IMP (NOTES ON HOW TO USE) Copyright 1985 Irvin M. Hoff W6FFC 01 OCT 1985 INTRODUCTION: ------------ NOTE: THIS PROGRAM SUPPORTS ANY 1200 OR 2400 BPS MODEM INTENDED FOR AUTO- DIALING WITH THE "AT" PROTOCOL OR THE RACAL-VADIC PROTOCOL. IT ALSO SUPPORTS THE PROMETHEUS PROMODEM EXTENDED-"AT" 1200 BPS PROTOCOL. NOTE: IMP v241 adds KMD-type batch protocol in addi- tion to the MODEM7 type. It comes up in KMD batch. Use the command TBM to toggle batch mode to MODEM7 type if needed. RCPM systems with KMD/BYE500 support the KMD-type batch mode. The IMP modem program enables a computer to communicate with another computer. This is normally done by using standard telephone lines but with special audio tones sending serial data. Three common speeds are used, depending on the facilities available -- 300, 1200 or 2400 bps. ('bps' stands for bits per second. One character is 10 bits per second, normally. It may be 11 bits if two stop pulses are used.) WHAT IS A MODEM? --------------- A "modem" is used which provides these audio tones. This is an acronym for "modulator and demodulator". The one section (modulator) provides the audio tones for sending over the telephone line and the other section (demodulator) then converts those audio tones back to dig- ital pulses the computer uses to receive the incoming data. The modem itself is a hardware utility, usually costing around $75 to $200 for a typical 300 Baud device and from $200 to $450 for a system offering 1200 Baud as well as 300 Baud. The newest modems add 2400 bps and currently can be obtained from $435 to "way on up". (The so-called "list prices" are rarely paid even with single-unit purchases.) Some modems are intended for plugging directly into the computer while a vast majority are external devices that connect to the computer through a serial I/O connector. These are often designed to sit under the phone itself to minimize space required. An external modem has sev- eral advantages as most have numerous indicator lamps telling the user what is happening. This also makes it far more simple to use the modem on any of several computers the user may have. AUTO-STEPDOWN, A NEW MODEM FEATURE -------------------------------- The newer 300/1200/2400 bps intelligent modems have the ability to determine the maximum speed (baudrate) at which the system they are calling can use. They adjust themselves accordingly, without operator intervention or knowledge. They send a "result code" back to the local computer telling it what speed they now have. This information can be used to automatically set the local computer to the same speed. A mes- sage is displayed telling the operator what speed he has. If the operator has a reason for using less than the maximum speed to which another system might respond, he can initially restrict the modem from attempting to connect at a faster speed. Example, Compu- serve has modems that will answer at either 1200 or 300 bps. If reading and answering messages "on line in real time" many callers prefer to use 300 baud (they cannot type even that fast) rather than 1200 bps which is nearly twice the cost. IMP takes advantage of this automatic stepdown feature. It has the modem attempt to connect at 2400 bps. If that is unavailable at the answering end, the modem tries for 1200 bps. When connected, IMP shows the speed currently in use and automatically adjusts the local I/O to match. (IMP is the first and currently the only free modem program to take advantage of this new modem feature.) The operator can easily select the "SET" command should he wish to override the automatic "start trying at 2400" and have a specific speed dialed (such as 300 baud for Compuserve for hand typing messages at lower cost, etc.) The automatic feature is reinstated by either using the "SET" command for 2400, or merely calling up the modem program from the disk once more. Note: The US Robotics Courier auto-steps from 2400 to 1200 but not to 300, as do most of the other new modems with 2400 bps. PURPOSE ------- The program discussed in this guide allows each computer involved to directly control its own modem, converting DC pulses into audio tones which are sent to (or received from) the telephone line. (The standard 1200 baud transmissions use "DPSK" (dibit phase shift keying) instead of "AFSK" (audio frequency shift keying). For short distances, no modems are required as the computer can provide the necessary digital voltages. This discussion is centered around systems intended for use over distances ranging from several miles to literally around the world. FEATURES: -------- A program to communicate with another computer can range from very simple to very complex. Although IMP has a number of quite useful fea- tures (some of which other modem programs do not currently offer) it is one of the easier programs to learn and use. A list of some of the features offered by this particular program include: 1) Ability to talk with another computer via keyboard at each end. (Called the "terminal mode".) 