceeding your VAX disk quota. In such a case, you should see an appropriate
Kermit-32 generated REMOTE MESSAGE appear within the Kermit-65 transmission
status display. If this happens, delete some files from your VAX
(sub)directories, and/or have your VAX disk quota increased BEFORE you try the
transfer again. If you have issued a SET INCOMPLETE KEEP command to Kermit-32,
there may be some chance of salvaging text file data that arrived before the
disk quota overage, but the best thing you can do is to repeat the transfer!
As a general rule, if some disk or file error prevents a transfer from begin-
1.7. Problems Page 26
-------------------------------------------------------------------------------
ning, to get it to "go," you will need to correct the error and repeat all the
steps that preceded it.
If you are still commanding the host Kermit, and you see an error message, you
will have to get the host Kermit's prompt back and give it an acceptable com-
mand. If you have commanded the host Kermit to SEND or RECEIVE, and are back
commanding Kermit-65 when you notice the error, you will have to correct the
problem, CONNECT back to the host, get the host Kermit prompt (with the VAX/VMS
8800, try typing RETURN or CTRL-Y), and repeat the SEND or RECEIVE command, be-
fore returning back to Kermit-65 to command it again.
If you have placed the host Kermit in server mode, and are giving Kermit-65
commands when you notice an Apple disk/file error prevents a file transfer from
starting, chances are good that you won't have to CONNECT back to the host. It
is also important to note that within a single server session, when you are
transferring multiple files, all files transferred PRECEDING an error (or
abort) are probably good. To repeat the transfer, correct the error, and give
Kermit-65 the appropriate command to transfer the file that messed up. The
first time you do it, you may get back a message like "REMOTE MESSAGE
%KERMIT-32..... protocol error" This is just the host server trying to get back
"on track" after the error. When the Kermit-65> prompt returns, enter the
transfer command again, and it will probably be accepted.
If the second attempt should fail, wait for the Kermit-65> prompt, enter:
FINISH, wait for the prompt again, and enter: CONNECT. If you do not see the
host operating system prompt ($ on the VAX 8800), type a few RETURNs (or on the
VAX/VMS a CTRL-Y). Re-invoke the host Kermit and put it back in server mode.
If disk or file errors prevent a transfer from completing, recovery will depend
on the error, whether you had the host Kermit in server mode or not, and on
your desire for accuracy.
Some disk/file error aborts are "fatal" (e.g., Apple DISK FULL, and uploading
to the VAX 8800 w/o having commanded Kermit-32 to SET INCOMPLETE KEEP). The
destination file will be destroyed. The transfer of the file will have to be
repeated again from the beginning. Again, unless you have set the host Kermit
for server mode, you will have to CONNECT back, get the host Kermit prompt, and
re-command it. If you were in a server session, though, you can probably
repeat the transfer of the interrupted file without going back to the host (see
recovery procedures above).
Other disk/file errors that interrupt/abort a transfer may leave salvageable
text data at the transfer destination. The best policy, though, is to repeat
the transfer of the incomplete file (see recovery procedures above).
Common problems in category (2) include the following:
(a) bad parity
(b) noisy communications line
(c) timeout due to delays, "disaster," etc.
(d) Kermit-program incompatibility
(e) user error
1.7. Problems Page 27
-------------------------------------------------------------------------------
(2a)
Parity settings are very critical to correct transfers. If you do not inform
Kermit-65 of the correct parity being used by the remote host machine or the
communications path to it, "checksum" error checking calculations will be
wrong, and packets will be consistently rejected when they arrive at their des-
tination. In particular, most binary file Kermit transfers won't get very far
if parity is not set correctly.
[NOTE: If you want to do a binary file transfer (Apple binary or BASIC files)
via a FIRN Network connection to the SERDAC VAX/VMS 8800, you must SET PARITY
SPACE before the transfer is initiated; that will insure that eight-bit quoting
is used. If you dial directly into the VAX/VMS 8800, SET PARITY NONE;
eight-bit quoting (which is less efficient) is not required].
