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Qmodem - Telecommunications Program Version 1.13 Page 1 Qmodem Operations Manual Version 1.13 The Forbin Project Inc. and John Friel III 24 December 1985 Copyright (c) The Forbin Project Inc. and John Friel III All rights to Qmodem are reserved by the Forbin Project Inc. Qmodem - Telecommunications Program Version 1.13 Page 2 Qmodem is a User Supported program. I am asking for a donation of $20.00 for its use. Those that donate will receive published announcements for future updates to Qmodem and other programs written by the Forbin Project Inc. Qmodem may be shared with other people under one condition; that there is NO CHARGE for the copy(s). A special note to Corporations: Site licensing is available by arrangement with the author. Do NOT make multiple copies for use inside your corporation until you contact The Forbin Project Inc. The Forbin Project Inc. c/o John Friel III 715 Walnut Street Cedar Falls, Iowa 50613 Qmodem - Telecommunications Program Version 1.13 Page 3 T A B L E O F C O N T E N T S Page Description .................................. 5 System Requirements .......................... 6 Starting Qmodem .............................. 7 Commands ..................................... 8 Alt-A Strip / Replace communication table 9 Alt-B Bells and Beeps toggle ............ 9 Alt-C Clear screen ...................... 9 Alt-D Dialing directory ................. 10 C) Clear entry(s) .................. 10 D) Dial an entry ................... 11 E) Revise the Prefix file .......... 12 M) Manual dial a number ............ 13 N) Next page of the directory ...... 13 P) Previous page of the directory .. 13 R) Revise an entry ................. 13 X) Exit back to Qmodem ............. 14 Alt-E Echo toggle ....................... 14 Alt-G Graphic mode toggle ............... 14 Alt-H Hang-up modem ..................... 14 Alt-I Information on Qmodem ............. 15 Alt-J Function key menu ................. 15 Alt-L Log drive ......................... 15 Alt-O Sub directory change .............. 15 Alt-P Communication parameter menu ...... 16 Alt-Q Redial last number ................ 16 Alt-R DOS shell ......................... 17 Alt-S Split screen toggle ............... 17 Alt-T Screen Dump ....................... 17 Alt-V View file ......................... 18 Alt-W Disk directory and Xmit time ...... 18 Alt-X Exit Qmodem ....................... 18 Qmodem - Telecommunications Program Version 1.13 Page 4 Alt-Y Delete a file ..................... 19 Alt-Z Xon / Xoff toggle ................. 19 PgUp Upload menu ....................... 20 PgDn Download menu ..................... 23 Up-Arrow Scroll back screen ................ 24 Appendix A QINSTALL - Qmodem Installation Program ...... 25 Appendix B TURBO Pascal Usage .......................... 26 Appendix C Dialing Directory description................ 27 Appendix D A note from the Forbin Project Inc. ......... 28 Qmodem - Telecommunications Program Version 1.13 Page 5 D E S C R I P T I O N Qmodem is a modem communications program. It can store many phone numbers in a personal directory for later recall. It will handle a variety of modems connected to the PC. Transfer files to other computers using either XON / XOFF or the ever popular XMODEM protocols. The program was written using Turbo Pascal from Borland International. Qmodem - Telecommunications Program Version 1.13 Page 6 S Y S T E M R E Q U I R E M E N T S Qmodem requires an IBM PC/XT/AT/PCjr or close compatible with 192K, a Color/Graphics or Monochrome card and monitor, and a serial port and modem. It should be noted here, that Qmodem sometimes does not work on a PC when other background software is running. I have heard a few horror stories where a screen clock routine caused all sorts of problems with the serial port. Qmodem - Telecommunications Program Version 1.13 Page 7 S T A R T I N G Q M O D E M Throughout the documentation, you may run into the characters [RETURN] and <cr>. These represent the return key on the keyboard. If you see these in the text, press the return key rather than typing in the string. Qmodem is started by entering "Qmodem [RETURN]" from the DOS prompt like the following. A>Qmodem [RETURN] Please read the opening screen carefully. Press any key to continue on into Qmodem. At the top of the next screen, Qmodem displays the version logo and what type of display card you are using. Immediately after the logo, Qmodem looks for 6 files on the disk as follows: QMODEM.CNF - the configuration file. QMODEM.KEY - the function key file. QMODEM.PRE - the dialing prefix file. QMODEM.FON - the dialing directory file. QMODEM.XLT - the strip / replace table file. QMODEM.WND - the window definition file. If you are just starting and do not have the files listed above, Qmodem will create most of them for you. Two of them: QMODEM.CNF and QMODEM.WND are created by the Qinstall program listed in Appendix A (also on you Qmodem Disk). For the dialing directory, Qmodem will initialize all of the communication parameters by asking you 3 or 4 questions. Qmodem - Telecommunications Program Version 1.13 Page 8 C O M M A N D S There are 29 commands in the Help Menu as follows. Alt-A ........ Strip / Replace screen Alt-B ........ Beeps and Bells toggle Alt-C ........ Clear screen Alt-D ........ Dialing directory Alt-E ........ Echo toggle Alt-G ........ Graphics mode toggle Alt-H ........ Hang-up modem Alt-I ........ Information on Qmodem Alt-J ........ Function key menu Alt-L ........ Log drive Alt-O ........ Sub directory change Alt-P ........ Communication parameter menu Alt-Q ........ Redial last number Alt-R ........ DOS shell Alt-S ........ Split screen toggle Alt-T ........ Screen Dump Alt-V ........ View file Alt-W ........ Disk directory and Xmit time Alt-X ........ Exit Qmodem Alt-Y ........ Delete a file Alt-Z ........ Xon / Xoff toggle Home ......... Main Menu window PgUp ......... Upload menu PgDn ......... Download menu Up-Arrow ..... Scroll back screen Ctrl-End ..... Sustained BREAK signal Shft-Tab ..... Add Linefeeds toggle Ctrl-PrtSc ... Printer echo toggle Ctrl-Home .... Capture Buffer toggle All are selected by pressing the corresponding key combinations on the keyboard. Qmodem - Telecommunications Program Version 1.13 Page 9 Alt-A Strip / Replace table. Pressing the Alt-A key combinations produces a screen containing the ASCII values 0 through 127 and their translate equivalents. Above the translate table is the Character representation of the highlighted entry, both received and translated. If, Qmodem has created the file, all entries will have duplicate translate values. This is referred to as "No translation performed". To change (translate) an ASCII value, you move the highlighted (semi box looking thing) around the table (up, down, left, and right) to the number you want to strip or replace. The number to the left of the dash is the ASCII position in the table. The number to the right of the dash is the character you will see when Qmodem receives the number on the left. To change the character from the input, press the Space Bar once. You will receive a prompt at the bottom of the screen asking for an integer between 0 and 255. To strip the character from the input, you need only replace the number on the right with a 0 (ZERO). Press [RETURN] to complete the change. The S key will swap the table showing the high bit entries 128 - 255. Repeat the procedure to change any of these also. When you are finished, press the [Esc] key to save the changes (if any) and return to Qmodem ready. Alt-B Bells and Beeps toggle Qmodem can now be made totally silent. The Bells and Beeps to signal you that something is different can be very distracting in an office environment. You can set Qmodem's default state in the installation program Qinstall, or toggle it on and off with Alt-B. Alt-C Clear screen This will clear the screen of all data. If you are in split screen mode, this will only clear the bottom portion of the screen. In addition to clearing the active screen, if ANSI graphics mode has been enabled [see Alt-G in this document], Qmodem will also send the escape sequences necessary to reset the screen colors you have selected. For those of you who call Bulletin Boards that have those neat color screens, sometimes, the colors end up different than you would like. Using Alt-C will reset the color on your screen back to your configuration selections. It should also be noted; some clone computers, like the Tandy 1000, use ANSI.SYS for the CLS command from DOS. You may see "<-[02J" when typing CLS. This means you have booted up Qmodem - Telecommunications Program Version 1.13 Page 10 without the ANSI.SYS in your CONFIG.SYS file. You need to add the following line to your CONFIG.SYS file: Device=ANSI.SYS<CR> <-- <CR> means RETURN key Make sure you have this if you want ANSI graphics or your Al-C puts funny characters on your screen. Alt-D Dialing directory. The following is an example of the dialing command prompt at on the screen. * Dial number(s) [ <cr> for Dialing Directory, <Esc> to exit ] * This is the quick entry prompt. Here, you can enter your dialing directory number(s) and skip the dialing directory. All of the dialing prefix codes are valid. For example, to dial directory number 12, you would just enter "12<cr>" and Qmodem will process the call. Instructions are given below for dialing up to 10 different numbers in a single command! With the use of the optional prefix codes, long distance services may be utilized. Some services require the prefix codes before the actual number, another needs it just at the end of the number, while still others need two codes sent out. Qmodem can handle all of the above cases with ease. Refer to the dialing prefix subcommand below for a full explanation on how to use the