2) Ability to operate a remote mainframe computer such as TYM-SHAR, or special data bank systems now commonplace. This includes "bulletin board" systems for receiving, sending or just read- ing messges or other types of information. 3) Ability to upload (send) or download (receive) programs from other computers whether TYM-SHAR, data banks, remote hobby systems or just another individual in another location. 4) Ability to automatically transfer a group of files (called "batch mode". Two popular methods included, KMD batch mode and the older MODEM7 batch mode. 5) Ability to copy incoming information on a printer. If the print- er is too slow to copy the data directly, the extra characters back into a large storage buffer until they can be printed. 6) Ability to copy incoming data into memory for automatic transfer to a disk file. 7) Accomodates any computer clock speed up to 25.5 MHz. in 0.1 Mhz. increments for uniform results. (The clock speed is actually of modest interest, it is only used for setting timing loops.) 8) Advanced type of error detection (CRC or Cyclic Redundancy Check) using automatically generated high-speed lookup tables. 9) Ability to send any of 10 different pre-programmed function keys. (These keys are very easy to reset, using either of two exter- programs provided.) 10) Automatic disconnect from the telephone line when using CTL-N, "D" or "Z" as an option during file transfer. 11) Automatic or manual 1k protocol for increased throughput and effi- ciency over the 128 character blocks long associated with such programs. 12) Supports 1200 or 2400 bps modems using the Racal-Vadic or 'AT' protocol developed by Hayes. These features basically include automatic dialing and redialing until the system being called finally answers. a) Automatic selection of a particular phone number from a library of names and numbers. (These phone numbers can be very easily changed by using either of two ex- ternal programs that are provided.) b) Automatic dialing for alternate long-distance systems (where auto-dialing touch-tone modems are used). c) Entry of a hand-typed number. Although it might be as simple to manually dial the number as hand-type it, it can then be automatically redialed indefinitely. d) Auto-linking of 1-32 different numbers for continuous dialing until one of the group is available. e) Choice of beeping continuously when connected to get the operator's attention, or beep one time and go to terminal mode immediately to catch UNIX or IBM signon messages that assume you can copy when connected. f) Automatically adjusts the terminal speed to that of system answering the phone. USING THE PROGRAM THE FIRST TIME: -------------------------------- For now, we shall assume the program is ready to use on your equip- ment. (Normally the user must make some modest changes to the program before it can be used. This includes changing the port numbers and some other personal options. These will be covered later in the section that describes how to adapt it to your equipment.) When the program is brought up is shows this display (if using the PMMI modem): IMP v240 modem pgm (type M for Menu) Copyright (c) 1985 Irvin M. Hoff Version for Datapoint 1560 modem port 28H Modem speed is: 2400 bps B>>COMMAND: x (Your version would have a different line 3 once the ap- propriate overlay was added and the baudrate might show show 1200 if you do not have 2400 available.) The cursor stops at point "x:" waiting for some sort of command. Typing a "M" followed immediately by a RETURN, shows the first page of a 3-page help guide. Several commands are similar to those already used for CP/M, such as 'ERA', 'DIR' and the ability to change disk drives and user areas. This adds tremendous flexibility while remaining in the modem command mode. To change disk drives, just say: B>>COMMAND: A: and you are in the same user area on the A: drive. You can also say: A>>COMMAND: A12: to change user areas. When finished (using this example), say: A12>>COMMAND: CPM or A12>>COMMAND: BYE and you will go back to CP/M with the original drive and user area. OPTIONS: ------- There are 6 primary options and 9 secondary options that may be typed on the command line. In addition there are over numerous commands ranging from single character to three characters that can be used (such as DIR, ERA, LOG, etc.) Those are listed on the menu. Primary Options: E, L, M, R, S, T E = Echo mode (special type of full duplex) L = Local modem (no remote echo, half duplex) M = Menu display showing features that are available R = Receive a file from remote facility