(2b)
Line noise can be the root cause for a variety of file transfer problems. The
beauty of a "packetized protocol transfer" scheme like Kermit is that or-
dinarily, the scheme will overcome an occasional burst of line noise. A packet
which arrives out of sequence, or which does not have the same checksum "bit
count" as when it was sent, will get retransmitted, and the noise induced data
error will correct itself.
Sometimes, however, bad line noise can outwit even the cleverest aspects of
Kermit. There are some times where severe noise can corrupt the "checksum" er-
ror checking and lead to undetected transmission of a bad character (assuming
that the severe line noise exists, chances of this happening for one character
are, for Kermit-65 error checking, less than two percent).
If line noise is bad enough and persistent enough, it is also a cause for
several problems that will eventually "hang" or totally confuse and abort a
transfer:
Each transfer is preceded by the Kermit-to-Kermit exchange of several short
"initialization packets. These tell the controlling programs critical things
to expect about the upcoming transfer. If line noise prevents the packets from
arriving, or scrambles them up, the transfer probably can't get started cor-
rectly.
One of the biggest vulnerabilities of the Kermit scheme is that each arriving
packet must be acknowledged (ACK) by the receiver, and that the sender must ac-
tually receive back the acknowledgement (likewise, if an expected packet does
not arrive, there often must be a negative acknowledgement (NAK)). Since the
ACK/NAK packets are very short, they are rather vulnerable to severe noise. If
too many of them are scrambled or lost, the transfer can get out of synch, and
the transferring programs can lose track of where they are.
One other place Kermit is vulnerable is in the beginning of a data packet. The
first several bytes of these longer packets are reserved for control infor-
mation: packet type, byte count, sequence number, etc. If line noise
repeatedly coincides with the transmission of this control information, it is
very easy for the transfer to get confused-- particularly if the packet number-
ing gets garbled.
If you detect frequent line noise after you've connected to a host, but before
1.7. Problems Page 28
-------------------------------------------------------------------------------
you begin transfers (you will probably see extraneous junk characters appearing
on your screen), you're probably in for trouble. Once transfers actually begin,
line noise problems are often characterized by incrementing of the RETRY
counter on the Kermit-65 transmission status display, and/or by long pauses in
incrementing of the status display byte counter.
To minimize line noise, first see if there are any obvious loose connections in
your equipment (telephone line connection to wall box, telephone line to modem,
modem cabling to serial connector, or, if appropriate, cabling from hardwire
port to serial connector). If not, you may want to hang up and redial to get
another telephone connection (almost every connection is unique, and you may
get a better one than you had). Many line noise problems will clear up with
those simple remedies, but some may be beyond your control!
If all else fails, you may also try shortening the maximum length of your data
packets (SET SEND/RECEIVE PACKET-LENGTH) to possibly lessen the effects of per-
sistent noise.
(2c)
A Kermit transfer consists of a regular and predictable exchange of initializa-
tion, data, and, ACK/NAK packets. If something (line noise, busy computer,
user error, etc.) interrupts or delays this regular exchange, there must be a
way for a Kermit program on at least one end to figure out something is wrong
and try to get the packet exchange back on track again.
This is usually done with a timer and retry mechanism. If a Kermit does not
receive an expected packet, within its timer's time limit (a timeout), it will
resend its last sent packet to try to "wake up" the other Kermit (effectively
by asking it to send its last packet again). This resending is repeated
("retried") a number of times before the program assumes it cannot get things
on track again. Each packet resent by Kermit-65 is counted as a RETRY on its
transmission status display. If Kermit-65's retry count exceeds 20, it will try
to issue an error message according to what kind of packet it was waiting for
and/or it will say MAX RETRY COUNT EXCEEDED. The transfer will then be aborted.
Very frequently, timeouts are caused by unexpected delays in the remote com-
puter, or in the network thru which you connect to it. If you know that the
host machine or network is very busy, and you repeatedly have aborted transfers
due to timeouts, you may be able to alleviate the problem by increasing the
value of the default Kermit-65 receive timeout parameter (SET RECEIVE TIMEOUT).
