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******************************************************************************* IBM ASYNCHRONOUS COMMUNICATIONS SUPPORT PROGRAM MODIFICATIONS BY ROBERT C. RICE PROGRAM DESCRIPTION ******************************************************************************* The IBM Asynchronous Communication Support Program provides software needed to allow the Personal Computer to communicate with a wide variety of computer systems including several IBM mainframe computers. While emphasizing great flexability in communications and providing a protocol for file transfer be- tween Personal Computers, the Asynchronous Communications Support Program lacks a number of features required by the average user. Uploading and Down- loading files to and from commercial computer networks such as the SOURCE and CompuServe is an example. Additionally, the user must be technically competent in communications protocol to be able to properly set selectable parameters provided through various menus. User friendly design has been substantially ignored. Also, a programming error prevents proper use of the backspace key. This Program Description provides information about changes that I have made to my version of the IBM Asynchronous Communications Support Program, correct- ing errors, providing enhancements, improving user friendliness, and eliminat- ing unnecessary entries. The following is an overview of the enhancement program. Each feature will be discussed in detail later in this paper. 1. A 64K version named SHORTERM.BAS, and a 96K version named LONGTERM.BAS. 2. Correction of the backspace problem. 3. Elimination of width question, automatic selection of screen width and an option to bypass all intermediate menus, going directly into full duplex operation. 4. Additional preselected parameters for Display Selection and Dialing Option for the Hayes Smartmodem.(Use of displays and Autodial modem is optional.) 5. Addition of "terminal type" for "Starting as" or "Returning as" printouts to eliminate any question as to what terminal was selected. 6. Download capability, including error trapping, file directory printout, On/Off switching of data recording for open files, and status indicator. 7. Upload capability, including error trapping, file directory printout, On/Off switching, status indication. 8. Time/Date/Status line. The right side of line 25 used to display time, date (if entered), Hex Listing, Printer, Upload, and Download status symbol display while operating as a terminal. 9. Extended use of function keys including F5 to call up Function Key help menu. F7 to turn printer On/Off. F8 for Telephone/LOG-ON menu and functions. F9, an Upload On/Off switch. F10, a Download On/Off switch. Also use of ALT P to print maximum receive buffer used. ALT H to display Telephone/LOG- ON help menu. And in the 96K version ALT S for Half Duplex force to SENDING state. 10.Telephone/LOG-ON menu and function. Designed primarily for, but not limited to use with the Hayes Smartmodem. Selected numbers are automa- tically dialed, and all LOG-ON entries are made using the F8 key. 11.When XON/XOFF supported the automatic suspension of input when F2 function selection menu is entered by sending XOFF and when returning to terminal operation, automatic resumption of transmission by sending XON. 12.Automatic enabling of error messages upon terminal startup and elimination of input parity detection to eliminate unnecessary and excessive error mes- sages. 13.Error trapping routines supported in many, but not all areas for printer applications. 14.Use of F5 function key when returning from BASIC. (Function menu item#3) instead of having to type continue. 15.Two new function selections to exit the Communications Program, including warning messages with verification of program termination. The exit routines also including "COM1:" close-out to prevent program hangup. 16.Changes to preset terminal parameters, facilitating program initialization in full duplex mode and the bypassing of intermediate menus. I must acknowledge the assistance of Morris E. Thompson of Dallas, Texas in this effort, since he supplied the final versions of the backspace fix and the original versions of the Upload/Download that are contained in the follow- ing program. I must also acknowledge the fine people connected to the SOURCE and John Lamond, a SOURCE representative, for giving me needed information which I used to develop this program. There are four documents which support these program modifications. First, this paper describes the functional changes that were made to the program and provides a reference document for program operation. Second, Program Notes have been provided to assist you in understanding the changes and so that you may properly adapt the program for your use. Third, there is a Tutor- ial, showing you how to use the program. Fourth, the actual program which you will use to modify the original IBM program. The Functional Description is as follows: 1) There are two versions of the program modifications. The first is a 64K version designed to fit into the same amount of memory as was required