S = Send a file to a remote facility T = Terminal mode (full duplex, echo provived remotely) Secondary Options: A, B, D, J, O, Q, R, S, V, X, Z B = Batch mode -- allows automatic multiple file transfer (This has been normally only used from modem-to-modem as few RCP/M systems have had batch capability. This is now changing with the introduction of KMD v04 and BYE501. Batch mode allows the use of wildcards to simplify typing numerous file names.) D = Disconnect when done, stay in IMP K = Manually initiates 1k protocol in send mode Q = Quiet mode, special purpose feature rarely used except if operating through a "BYE" program. R = Receive remote file (8-bit binary) S = Send file to remote system (8-bit binary) V = Visual inspection of an ASCII file being transferred. Not often used as most ASCII files are now "squeezed" for minimum transfer time and disk space. X = Inhibits automatic 1k request, transfers 128 char. blocks Z = Exit to CP/M when finished, disconnect from phone line Although you can get the following information from the help guide in IMP itself, showing it here will allow us to discuss the various fea- tures in somewhat better detail. - - - - - - - - - - - - - - - - - - THE HELP GUIDE, PAGE 1: ---------------------- Single Letter Commands ? - Display current settings ESC - Function key intercept character, then (0-9) M - Display the menu E - Terminal mode with echo L - Terminal mode with local echo T - Terminal mode ^Z - Clears screen (command mode only) R - Receive an 8-bit binary CP/M file S - Send an 8-bit binary CP/M file COMMAND: R (or S) FILENAME.TYP R and S can use the following subcommands: B - Batch transfer, can use wildcards (e.g., *.*) D - Disconnect when done, return to command mode K - Manual request for 1k transmissions Q - Quiet mode (no messages to console) V - View ASCII files on CRT during a file transfer X - Inhibits auto 1k request to sender Z - When done, disconnect, go to CP/M For copying text to disk use T (E or L) FILENAME.TYP [more] The single letter commands may also be used on the command line when the program is initially executed. - - - - - - - - - - - - - - - - - - DISCUSSION OF HELP GUIDE PAGE 1: ------------------------------- There are basically three types of commands that may be used with this program: 1) Single-letter commands shown on page one. 2) Three-letter commands shown on page 2, and 3) Control- commands shown on page 3. Going down the list: ? - shows current parameters. As these are closely tied in with some of the other options, we shall show a typical example later in this discussion. ESC - shows the function key intercept character. This may be easily changed using an external program called I2FUNC.COM. NOTE: typing ESC while in the command mode will display all the programmable function key definitions with the exception of the log-on string which uses CTL-L. M - shows the menu a page at a time. You may abort after any page is shown with a CTL-C E - terminal mode with echo. When talking with another terminal also also using IMP (or a comparable program), one of you must send an 'echo' back so you can both see what the other person is typing. This is needed for full-duplex operation. Usually the person originating the call will type "E" instead of "T". However either may do this. If "both" use the echo mode, the program usually starts typing a string of feedback characters since both computers are re-sending the same character over and over. You can stop this by just returning to command mode (type control-E) and then retyping "T" rather than "E". L - terminal mode with local echo. Shows what you are typing but does not send an echo of the other person's typing back to him. Can be used at both ends, in place of one person using "E". Both "E" and "L" are useful at times for some types of modems that do not use full-duplex, or for some main frame units that run half-duplex. The combination of "T", "E" and "L" gives an excellent choice to use on various systems. Normally the "T" mode is sufficient except when talking with another person and then the "E" mode at one end or "L" mode at both ends will provide normal results. If the remote system does not supply a LF after a CR, you can get that from the 'TLF' command. T - puts the program directly into "terminal mode", allowing it to send from the keyboard to the other computer, and to copy any- thing coming from the other computer with the exception of file transfers (use "R" to receive those). R - used only for receiving files from the other computer. These are usually sent in binary form with either checksum verification or more commonly, CRC (Cyclic Redundancy Checking). If ready to receive another file, you have several choices, depending on the program used by the other computer. After notifying him you are