Other common ways that Kermit-65 can timeout and abort are: (1) if the host
machine "goes down" during a transfer, (2) if the telephone, network, or
hardwire connection is completely broken during a transfer, (3) if you forgot
to "start up" the host Kermit and give it a transfer command (SEND, RECEIVE, or
SERVER) BEFORE giving Kermit-65 a transfer command, and (4) if (2a), (2b),
(2d), or (2e) problems occur and critical initialization packets are never
received.
In cases (1) and (2), you will eventually probably see a CANNOT RECEIVE DATA or
MAX RETRY COUNT EXCEEDED message from Kermit-65. Cases (3) and (4) may result
in a CANNOT RECEIVE INIT message.
(2d)
To do effective Kermit transfers, there must be two Kermit programs working--
1.7. Problems Page 29
-------------------------------------------------------------------------------
one on either end of a "computer connection." In addition, the two Kermits
must be able to "talk to" each other in a prescribed, standard way. Although
there are specific standards for writing all Kermit programs, most of them have
been written by volunteers and are in the "public domain." The protocol re-
quirements and resultant programs are generally rather complex, and it is all
too easy to inadvertently program in a subtle error in a given Kermit version.
Additionally, there are many "levels of ability" of Kermit programs: some can
operate in server mode, some cannot. Some can transfer binary files; some can-
not, etc. Unless the Kermit programs you are using are both error free, and
both have the same capabilities for the transfers you wish to perform, you are
in trouble!
If there is a systematic "bug" in one of the Kermit programs, or if you are as-
king one Kermit to do something the other can't do, there will usually be a
problem with packet exchange; in many cases the requested transfer will not
even get started. You may see a Kermit-65 error message, on the transmission
status display, saying that a packet was not received, or a REMOTE MESSAGE say-
ing a packet was unexpectedly received, or one that the command cannot be ex-
ecuted by the other Kermit. In some cases, you may see no explanatory error
messages at all; the transfer will just "hang" and will probably eventually
"timeout" and abort (MAX RETRY COUNT EXCEEDED).
(2e)
If you've read about category (1) errors above, you can see that there are a
variety of things you can do to with files or disks to mess up a Kermit trans-
fer. You can also wreak havoc by issuing improper or illegal commands to Ker-
mit programs. Before trying to transfer a lot of files, or trying out a new
type of transfer, be sure you understand the procedure you need to follow and
the various Kermit commands that will be involved.
New Kermit users often try to command their local Kermit program (e.g.,
Kermit-65) to send or receive a file, without having first invoked and com-
manded the host Kermit.
Another common error is to issue improper commands to a remote server. For ex-
ample, when VAX/VMS Kermit-32 is in server mode, and you are requesting files
from it via Kermit-65 commands, you cannot use a RECEIVE command; you must in-
stead use GET.
As with Kermit program incompatibilities, illegal or inappropriate commands
will often cause a problem with packet exchange; in many cases the requested
transfer or action will not even get started. You may see a Kermit-65 error
message, on the transmission status display, saying a packet was not received,
a REMOTE MESSAGE that a packet was unexpectedly received, or one that the com-
mand cannot be executed by the other Kermit. In some cases, you may see no ex-
planatory error messages at all; the transfer will just "hang" and will prob-
ably eventually "timeout" and abort (MAX RETRY COUNT EXCEEDED).
Except for the fact that you will probably never note a category (2) "packet
exchange" error while you are "talking to" the remote system or commanding its
Kermit, and that the remedies you must employ to correct the errors will be
different, recovery procedures to get your file transferred correctly will be
much the same as those we described at the end of the discussion on category
(1) "disk/file" errors. Make sure to read that discussion for more details
than we have included below.
Apple II Kermit Page 30
-------------------------------------------------------------------------------
In short, if an error prevents a given transfer from actually beginning, you
will need to correct the error and repeat all the steps that preceded it. This
will be more difficult if you are transferring only one file-- having commanded
the remote Kermit to SEND or RECEIVE. If you have placed the remote Kermit in
server mode, and an error prevents the transfer of one file, all files trans-
ferred up to that point are probably OK, and you can usually correct the
problem, and get a transfer started again without having to reCONNECT back to
the host.