prefix codes. The dialing directory can hold up to 200 names, numbers and communication parameters. This command is also a small environment in itself. From here, you can dial or revise any one of the 200 numbers, change any one of the 5 prefix dialing strings, enter a manual dial mode or just page through the listing. There are Nine sub-function as follows: C) Clear entry(s) D) Dial an entry E) Revise the Prefix file N) Next page of the directory M) Manual dial a number P) Previous page of the directory R) Revise an entry X) Exit back to Qmodem #) 0 to 9, shows numbered page Clear entry(s) The familiar "Number >" shows up again waiting for you to Qmodem - Telecommunications Program Version 1.13 Page 11 enter a number in the range 1 - 200. Pressing [RETURN] exits back to the dialing option menu. After entering a number, say 1 for example, Qmodem asks "Through >". Here you can enter a larger number if you want to clear a continuous group or press [RETURN] and Qmodem will repeat the first number for you. Last, Qmodem says "Are you sure ?". To clear them a 'Y' or 'y' must be entered, anything else and Qmodem aborts the clear command. Dialing an entry Again, the option side of the screen will clear and you will see the prompt "Number >". Now you have two options: One, you can enter a number in the range 1 - 200 and press enter, or Two, you can prefix the number with one of five characters, [ +, -, !, @, and #]. This will cause one of the five optional prefix strings to be tacked on to the phone number from the entry. The following examples show both good and bad dialing entries: Good ==> Number >+1 Number >#200 Number >123 Bad ===> Number >a12 (a is not a valid prefix) Number >201 (number > 200) Number >$1 ($ is not a valid prefix) As I mentioned above, Qmodem now has the capability to dial up to 10 different numbers at one time! At either of the dialing prompts (quick dial or from within the dialing directory), you can specify up to 10 different entry numbers (complete with prefix codes) to be cycled through until a connection has been established. At the dial prompt, you are now allowed to enter up to 70 characters that define the entries in the phone book. An example will be helpful now: [(dial prompt)] +1, +12, +123, +!199- 50 51,52,53<cr> Whew! That is a lot of dialing commands! Here is what happens next. Qmodem parses (takes apart) the string of characters and places each dialing command into a separate holding area. There are only 10 such holding areas so Qmodem will ignore any extras. The characters that tell Qmodem that this is a new number are the comma "," and the space " ". Commas and spaces can be next to each other for clarity if you so choose. As in the example, the first area will contain the string "+1". The second will contain "+12", third "+123", fourth "+!199-", fifth "50", sixth has "51", seventh holds "52" and the eighth contains "53". As before, note that commas and spaces can be used together and are ignored by Qmodem. When Qmodem finds a Qmodem - Telecommunications Program Version 1.13 Page 12 holding area that has more that six characters, it flags it as invalid and goes on to the next one. Remember, the maximum characters is six for any one dial string! Now comes the neat part! If you enter two or more entries to dial, Qmodem automatically puts you in Re-Dial mode and starts through the list, one at a time until it makes a connection. When Qmodem senses the connection, it removes that entry from the list so that when you finish the call, you can press Alt-Q to continue with the previously selected numbers. Revise Prefix entries This is much the same as revising a dialing entry. A window will open up near the bottom of the screen showing you all 5 of the prefix entries. Enter the prefix character that corresponds to the string you want to change or press [RETURN]. To clear an entry, press [SPACE] and then [RETURN]. As stated earlier in the documentation, the prefix codes can be used in a variety of ways. Let me set up a couple of examples to demonstrate the versatility of prefix codes. I will make a couple of assumptions: that we are using a Hayes compatible modem and that we use three different long distance services. Here are the Prefix code strings currently stored: +) ,,,1234567 -) 1 !) 