ready (or will be very shortly), you can type: B>>COMMAND: R HELLO.DOC and when he starts to send, you will receive the program which then goes directly to the disk. You could also have said: B>>COMMAND: RB This is called the "Batch mode" and is an extremely useful way to receive programs automatically, from another computer using a similar program. He will use the batch mode for sending the programs and that automatically provides the file names at the receiving end. In this manner, large numbers of programs can be transferred completely automatically, including full disks. (Assuming you care to pay the toll calls for the time it will take!) NOTE: The ideal way to receive batch mode would be: B>>COMMAND: RB (also just R is enough) since you may not know in advance how many programs he will be sending. NOTE: While receiving a file, any errors will be shown on the console CRT, indicating that portion of the program is being repeated. If the file finishes transferring normally, it will have been received error-free. Those error notices are merely to let the user know a momentary problem caused a resend. The error messages indicate phone line quality. S - used only to send programs. Similar to "R" but sends instead of receives. If the other system is ready to receive, you could then type: B>>COMMAND: S HELLO.DOC It will tell you how many records are involved and how many minutes and seconds it will take to send the program. If the other system is ready to receive, it starts the transfer, showing how many records have been sent. If any errors occur during transmission, it shows what they are and counts them. It will resend any records not correctly received at the other computer. If too many consecutive errors occur (normally set at 10), the transfer is terminated. The 'batch mode' may also be used for sending: B>>COMMAND: SB HELLO.* (sending batch mode) will send all files starting with HELLO, or can send just one file, or can send several non-related files in this manner: B>>COMMAND: SB HELLO.DOC XDIR.COM TERM.* etc. Be sure to put a space between the various files. You can include the 'Z' option: B>>COMMAND: SBZ HELLO.* IMP740.LBR I2LIB.COM When the file transfer is completed it disconnects from the phone line and reverts to CP/M. This allows you to be absent when the file is finished, offering an advantage when sending lengthy files. - - - - - - - - - - - - - - - - - - THE HELP GUIDE, PAGE 2: ---------------------- Three Letter Commands BYE - Disconnect, then return to CP/M CAL - Dial number CPM - Exit from this program to CP/M DIR - List directory and space free (may specify drive) DSC - Disconnect from the phone line ERA - Erase file (may specify drive) LOG - Change default drive/user no. (specify drive/user) and reset disks. e.g. LOG A0: or LOG B: (user # unchanged) SET - Set modem baud rate SPD - Set file output speed in terminal mode TBM - Toggle MODEM7/KMD batch mode selection TCC - Toggle CRC/Checksum mode on receive TLF - Toggle LF after CR in "L" or "T" mode for a disk file TRB - Toggle rubout to backspace conversion The following are terminal text buffer commands: DEL - Delete memory buffer and file WRT - Write memory buffer to disk file [more] - - - - - - - - - - - - - - - - - - DISCUSSION OF HELP GUIDE, PAGE 2: -------------------------------- BYE - Disconnects the modem from the phone line, closes any file that may be open and returns to CP/M. CAL - Displays the telephone library. NOTE: Use the phone number overlay to easily change the numbers that are stored. This overlay also accesses up to two alternate long distance dialing systems for the touch- tone auto-dialing modems. You can also use an external program called I2LIB to rapidly change any phone numbers. CPM - This returns to normal CP/M use, abandoning IMP. CAUTION: It does not disconnect the modem from the phone line, which allows intentional return to CP/M temporarily. DIR - Enables the user to see the library of any disk without needing to return to CP/M first. Can be adjusted when installing the program to show 3, 4, or 5 groups depending on the width of your CRT display. Normally set to 5 for 80-column displays. Shows the amount of disk spacing remaining on the logged-in default drive. (You must log in any drive you wish to write on, or to see the correct free disk space remaining.) See the LOG feature below. DSC - Disconnects the modem from the phone line whenever selected. ERA - Enables the user to erase any files from any disk without the need to return to CP/M first. Wild cards (* and ?) accepted. LOG - When a new disk is inserted, you can see the directory and read files from it but cannot write to it without getting a "BDOS ERR". This command allows you to log in a new disk so you can immediately write on it without first returning to CP/M