for the original program. This version has the VM370, TSO, and Half Duplex support removed so that other more useful program features could be incor- porated. This version also requires changes to the AUTOEXEC.BAT file which is executed when you load the diskette. Since BASIC does not use a random file, or its own communications buffer, additional memory is freed by setting the random file buffer and communications buffer to a minimum setting. This change must be made, otherwise an OUT OF MEMORY error will occur. A 96KB version is also provided so that users with the proper amount memory will have all capabilities from the original program included as well as all of the program enhancements. This is done by relocating the machine code RS232 interrupt handler into the memory segment above the 64K used by BASIC. 2) The original IBM program did not properly backspace when the backspace key was depressed. A fix was provided which corrects the problem and allows for full utilization of the backspace key. 3) Each time the program was loaded or the "Return to terminal Selection" was invoked from the function menu, the question was asked whether you wanted 40 or 80 character screen width. This is a determination that should be made once when you first use the program but not each time. This modifi- cation allows you to adapt a 40 or 80 character screen width for color video monitors when you get the program, then after the screen width is automatically set depending upon whether the monochrome display or the color graphics adapter is being used. In place of the question about width is the question "Bypass intermeditate menus (y/n)?". Parameters have been preselected in this program for proper use with the SOURCE and other like computer networks. It is therefore unnecessary to go through a terminal selection every time you use the program. Answering "Y" or yes to this question will allow you to go directly into operation as a full duplex terminal. This value may be adapted to other terminal selections so that users with special applications may also avoid having to go through the selection menu except on special occaisions. Answering "N" or no to the question will allow you to go through the terminal selection menu as the original program does now. For people with varied applications, I suggest that you make several copies of the program, each with a preset terminal configuration, this way you may also avoid all the terminal selections each time you use a different application. (preset values are fully des- cribed in the Programming Notes section.) When screen width is determined the program title lines are properly centered on the screen regardless of width setting. The program title has also been changed to indicate the program version, and acknowledge contributers. 4) Two additional parameter values have been added to the program. First, the addition of a "Modem dialup Option" was added for users of the Hayes Smart- modem. You may select use of either touchtone or pulse dialing. The pro- gram is preset to touchtone and may be preset at pulse for startup. (See programming notes). Also, a parameter has been added which allows you to select the type of display, the monochrome or color video monitor. This is intended for users with both displays connected at the same time, allow- ing change from one monitor to the other during terminal operation. This does not affect which display will be used at program startup. The display used at startup is determined by the selected switches on the system board. Those of you who will not utilized the features just mentioned, need not make any changes to the program. 5) The original IBM program displayed "You are Starting up as a Terminal" when you entered the terminal operation mode from the terminal selection menu, and displayed "You are back as a Terminal" when returning from the function selection menu. Since this program modification bypasses terminal selec- tion, a feature has been added telling you what kind of terminal you are are using. For example, "Starting as a Full Duplex Terminal" or "Starting as a PC Computer Terminal". This is true for the "Back as" statement also. 6) Download/Upload capabilities have been provided for use in Full Duplex and Personal Computer operation. This section describes Download, and item 7 describes Upload. The original program for these capabilities was sup- plied by Morris Thompson, Dallas, Texas. I have made further changes and improvements. The Download capability allows you to store all incomming data on diskette. This function is selected from terminal operation by depressing F2. Selection of item 4 then allows you to designate a local file name for input of data. An option has been provided to printout a file directory of either or both disk drives before naming the input file. Also, the opened file will append the data to any existing file, rather than erasing the data if you name an existing file by mistake. Error trapping is provided during the file directory printout, and program operation to pre- vent a program stop. (A Download file is called "Log File" in the program.) A status symbol is provided