If you are transferring a text file, and an abort occurs in mid-transfer, some
data may be salvageable in the destination file, but the best rule with any
type of file is to repeat the transfer, in which case the recovery procedures
in the last paragraph apply.
1.8. Customizing Kermit-65
The source code to Kermit-65 is in 6502 Assembler. It has been formatted for a
cross assembler which runs on a unix 2's complement machine. Files appxas.1
thru appxas.3 are the cross assembler for UNIX. Get the files on a UNIX system
and then look at the documentation at the start. They will easily make you a
xasm for Kermit. The file appmak.unx is the makefile to use with the xasm to
reassemble all of Kermit's parts.
Kermit-65 has been separated into two assemblies, the main routines and the com
card routines for the devices shown in Table 1-1. A vector has been set up in
low memory for the two assemblies to communicate. Look at the working com
drivers for tips on how to incorporate your version of the com driver. some
things to note: It is probably best to buffer the input from the remote and to
get input characters from the remote every chance you get. Note the Microtek
SV-622 driver, whenever the input is checked for a character and has a charac-
ter the character is put into the buffer immeadiatly. Also when the output is
checked for ready to output, if the card is not ready to output then it is
checked for a character to input. All this should help prevent losing charac-
ters.
All the routines should return with the "rts" instruction. Routines which can
return a true/false indication should return with the P reg zero flag set ap-
propiately. That is: a "beq" instruction will branch on a false indication and
the "bne" will branch on a true indication. The com driver should start its
routines above the main routines and tell where the end of the com driver is
via location $100c. If your com driver gets too large then the bsave address
would have to be changed when you are saving the binary to diskette.
Apple II Kermit Page 31
-------------------------------------------------------------------------------
address size module function
1003 byte main This is the baud rate index as follows:
3 - 110
4 - 135.4
5 - 150
6 - 300
7 - 600
8 - 1200
9 - 1800
10 - 2400
11 - 3600
12 - 4800
13 - 7200
14 - 9600
15 - 19200
eg:if index is 6 then line should be 300 baud
1004 byte unused
1005 word driver Address of a null terminated string.
address should point to a capitalized
string of the drivers id
1007 byte main Com slot in the form $n0 where n is slot #.
1008 byte main Force initialization flag when 0.
init routine should always initialize when
this flag is 0 & then set flag non-zero.
1009 word main Address of the end of Kermit main routine.
100b byte main Flow control is on when high bit is set.
100c word driver Address of the end of the com driver.
1020 3 bytes driver Jump to initialization routine.
1023 3 bytes driver Jump to command routine. A reg has command
0 - hang up the line
$0b - set baud rate
$0c - set break on the line
$91 - do xon on the line
$93 - do xoff on the line
routine returns false (P reg zero flag) if unable
1026 3 bytes driver Jump to check for input from the line.
routine returns false (P reg zero flag)
if no character on line
1029 3 bytes driver Jump to get input character from line.
routine returns character in A reg
102c 3 bytes driver Jump to put character in A reg on line.
102f 3 bytes driver Jump to reset com driver.
1040 3 bytes main Jump to Apple ROM wait rtn. microsecs delay
=1/2(26+27A+5A*A) where A is the accumulator
1043 3 bytes main Jump to routine to print null-terminated string.
X reg contains least significant byte of address
Y reg contains most significant byte of address
routine does not issue a carriage return.
1046 3 bytes main Jump to routine to read the keyboard.
A reg contains the character read
1049 3 bytes main Jump to routine to print carriage rtn & line feed.
104f 3 bytes main Jump to routine to set characters parity.
A reg contains the character before and after.
Table 1-4: Communications card vector area
Apple II Kermit Page 32
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
List of most of the prodos file types.