123-4567,,,1234567 @) 9,, #) 999-9999,,,1234 Let's say we are using the type of service that needs the special codes at the beginning of the call. We want to call number 12 in the directory. The correct entry to the dial subcommand would be "!12". The resulting command sent to the modem would be: ATDT999-9999,,,1234319 266 8086<cr>. The commas used in the prefix codes are assumed to be the default 2 second delay used by most Hayes compatible modems. If you use a long distance system, you will have to experiment with how many commas you need to make a successful call. In the second scenario, the service in use needs a password at the end of the long distance number. So, to dial number 12 again, use the command "12+". This will send the following string to the modem: ATDT319 266 8086,,,1234567<cr>. Qmodem - Telecommunications Program Version 1.13 Page 13 And last but not least, a service that uses both types of passwords. To make things seem worse, we are going to make the call at work using the PBX exchange. This way, I can make full use of three prefix codes at the same time. Once again, we will dial 12 from the directory. The dialing command would be "@!12+". The string sent to the modem would be as follows: ATDT9,999-9999,,,1234319 266 8086,,,,1234567 Of course, this string is 45 characters and most modems limit the input to 40. Be careful not to exceed the limit! Take out unnecessary spaces and commas to fit. Manual dial With manual dial, any combination of numbers and letters (like SmartModem(tm) commands) can be used. Note too that the dialing prefixes are valid in manual dial mode! Also, after using manual dial, the Alt-Q redial will use the number entered for the last manual dial. This will most likely save some typing time for those of you that use strange dialing combinations. I did not put a limit on the number of characters and or letters that could be entered in the manual dial. It is up to you to determine how many characters that can be entered before your modem will stop accepting data. Next page Shows the next page of the dialing directory unless page 10 is already displayed. Previous page Shows the previous page of the dialing directory unless page 1 is already displayed. Revise an entry The options side of the screen will clear and a prompt will say "Number >". Enter the number of the directory to be changed. Note that the number to be changed does not have to be displayed for this to work. Any number between 1 and 200 including 1 and 200 will work fine. A window will open up in the top middle of the screen. Each part of the entry number is displayed, one part at a time, and waits for you to enter something. If, for example, you are Qmodem - Telecommunications Program Version 1.13 Page 14 updating just the number for a bulletin board, when the name is displayed, just press [RETURN] to skip to the next entry. A null entry in the form of [RETURN] at any prompt in the revise window will NOT change the previous data for that entry. In other words, you won't have to retype all of the data every time you want to make a small change. When the revision is complete, the window will disappear and the directory will be updated on disk. Exit dialing directory This will make the dialing directory window disappear and bring back the main screen just as it was before. Alt-E Echo toggle This will turn on and off the Echo feature of Qmodem. This is used in case your keyboard strokes are echoed like "HHEELLOO" or not visible at all. Alt-F Configuration menu The configuration menu has been moved to a separate program called QINSTALL. Refer to Appendix A for instruction on Installations. Alt-G Graphics toggle This is used to toggle the display of ANSI graphics. It also controls the music to be heard if there is any. To use ANSI graphics, you MUST have the ANSI.SYS in your CONFIG.SYS file at boot-up time. For further questions about ANSI, please consult your DOS manual. Alt-H Hang up the Modem This may do one of two things depending on what you have entered in the configuration. If you have entered "DTR" for the modem hangup string, Qmodem will toggle the "DTR" signal and the connection will be dropped. Otherwise, it sends out the Modem HangUp string. Qmodem - Telecommunications Program Version 1.13 Page 15 Alt-I Information on Qmodem This will always tell you what version of Qmodem you are using, The day it was compiled, and MY name, John Friel III. If you have any problems with Qmodem, please send me a card or a letter and include this information. This is the only way I can accurately solve the problem. Alt-J Function key menu This will open up a rather large window with 5 parameters. Straight, Shifted, Ctrl, Alt and Return to Qmodem. Of course this is only good for the 10 function keys. Select 1-4 to view the current definitions for the key group. If you want to alter any of the keys, enter the number to the left of the definition at the bottom. There are Two special character you can use. The "{" character will be substituted by the [RETURN] key, and the "~" will cause a one-half second pause. Alt-L Log new drive This opens a small window and asks for the drive letter to become the default drive. This works in conjunction with the Alt-W and downloads if no alternate drive was defined. Drive letters A through Z are valid. Alt-O Change Sub-directories You MUST be using DOS 2.0 or higher for this command to work. This has to be one of the neater features of Qmodem. With this command, not one, but two windows open up. The long tall one on the left of the screen is a