on the last display line(25). When a "log file" is open, an "L" is present in the status line. If data is being recorded on the log file, then the "L" increases in intensity and flashes. When the log file is closed, the "L" disappears. More information on the status line is provided in item 8. Once a log file has been opened, it will begin recording data as soon as you return to terminal operation. Recording in the "Log File" may be sus- pended by utilizing the F10 key. The flashing "L" on the status line will stop flashing, but will be present until the log file is closed. Record- ing data on the log file resumes when the F10 key is again depressed. The status symbol "L" again intensifies and flashes, indicating that recording has resumed. (There may be a slight delay from the time a function key is depressed and when the status symbol appears on line 25.) Log files may be closed or redesignated by depressing F2, and menu item #4. A new log file may then be designated. Files which have been created by the download may be viewed after program use through functions in DOS or EDLIN. Text may not be loaded into the computer unless it is in program format, each line beginning with a number. Programs may be viewed by loading them, and then using the BASIC list com- mand. Other text may be viewed on the screen using the DOS TYPE command or copied to the printer using the DOS COPY command. EDLIN may be used to edit the received data or just to view it using the List command. Program files which have been received via download are in ASC II format. Normal storage for BASIC programs is in a compressed binary format. Pro- grams stored in ASC format take up more room on the disk and take longer to load. I suggest loading the received program and then using the BASIC "save" command without the ",a" option to store the program in binary for- mat for normal usage. 7) Upload provides the capability to transmit ASC II files stored on disk to another computer system while operating in Full Duplex or Personal Computer mode. This function is selected from terminal operation by dep- ressing F2. Selection of item 5 then allows you to designate the local file that is to be uploaded. An option has been provided to printout a file directory of either or both disk drives before naming the output file. A status symbol is provided on the last display line(25). When an Upload file is open, a "U" is displayed while in terminal operation. After making the proper entries on the Host system (the SOURCE for example) to open a MAIL, POST, or other file, F9 is used to begin file transfer. The status symbol will brighten and flash, indicating the file transfer is in pro- gress. The Upload may be suspended at any time by again depressing F9. The status symbol will again stop flashing.(A slight delay may be noticed between the time a Function Key is depress, and the resulting display on line 25.) The Upload, if left to continue, will proceed until all data has been transfered, then the "U" will disappear from the status line and a message will appear in the error message area indicating "Upload complete, File Closed". Error messages may be displayed by depressing F3. Upload files may be closed or redesignated by selecting F2, then menu item #5. Opening a new file for Upload may then be accomplished. Upload files may be text files created using EDLIN or word processing soft- ware utilizing DOS formatted diskettes. EasyWriter V1.00 files may not be transferred. Programs which have been created and stored in ASC II format may also be Uploaded. (To save a BASIC program in ASC format, utilize the "SAVE" with the ",a" option, or List ,"filename".) A word of caution must be given here. When creating text files for Upload to the SOURCE, whenever two carriage returns are present in a file without a character between them, the SOURCE computer will exit the file program and return to command level. You may avoid this by placing two spaces on blank lines, such as occur between paragraphs. (This does not occur in the mail files, since exit is accomplished with "Dot Commands".) 8) Line 25 of the display is normally reserved for soft keys and in certain applications, may be used to display special messages that do not get scrolled along with the rest of the screen. The original Async. program utilizes line 25 to display error messages on the left side of line 25, while the right side is only used under certain circumstances. For example during Personal Computer file transfer, the send or receive state is dis- played along with the current line number of the file being transferred. In half duplex mode, that area is used to designate whether in SENDING or RECEIVING state. This program utilizes the right half of line 25 to dis- play status symbols, time of day, and date, except when time and date have not been entered at program startup, or when other program functions are utilizing the area as described above. Entry of time and date at program startup requires a change to the AUTOEXEC.BAT file as well as copying the TIME.COM program from a DOS diskette to the Async. program diskette. Status symbols appear on line 25 (right half) as