Num Name OS Definition
$00 typeless
$01 BAD both BAD blocks file
$02 PCD SOS Pascal CoDe file
$03 PTX SOS Pascal TeXt file
$04 TXT both ASCII text file
$05 PDA SOS Pascal DAta file
$06 BIN both BINary file
$07 CHR SOS CHaRacter font file
$08 PIC both PICture file
$09 BA3 SOS Business BASIC (SOS) program file
$0A DA3 SOS Business BASIC (SOS) data file
$0B WPD SOS Word Processor Document
$0C SOS SOS system file
$0D SOS SOS reserved file type
$0E SOS SOS reserved file type
$0F DIR Both subDIRectory file
$10 RPD SOS RPS data file
$11 RPI SOS RPS index file
$12 SOS Applefile diskcard file
$13 SOS Applefile model file
$14 SOS Applefile report format file
$15 SOS Screen library file
$16 SOS SOS reserved file type
$17 SOS SOS reserved file type
$18 SOS SOS reserved file type
$19 ADB ProDOS AppleWorks Database file
$1A AWP ProDOS AppleWorks WordProcessing file
$1B ASP ProDOS AppleWorks Spreadsheet file
$1C-$5F Reserved
$60-$6F ProDOS PC Transporter (Applied Engineering)
$60 PRE ProDOS ProDOS preboot driver
$61-$6A ProDOS Reserved
$6B NIO ProDOS PC Transporter BIOS and drivers
$6C ProDOS Reserved
$6D DVR ProDOS PC Transporter device drivers
$6E ProDOS Reserved
$6F HDV ProDOS MSDOS HardDisk Volume
$70-$9F Reserved
$A0 WPF ProDOS WordPerfect document file
$A1 MAC ProDOS Macrofile
$A2 HLP ProDOS Help File
$A3 DAT ProDOS Data File
$A4 Reserved
$A5 LEX ProDOS Spelling dictionary
$A6-$AB Reserved
Table 1-5: PRODOS file types, part 1
-------------------------------------------------------------------------------
Apple II Kermit Page 33
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Num Name OS Definition
$AC ARC ProDOS General Purpose Archive file
$AD-$AF Reserved
$B0 SRC ProDOS ORCA/M & APW source file
$B1 OBJ ProDOS ORCA/M & APW object file
$B2 LIB ProDOS ORCA/M & APW library file
$B3 S16 ProDOS ProDOS16 system file
$B4 RTL ProDOS ProDOS16 runtime library
$B5 EXE ProDOS APW shell command file
$B6 STR ProDOS ProDOS16 startup init file
$B7 TSF ProDOS ProDOS16 temporary init file
$B8 NDA ProDOS ProDOS16 new desk accessory
$B9 CDA ProDOS ProDOS16 classic desk accessory
$BA TOL ProDOS ProDOS16 toolset file
$BB DRV ProDOS ProDOS16 driver file
$BC-$BE Reserved for ProDOS16 load file
$BF DOC ProDOS document file
$C0 PNT ProDOS //gs paint document
$C1 SCR ProDOS //gs screen file
$C2-$C7 Reserved
$C8 FNT ProDOS Printer font file
$C9 ProDOS finder files
$CA ProDOS finder icons
$CB-$DF Reserved
$E0 LBR ProDOS Apple archive library file
$E1 Unknown (unlisted)
$E2 ATI ProDOS Appletalk init file
$E3-$EE Reserved
$EF PAS ProDOS ProDOS Pascal file
$F0 CMD ProDOS added command file
$F1-$F8 ProDOS User defined filetypes
(popular ones include:)
$F1 OVL ProDOS Overlay file
$F2 DBF ProDOS Database file
$F3 PAD ProDOS MouseWrite file
$F4 MCR ProDOS AE Pro macro file
$F5 ECP ProDOS ECP batch file
$F6 DSC ProDOS description file
$F7 TMP ProDOS temporary work file
$F8 RSX ProDOS linkable object module
$F9 IMG ProDOS ProDOS image file
$FA INT ProDOS Integer BASIC program
$FB IVR ProDOS Integer BASIC variables file
$FC BAS ProDOS AppleSoft BASIC program
$FD VAR ProDOS AppleSoft BASIC variables file