listing of valid sub-dirs for the current directory you are in. if you don't have any sub-dirs or don't use them, this would be blank. the other main window lists your current path (if any) and waits for you to enter a CHDIR command. Any valid CD command can be entered here, not just what shows in the left column. Examples: The current sub dir is C:\TURBO\QMODEM and I pressed Alt-O. The left column would list . .. TESTING COLOSSUS Only 2 optional sub-dirs showed up. To select TESTING, you only need enter "testing" in the main window. No need to type the whole thing in again. If you enter something wrong, Qmodem will give you the message "Invalid CHDIR command. No changes Qmodem - Telecommunications Program Version 1.13 Page 16 made." and the windows will disappear. On the other hand, Taking the same example as above, if I wanted to switch to my optional download directory, I could have typed in \COMM\DOWNLOAD to the prompt and (provided the path was valid) I would then be at my download sub-dir. Then I could do an Alt-W to check things out. Note too, that if you include the drive specifier with a new path command, only the path on that drive is changed. You will not change your current logged drive to that which was specified. This is important to remember, The only way to change the logged drive is with the Alt-L command. Alt-P Communications parameters You can change your communication parameters "on-the-fly" without having you modem hang up. Just select the right parameters from the list shown. Pressing [RETURN] alone keeps the previous setting and exits to Qmodem ready. If one of the list entries is selected, the communication parameters are altered to reflect the new choice before the window disappears. Alt-Q Redial last number The last number dialed through the Alt-D command can be repeatedly dialed until connection is made. You MUST have used the Alt-D first or you will get the message "Nothing to Redial". Provided there is a number to redial, Qmodem shows the current time redial was entered, the current retry number, the time and the statistics about the number (who and what the number is). Depending on how you have your modem set up, specifically the S7 register in the Hayes, the modem can time out and you get a "* Modem timed out or line busy *" message or the Redial delay was hit and Qmodem cycles the redial itself. Please keep the Redial delay above 45 seconds, That way you are assured of getting at least a busy signal and not cycling just as the BBS is answering the phone. While the window is open, you have Three commands: C)ycle cancels the current call in progress and goes on to the next number. D)elete cancels the current call and deletes it from the queue. This means Redial will no longer try the number. Any KEY will cancel the redial window and bring you back to Qmodem's terminal mode. Pressing Alt-Q again will restart the dialing cycle again. Qmodem - Telecommunications Program Version 1.13 Page 17 Alt-R DOS shell If there is enough memory in your system and a copy of COMMAND.COM is in the current path, you can temporarily drop to DOS and return. All DOS commands are then available, should you wish to format a disk for example. You can NOT execute any program that attaches itself to DOS. SideKick is a good example. To return to Qmodem, enter the EXIT command at the DOS prompt. Remember, not all programs can be executed in this fashion, Qmodem is not designed to be a DOS shell. Qmodem will try to position you back to where you were before execution of Alt-R. But because of stupid Drive Letter limitation in DOS, Qmodem may fail in this task. Drive letters higher than O: are not recognized as valid and return an error, even though DOS 3.0 and up allow for drives up to Z. Turbo Pascal mimics the error and will not let you log a disk with the ChDir procedure higher than O:. I have gotten around that to some extent, but it is iffy at best. Qmodem will print a "Warning" message on the screen upon return if you were logged to a drive higher than O:. If, while you were in the DOS shell, you changed drives and the logged drive previous to the Alt-R was higher than O:, Qmodem will say: * Warning: previous Drive\Path may be different. This means you should check with Alt-O and Alt-L to see where you are. Alt-S Split screen mode The screen is divided into two partitions. The bottom partition has 4 lines and the top has 20 lines. I thought there might be a need for something like this so here it is. Alt-S is a toggle, so hitting Alt-S again will drop you out of split screen mode. This is now true split screen mode complete with a 254 character buffer. Pressing the <CR> transmits the buffer. The keystrokes are kept track on on the dividing line. The character "{" can be used to substitute a [CR] in the string. Alt-T Screen Dump This copies the screen in its entirety to a file as specified in Qinstall. The screen is APPENDed to the file