follows: An "H" will appear when the Hex Listing function is active. (Hex listing activated by depressing F6. The Hex listing function provides a hexadecimal value on the screen in addition to its character representation.) A "P" will appear when the Printer function is on. (F7 is the Print function On/Off switch.) A "U" will appear when an upload file is open. The "U" will brighten and flash when an Upload is in progress. An "L" will appear when a Download (or Log) file is open. The "L" will brighten and flash when a Download is in progress. Additionally, "F5=HELP" is displayed on the status line. For color televisions, or any screen utilizing a 40 character width, the status line will appear on line 25, and error messages will appear on line 24. The "*" indicating an error message is awaiting display, shall con- tinue to be displayed in the first character position of line 25. 9) Additional function keys have been utilized in this program as well as ALT H,P,and S for certain lesser used functions. F5, previously used by the Half Duplex function to "Force to SENDING state", is now utilized to dis- play a Function key help menu. This menu gives a short description of each Function, and ALT key used for special purposes. This menu is also displayed at the beginning of terminal operation. Function key F7 is used as an On/Off switch for the printer. This function was resident in the original IBM program with limited capabilities and was not documented or enabled. The program improvement allows for the printout of incoming data as well as the keyboard input. IBM had only used printout of keyboard data in the Full Duplex mode. (Use of the printer to make hardcopy of incoming data substantially slows down the data transfer. The preferred method is to use a log file and print the data at a later time.) Use of F8 will be explained in item #10. Use of F9 is explained in item #6, and use of F10 was described in item #7. Use of Function Keys 1-4 and 6 remain the same as decribed in the Async. manual. The ALT key used in conjunction with other keys also performs functions. Use of the ALT key is performed by first depressing and holding the ALT key and then depressing the associated key, then releasing both. ALT H is used to display a Telephone/LOG-ON help menu which describes use of the F8 key, while ALT P is used to "Print maximum receive buffer used" as a diagnostic aid. This is another undocumented, unpublished feature of the Async. program. IBM originally used the F8 key for this purpose but did not have this function enabled. Additionally, in the 96K version the ALT S key is used to "Force to SENDING state" for Half Duplex operation. This was an F5 function in the original IBM version. 10)This program feature is certain to be one of the highlights of the new program. Through use of the F8 key, a user may call up a telephone dial- ing menu. If a Hayes Smartmodem is used for communications, he will be able to select a telephone number associated with a service such as the SOURCE or CompuServe, etc. have the number dialed by the computer/modem and then proceed with the LOG-IN procedure by depressing the F8 key in response to each request by the Host system. Other keys are also used to facilitate the operation. For example, if it becomes necessary to re-do a particular entry, the "cursor left" (or numeric 4) key is depressed once and then the F8 key. This repeats the last entry, or backs up one entry. Depressing the "cursor left" key twice before F8 will backup two previous entries, etc. The "HOME" key is utilized to enable the F8 key at the beginning of the sequence, or from the Telephone menu. The "END" key is used to enable the F8 key for the DISCONNECT function. In otherwords, when you log off and the telephone should be hung up, simply depress "END" then F8. The screen will display "DISCONNECTING" and after a short delay, "+++" will appear followed by "ATH" and then a response from the Smartmodem of "OK". The phone will then be back on the hook! (Providing Smartmodem parameters are factory settings.) There are several variables which you must supply in the program which affect use of this function, and several different displays which appear depending upon your selections. (See programming notes for specifics.) First, if you are not using a Smartmodem, you may still use the Telephone menu and the subsequent LOG-ON procedure. In this case, the telephone menu selection does not dial the telephone but causes the correct LOG-ON to be selected. Next, you will be prompted to dial the telephone # manually and then use F8 to LOG-ON. One other option which creates a different display is the adapting of only one telephone number in the program. This eliminates the display of the selection menu and causes the one telephone number adapted to be called when you first depress the F8 key. The format of the Telephone menu is as follows: Company to be dialed, telephone #, City in which the telephone # is located, and the telephone network being used. It is recommend that you obtain several telephone numbers for each company used, at least one for each network i.e. TYMNET and TELENET, and if nothing else have the same telephone number adapted with an alternate Sign-on procedure as listed in the SOURCE manual page 2-9. A maximum of 9 numbers may be placed in the menu. The programming required for LOG-ON procedures is somewhat complicated but supports both TYMNET and TELENET procedures, as well as CompuServe network and CompuServe TYMNET entries. (See programming notes for details.) A list of telephone numbers for your area and service may be obtained as follows: The SOURCE -- type at command level >TYMTEL CompuServe -- type at command level !GO CIS-4 then menu item #8 If you have a special application, contact me for information. 