$FE REL ProDOS ProDOS EDASM relocatable object module file
$FF SYS ProDOS ProDOS8 system file
Table 1-6: PRODOS file types, part 2
-------------------------------------------------------------------------------
Apple II Kermit Page 34
-------------------------------------------------------------------------------
Index
Apple II 1 REMOTE Command 10
Apple II Keypad 14, 16 RENAME Command 10
Apple II+ keyboard 7
Applesoft 13 SEND Command 10
Archiving files 3 SERVER Command 11
SET APPLICATION-MODE 11
Backspace key 15 SET BAUD 12
Binary 13 SET Command 11
Blink 7 SET CURSOR-KEYS-VT100 12
SET DEBUGGING 12
CA key 16, 17 SET DEFAULT-DISK 12
CATALOG Command 6 SET DISPLAY 12
CONNECT Command 6 SET ESCAPE 12
Control-c 11 SET FILE-TYPE 13
SET FILE-WARNING 13
Del key 15 SET FLOW 13
Delay 9, 13, 16 SET KEYBOARD 14
DELETE Command 8 SET KEYPAD 14
Dos 2 SET LOCAL-ECHO 14
Dos filenames 2 SET PARITY 14
SET PREFIX 14
Escape character 9 SET PRINTER 15
EXIT Command 8 SET PROTOCOL 15
SET SLOT 15
Game button 16, 17 SET SWAP 15
GET Command 8 SET TERMINAL 16
SET TIMER 15
HELP Command 9 SET TIMING 16
SHOW command 17
Install 20 Smart modem 9
Integer 13 STATUS Command 20
Kermit 15 TAKE Command 20
Kermit.help 21 Text 13
Kermit.init 21 TYPE Command 20
KERMIT.MODEM 9
UNLOCK Command 20
LOCK Command 9
LOG Command 9 Vt100 16
VT100 Emulation 16
MODEM Command 9 Vt52 16
Monitor 16 VT52 Emulation 16
OA key 16, 17 Xmodem 10, 15
Other 13
Prodos file system 4
Prompting 6
Q 8
Readme 20
RECEIVE Command 10
Apple II Kermit Page i
-------------------------------------------------------------------------------
Table of Contents
1. Apple II Kermit 1
1.1. Supported Systems and Devices 2
1.2. The DOS 3.3 File System 2
1.3. The PRODOS File System 4
1.4. Program Operation 4
1.5. Kermit-65 Commands 6
1.5.1. The CATALOG Command 6
1.5.2. The CONNECT Command 6
1.5.3. The DELETE Command 8
1.5.4. The EXIT and QUIT Commands 8
1.5.5. The GET Command 8
1.5.6. The HELP Command 9
1.5.7. The LOCK Command 9
1.5.8. The LOG Command 9
1.5.9. The MODEM Command 9
1.5.10. The RECEIVE Command 10
1.5.11. The REMOTE Command 10
1.5.12. The RENAME Command 10
1.5.13. The SEND Command 10
1.5.14. The SERVER Command 11
1.5.15. The SET Command 11
1.5.16. the SHOW command 17
1.5.17. The STATUS Command 20
1.5.18. The TAKE Command 20
1.5.19. The TYPE Command 20
1.5.20. The UNLOCK Command 20
1.6. Installation 20
1.6.1. Standard Installation 20
1.6.2. Alternate Installation 21
1.7. Problems 22
1.8. Customizing Kermit-65 30
Index 34
Apple II Kermit Page ii
-------------------------------------------------------------------------------
List of Figures
Figure 1-1: VT100 Keypad on an Apple Keyboard 17
Figure 1-2: VT100 Keypad on an Apple//gs 18
Figure 1-3: VT52 Keypad on an Apple Keyboard 19
Apple II Kermit Page iii
-------------------------------------------------------------------------------
List of Tables
Table 1-1: Apple II Communication Cards Supported by Kermit-65 2
Table 1-2: Kermit-65 Single-Character CONNECT Escape Commands 7
Table 1-3: Apple II/II+ Keyboard Escapes 8
Table 1-4: Communications card vector area 31
Table 1-5: PRODOS file types, part 1 32
Table 1-6: PRODOS file types, part 2 33