for a warm boot. You can select drive and user number. (This also enables DIR to show the correct free disk space remaining.) You can say: LOG for same drive, user area, new disk LOG A LOG A: LOG A14 (user areas are 0-15) LOG A11: SET - Allows the user to change baudrates when desired. If using a 2400 bps modem with automatic stepdown, this would rarely be used. SPD - Sets the delay between characters and/or delay between lines in the "T" mode when using ESC F upload a pre-typed file. Since most bulletin boards and TYM-SHAR systems normally use line editors that require a delay after they have received a line, you can add delay between characters (in increments of 4 ms.) and/or enter delay between lines (in increments of 100 ms.) This is preset for most systems at 2 and 200 ms. They can be changed at any time. Current values can be checked by using the " ? " command. TBM - Toggle batch mode from KMD (default) to MODEM7. The primary difference is the way the file name is sent. The older MODEM7 method sends each character separately, expecting the other computer to echo each character. Checksum is used to verify the file name. The KMD method sends a special 128 byte block with the file name and the length of the file. This is not only far better for use with mainframe and networking systems, but also informs the operator receiving the file how long it will be. (The KMD method then automatically goes to 1k mode.) TCC - Most modem programs originally used simple checksum verification of received sectors. Most now use Cyclic Redundancy Checking which finds certain transmission errors the simple checksum system might overlook. This toggle allows the user to select checksum for those systems known to not offer CRC. When set normally to CRC, the program automatically switches to check- sum after trying several times to use CRC. TLF - If sending a file while in terminal mode (via CTL-T option) most mainframe computers will not want you to send a line feed. As all editors include the LF after CR, you have the option with this toggle of sending or not sending a line feed. If typing manually in the "T" mode, you can get a line feed with CTL-J. It is automatically included after CR with "L" or "E" modes. TRB - Allows the rubout char. to be changed to backspace if desired. DEL - If copying incoming information into memory, and you decide you do not want to bother saving it to disk after all, this closes (and then deletes) the disk file you had opened. WRT - saves what you have been copying to the disk file already opened for that purpose. When returning from the "T" mode to command mode, a warning is shown that you may lose what has been saved unless you use WRT (write to disk). NOTE: An open file is automatically written to disk should you use BYE or CPM commands to leave the program, thus preventing accidental loss of data intended to be saved. - - - - - - - - - - - - - - - - - - THE HELP GUIDE, PAGE 3: ---------------------- Local Commands while in Terminal Mode ESC E - Exit to command mode ESC F - Send file to remote system ESC L - Send log-on message ESC N - Disconnect from the phone line ESC P - Toggle printer on (or off) ESC Z - Clears screen, terminal mode ESC R - Stop copy into buffer ESC Y - Start copy into buffer Start & Stop may be toggled as often as desired. A ";" at start of line indicates buffer is copying. X-off automatically used to stop input when writing full buffer to disk, X-on sent to resume. >>COMMAND: - - - - - - - - - - - - - - - - - - DISCUSSION OF HELP GUIDE, PAGE 3: -------------------------------- ESC E - Returns to command modem from "T", "L", "E" modes. ESC F - Sends an ASCII file to the remote terminal, X-on and X-off automatically used. Optional delays available. ESC L - Will send the log-on message if one has been included in the LOGON area of the overlay. ESC N - Disconnect the modem from the phone line. (You can easily change this to whatever you like in the overlay you use for your equipment.) ESC P - Toggles the printer on-off. Very useful feature. Similar to normal control-P but in this case if the modem is running faster than normal printer speed, the characters just back into a special buffer while the printer tries to catch up. Especially beneficial when using 2400 bps as few printers can keep up at that speed. Can be toggled at any time you are in the "T", "L" or "E" modes. Often used to copy items from bulletin boards, etc. that are not worth permanently saving on disk. ESC Z - Clears the screen in terminal mode. (CTL-Z normally used but that goes on out the terminal to the remote system.) ESC Y - Used only in terminal mode. If ESC R is used to temporarily stop copying incoming text to memory, ESC Y restarts this feature. When copying to memory, a ';' appears in the first column of each