11)The F2 key which is used for selection of the terminal function menu, may be depressed at any time during terminal operation. If data is being received at the time, the possibility of a "receive buffer" overflow is present. It may be necessary to exit terminal operation, for example, to select a new Upload or Download file. To eliminate the possibility of data loss, an XOFF is transmitted to the receiving computer if XON/XOFF is being supported as well as an XON which is transmitted when returning to terminal operation. XON/XOFF is supported by many computer systems in- cluding the SOURCE. This control code is the same as is what is sent to the Host computer when the CTRL S and CTRL Q are depressed to stop and start the scrolling of the screen. 12)The original IBM program allowed for error messages to be displayed at the bottom left half of the screen. First, you had to depress the F4 key to enable the messages, and then most likely, you heard continuous beeping from the machine. Error messages displayed using F3 indicated "Received Char. Parity Error." The new program modification eliminates the check for parity errors, but enables other error messages upon program startup. Normally, "No Parity" would be selected for use with the SOURCE and other like networks. However, when "No Parity" is selected as a parameter in this program, then 8 data bits are assumed. Only 7 data bits are trans- mitted, therefore, elimination of parity checking in that manner would cause incorrect characters to be displayed on the screen. 13)Error trapping routines have been added to the program to prevent a program stop in event of a printer error. Not every printer statement in the program was protected by error trapping, since there are many, and the ones most likely to be encountered have been protected, such as within t Full Duplex transmit/receive loop. 14)Item #3 under the Function Selection Menu (entered using F2 from terminal operation) allows you to exit the communications program temporarily to perform such tasks as listing the program, printing files, etc. and then return to terminal operation, function selection menu by typing CONT and "Enter". This program modification allows use of the F5 "soft key" feature to resume communications program operation. Simply depress "F5" to resume terminal operations in the function menu. 15)Two more options have been added to the function selection menu as entered from terminal operation using F2. One option allows you to exit the com- munications program permanently to the BASIC interpreter and the other allows exit to DOS (which is useful when you need to print a log file just received). These routines are different from the original "Return to BASIC" as provided by menu item #3. Both routines close files, and insure that the terminal interrupt handler no longer has control over the Communications port. This eliminates the potential problem of program hangup. Past ex- perience has demonstrated that if this is not accomplished, the system may sometimes need to be "powered down" to clear memory to eliminate a program hangup. This is more likely to happen when more than one communications adapter port is physically installed in the system unit. This program modification helps prevent this from occurring. When either of the exit routines are selected, you will first be asked if you are "sure" you want to terminate the communications program. If the answer is "N" or no then the program returns to the function selection menu. If the answer is "Y" or yes, then the communications program is terminated. If DOS has been selected, you are instructed to insert a DOS diskette and press any key when ready. 16)Several preset parameters for Full Duplex operation have been changed from the original settings. First of all, Even parity is selected instead of Mark. Secondly, Characters are displayed when echoed by the Host computer system. The first character to be deleted is the Carriage Return. The second character to be deleted is the Line feed and the third character to be deleted is Escape. All other parameters remain as originally set by IBM. (See program notes if other than the above settings are required). This completes the Functional Description of Asynchronous Communications Support Program Modifications. You should now have a basic understanding of the capabilities of the program. Further questions about the operation of particular functions should be answered after using the Tutorial section of the documentation. <* End of file *>