Programmer 7500/MAX_PROGRAMMERS.iso/PASCAL/ITERM.ZIP/ITERM.DOC

Text File | 1986-01-26 | 7.9 KB | 160 lines

ITERM.COM by Scott Murphy

77 So. Adams St. #301

Denver, CO 80209

Compuserve 70156,263



   ITERM.COM is a terminal emulator for the IBMPC and close

compatibles.  It supports a telephone directory and auto-dial

for a Hayes external modem.  ASCII files can be transmitted and

received with X/ON-X/OFF flow control, or files of any kind may

be sent and received using the XMODEM-CRC protocol. Because it

is written in Turbo Pascal, and because it does not include

every concievable feature, it is relatively small (25K), and

loads and executes quickly.  Its only known bug that I have been

unable to root out is a frequent failure to initialize the modem

correctly when first executed. Exiting and re-running the

program invariably solves the problem.



   ITERM is essentially "modeless."  Everything you type at the

keyboard, with the exception of the alt-shifted command keys

described below, is sent to the modem and on to the machine you

are communicating with.  I find this simplicity attractive

compared to older CP/M programs, or the implementation of

KERMIT that I have used.



Status Line

   ITERM maintains a dispaly of its current status on the top

line of the screen. If you wonder what's going on, look there-

it probably says.



Auto-Dialing

   ITERM maintains a directory of 20 telephone numbers.  Each

directory entry has room for the name of the system, your

usercode and password, the communication parameters needed by

the remote system, and a list of characters to be filtered from

the incoming stream.  ITERM will look for its directory file on

the currently logged disk.  If none is present, a new, blank

directory is created.  It is up to you to fill in the directory

as you use the program.



Command Keys



F1 ------ Send the current usercode string.

F2 ------ Send the current password string.

F3 ------ Recall the last line typed at the keyboard.

F7 ------ Send an ASCII file with X/ON - X/OFF flow control.

F9 ------ Toggle ASCII text capture on/off. The first time you

          use F9, you will be prompted for a filename to open and

          use for text capture. If the file exists, text will be

          added to the end of the file. X/ON - X/OFF flow control

          is used.

F10 ----- Close the current text capture file, and turn text capture off.

Alt-B --- Break. Sends a break signal to the remote system.

Alt-C --- Clear the screen.

Alt-D --- Dial the modem. A numbered list of system names will

          appear in a window on the screen. To dial a system,

          enter its line number (1-20), and a carriage return.

          To add, or change an entry, enter the letter 'C' and

          a carriage return. You will be prompted for a line

          number to add or change.  You will be prompted for

          the contents of the directory entry interactively. If

          you don't wish to change an item of the directory entry,

          just type a carriage return.  Some mainframes _will_

          persist in adding junk characters to their output stream.

          You may filter these out by providing their decimal ASCII

          codes at the appropriate prompt. (127, the little house-

          shaped pictograph on IBM is a common one.) Some machines cannot

          accept the strings sent by the F1, F2, and F3 keys at the

          full speed of your modem. By default, ITERM waits for an

          echo from the remote system before sending each new character.

          You may defeat this by answering no at the 'Use pacing' prompt.

          If you decide not to dial a number or change an entry,

          answer the first prompt with a single carriage

          return.  If you wish to abort a call in progress,

          (perhaps because of a busy signal) type a control-X.

Alt-H --- Hang-up the modem. This command tells the modem that

          the terminal (your computer) is no longer ready to

          talk to a remote system. The modem responds by

          hanging up. In its default configuration, the Hayes

          modem maintains the Terminal-Ready state regardless

          of what ITERM tells it. To enable the Alt-H command,

          you must disable this feature of the modem. (Switch 1

          inside the front panel of the Smartmodem 300 must be

          UP to enable Alt-H. Settings for other models and

          compatible brands will vary. Consult your manual.)

Alt-P --- Parameters. Alter or examine the current

          communication parameters.  Allows you to see or set

          the baud-rate, number of stop-bits and data bits, and

          the parity setting.  The program will gladly accept

          any baud rate up to 9600. It's up to you to enter the

          desired rate without typos.

Alt-R --- Recieve a file in XMODEM-CRC protocol. You will be

          prompted for a filename. If the file exists, you have

          the option of overwriting it or entering a new file

          name.

Alt-S --- Send a file in XMODEM-CRC protocol. You will be

          prompted for a file name to send. If it cannot be

          found, you may retype the name, or abort the send.

          Once the transmission process has begun, you may

          abort it at any time by typing a control-X.

Alt-X --- eXit ITERM.  You can back out of the exit if you

          issue this command by mistake.  (Note: ITERM will not

          automatically hang up the modem on exit. This can be

          useful if you wish to run other software and then

          return to your session.)

Home ---- Help. Displays a menu of commands.



Up

Arrow --- Saves the contents of the current screen for later

          review.

Down

Arrow --- Restores the contents of the screen saved with Up

          Arrow.

Right

Arrow --- Recalls characters from the last line typed at the

          keyboard, one at a time.





Notes on the source code.

   ITERM is composed of code I have written in Turbo-Pascal,

   and of code others have written and released to the public

   domain.  I hereby release the portions I wrote into the

   public domain as well.  You may do anything with it except

   put your name on it and attempt to sell it for profit.

   Remember, there is no creature more despicable than a

   plagiarer!



   ITERM is composed of a "root" file, ITERM.PAS, and a set of

   ".INC" files that implement various sections of the program.

   Turbo Pascal permits the type definitions, and constant and

   variable declarations of a program to be scattered through-

   out a source file, so long as they appear outside the block

   where they are used. I have taken advantage of this feature

   to keep the Type, Const, and Var sections of the various

   include files near the code that uses them.



   The include files are as follows:

        ITRMDIAL.INC -- implements auto-dialing and the phone

          directory.

        ITRMSAVE.INC -- the code to capture the ASCII text of

          your terminal section.

        ITRMXFER.INC -- implements XMODEM protocol and ASCII

          text-file transmission.

        ITRMMISC.INC -- miscellaneous service routines used by

          other program segments.

        ITRMPORT.INC -- the routines that drive the serial

          port, including the interrupt service routine that

          permits interrupt driven input from your modem. Most

          of these routines were written by Alan Bishop.

        ITRMWIND.INC -- the routines that handle the windows

          that come and go as the program runs, and allow you

          to save a screen for later reference. Thes were

          written mostly by Bela Lubkin of Borland Int'l.



Your comments or complaints, and especially your improvements,

are of course, invited.



Unsolicited Advertisement: Turbo Pascal, and Borland International,

its publishers, are a joy to work with.  Seek them out.