line. NOTE: To open a file use: COMMAND: T FILENAME.EXT and then ESC R and ESC Y will control what is copied for saving to disk. ESC R - Stops the copy into memory, shuts off the ";" at start of each line. These two commands (ESC Y to start, and ESC R to stop) control what is being saved. When returning to command (via ESC E), you will then be warned to save the information to disk via the WRT command or it will likely be lost. (You may never use ESC R or ESC Y and just use your editor on that file later to discard unwated magerial. - - - - - - - - - - - - - - - - - - AUTO-DIALING AND AUTO-REDIALING: ---------------------------------------------------------------- There are several ways to auto-dial. 1) from the command line 2) from the phone number library line In addition you can auto-redial from either of these lines. Once the number has auto-dialed and there is no answer, it will ask you if you want it to continuously auto-redial until it does receive an answer (or you decide to abort). To get the phone library, type CAL on the command line. You then normally just type the appropriate character at the start of the line. It will show the number being dialed. You can also do this from the main command line if you know in advance what character is used for that particular number: B>>COMMAND: CAL P This calls up the "P" line in the library and dials that number, then if busy asks if you want it to continue redialing. You can use: B>>COMMAND: CAL 313-749-6569 and it will dial the number specified. You can then do either of these on the library command line, as well. This gives a tremendous versatility. NOTE: To access the alternate long distance dialing systems (up to two are offered), use the phone number overlay and fill in the in- formation regarding your access number, billing number, etc. It will then show how to enter a special character ahead of each phone number where alternate long distance system is desired. This only works where touch-tone systems are in use. - - - - - - - - - - - - - - - - - - AUTO-LINKING PHONE NUMBERS: -------------------------- If the number you want to dial is busy, you would like to have it automatically redialed until it answers. However, you might like to call any of a group of numbers and be happy to take whichever one first becomes available. Auto-linking allows a group of numbers to be listed and they are then continuously dialed one after the other, until one is available. IMP permits from 1-32 numbers to be linked together in any manner. There are two options: B>>COMMAND: CAL A,D,R,3,Z 1) B>>COMMAND: CAL F, 2) B>>COMMAND: CAL A/D/R/3/Z 3) B>>COMMAND: CAL F/ 4) B>>COMMAND: CAL A,D,A,R,A,3,A,Z 5) B>>COMMAND: CAL F 6) 1) using a comma (,) will beep continuously when connected to the first available number - touching any key stops the beep and goes to terminal mode. 2) just the one number is linked to itself and redials until connected. Beeps continuously until stopped with any key. 3) using a slash (/) will beep only once when connected and then automatically go directly to terminal mode - this is useful where some mainframes such as IBM and UNIX send a logon note assuming you are already able to copy as soon as connected. 4) just the one number is linked to itself and redials until connected. Beeps only once and goes to terminal mode. 5) illustrates how one number can be given top priority. 6) system used previously - if connected on first try, beeps one time and jumps directly to terminal mode. If no connection, asks the operator if he wants to try again or try continuous- ly until a connected is made - at which time it beeps until a key is depressed. - - - - - - - - - - - - - - - - - - CASCADING COMMANDS: ------------------ Several commands may be used on the same line. Ones normally used are: B, D, E, K, L, Q, R, S, T, V, X and Z The commands have been listed previously but will be listed here again: B) batch mode (must be used at both ends if used at all) (usually only available modem-to-modem with operators present at each end.) D) disconnets the phone, returns to CP/M after a file transfer E) echo mode for conversing with a system not offering echo. K) used to manually request 1k transmissions on systems not having automatic 1k transmissions. L) local echo shows what you are sending if no remote echo. Q) quiet mode, suppresses messages on local console. R) receive file transfers (8-bit binary) S) send file transfers, also shows transfer time. T) terminal mode - operates computer at other end like a remote terminal. Also stands for "text mode". When in "T" mode you can copy incoming to printer or to disk, and send pre- typed ASCII text files via CTL-T. V) visual -- lets you see incoming ASCII files while being sent to the disk system. X) inhibits automatic request for 1k transmissions Z) disconnects the phone, returns to command mode after a file tranfer. NOTE: The Baud rate is only used for the PMMI S-100 modem. Many of the custom overlays allow use of the SET command to change Baud rate with non-PMMI modems. - - - - - - - - - - - - - - - - - - TYPICAL PARAMETERS SHOWN BY THE "?" COMMAND: ------------------------------------------- B>>COMMAND: ? Mode: CRC KMD batch mode Rub is backspace Printer buffer is OFF Modem speed is: 1200 bps Terminal mode file buffer is inactive Unused portion of buffer is 16384 bytes Use ESC before local command in terminal mode XOFF testing used in terminal mode file output LF NOT sent after CR in "L" or "T" for a disk file Char. delay (terminal file mode) is: 2 ms. per character Line delay (terminal file mode) is: 200 ms. per character - - - - - - - - - - - - - - - - - - DISCUSSION OF TYPICAL PARMETERS SHOWN BY THE "?" COMMAND: -------------------------------------------------------- By this time, most of these parameters are self-explanatory. They primarily show how the options and toggles have been set. The user can check on any of the major parameters at any time by: 1) Typing ESC E to return to command mode and 2) Typing ? to see the list of current parameters. - - - - - - - - - - - - - - - - - - FUNCTION KEYS: ------------- There are 10 function keys which may be easily programmed with an external file called I2FUNC.COM in just a few moments. It makes the changes directly to the IMP.COM file. (There is an additional ESC L log-on selection that is programmable in your overlay.) To view the contents of the function keys, type 'M' for menu while on the command line and it will show the character currently used for the function key intercept. (It will be ESC unless you select another.) You could then type that character (followed by ) on the command line and it will display the entire contents of the function keys. - - - - - - - - - - - - - - - - - - CHANGING THE PHONE NUMBER LIBRARY: --------------------------------- The phone numbers in the library may be easily changed using an external file called I2LIB.COM. This permits any of the 36 phone num- bers to be changed in only a few seconds. It works directly on the IMP.COM file. If extensive changes are to be made, you may prefer to use an overlay file called I2NM-1.ASM. This permits using your editor to make quick and selective changes, or to substitute an entire new library. (You may need to add or remove things like '1-' for long distance dialing in your area.) That file also is used to set the alternate long-distance dialing routines for SPRINT, MCI, TYMNET, etc. - - - - - - - - - - - - - - - - - - RETRY OPTION: ------------ The consecutive error limit has been set to 10. When transferring files, if this limit is reached, the file transfer will be aborted. - - - - - - - - - - - - - - - - - - INSTALLING THE PROGRAM: ---------------------- Although this is obviously the very first thing that needs to be done, it was saved until last for several reasons. The most important of these was the need to first explain what some of the options will do when selected. By this time the user should have a fairly good idea what options would work best for him. When looking at the beginning of the program where the these are selected, it should now be rather easy to pick the ones that are most useful. There are various ways to change the program to suit a specific user. You are offered several methods. The "easy way" is to get the IMP.COM file plus the appropriate overlay for your computer. You then edit the overlay (if needed) to suit your local needs, assemble it to get a .HEX file then use the simple instruction and DDT.COM to combine the standard IMP.COM file with your overlay. The front end of each overlay contains all the information in the front of the IMP program. Generally no changes need to be made in specific overlays unless you have some particular requirement different from others using the same equipment. (Such as the log-on message, for example.) You can also use DDT to change specific bytes without editing and assembling. NOTE: Although designed with special emphasis on the auto-dialing and redialing capability of 1200 or 2400 bps modems using the Racal- Vadic or 'AT' protocol developed by Hayes, the program may be used with other modems where the operator manually dials the number, then changes to terminal mode after connecting his modem. OUR THANKS TO: ------------- A great number of people have been beta-testing this program and offering suggestions. In particular I wish to thank Wayne Masters, Roy Robinson and Tom Brady. We hope this verstile program will give you hours of enjoyment and fulfill your modem needs. It is particularly useful with the 2400 bps modems that have automatic stepdown. - Irv Hoff W6FFC