with a Time and Date stamp. Qmodem - Telecommunications Program Version 1.13 Page 18 2.16 Alt-V View a file This has several nice features wrapped into one. It will do a selective directory search if wildcards are used in the filename. Any number of these can occur until you either enter a valid filename or you press [RETURN] for an invalid filename. Both exit back to Qmodem ready. If you enter a valid filename, you are then asked what method you would like to view the file. Options include 1) Qmodem internal method, 2) DOS TYPE command, and 3) your favorite List or Browse utility. The last two choices depend on how much free memory you have in your machine. Refer to the DOS Shell command as the last 2 choices use a subset of the DOS Shell. If you select 3, the window clears and you are given a chance to read the bottom line which states: "Press [SPACE] to pause, [Esc] to exit. Bytes queued = X". The later part has to do with the amount of data coming in while you are viewing a file. This will let you know where you are with respect to communications. Alt-W Disk directory with Xmit time This is just like the DOS version of DIR /p. Depending on where you are with respect to sub-directories, all of the normal files are displayed with their respective attributes. One of the enhancements I have made is to add the Transmit times to each file. This Xmit time is is based on your current baud rate set by the Alt-P command. Try changing the baud rate and doing an Alt-W and see the Xmit times change. Don't you wish we all had 9600 baud modems?? I do! For those of you who have very lengthy directories, you can press the [Esc] key and Qmodem will skip the rest of the files and show you the free space on the drive. That's something DOS won't do. Alt-X Exiting Qmodem Pressing Alt-X will open yet another window (do you get the feeling that I like the use of the windows??) and ask if you really want to exit. Of course, this is just a safety valve in case that you really didn't intend to press Alt-X. If you do exit though, no matter where you are in your hard disk, Qmodem will return you to where you started. Qmodem will also close your Capture File if it is open and restore you system to normal. Another command has been added to the Alt-X, entering an 'X' in response. This will cause Qmodem to exit to DOS and leave the DTR line active. If you were online with another computer, you could issue the Alt-X command, enter an 'X', format a disk or some such thing, and re-invoke Qmodem and still be online. Qmodem - Telecommunications Program Version 1.13 Page 19 Alt-Y Delete a file Yes Virginia, there is a file delete routine in Qmodem. Like most file delete methods, Qmodem asks for a valid filename and checks to see if that file exist in the current directory. If it does, it asks you again if you really really want to delete this file. This will be the last chance before you might do something that can only be regretted later. Please be careful with this one! Alt-Z Xon / Xoff toggle This will toggle the Xon / Xoff error checking built into Qmodem. Xon / Xoff is a very simple means of flow control usually used by mini and mainframe computers. With Xon / Xoff in the OFF mode, a buffer overrun may occur in Qmodem on long ASCII transmissions. Qmodem - Telecommunications Program Version 1.13 Page 20 PgUp Upload a file The PgUp key will open a window and ask you what type of transfer protocol you would like to use. The choices are spelled right out. 1) ASCII 2) Xmodem 3) Xmodem CRC 4) Relaxed Xmodem 5) IMP 5) Exit. I personally got tired of adding '=X' to all of my file transfers with PC-Talk. How many times have you been in a hurry with an upload or a download and forgot the '=X'? Did it screw things up? Now you know why I like to put things in menus. Let me explain a about the different transfer methods. ASCII Transfer. When you select ASCII for the transfer method, be aware that line noise could make that nice looking documentation look funny on the other end. Enough said. The options that immediately show up for the transfer are as follows: 'Enter the filename to Transmit >' Answer this with the file you want to send. Next you get a list of transfer methods. 1) Prompted 2) Time delay 3) No delay. Each one has its advantages and disadvantages based upon what kind of computer you are talking to. Prompted asks you for the character to look for before sending a line of data. The prompt character cannot be a [SPACE]. Time delay asks you to enter a number in Hundredths of a second to wait before sending a line of data. No delay is a 'Blast that data' until it is all sent. When ASCII mode is selected, XON / XOFF protocol is also in effect. This was added at a very late date to support the mini and mainframe methods. At any time during the transfer, pressing the PgUp key will terminate the operation and bring you to the Qmodem ready mode. XMODEM Transfer. There are two methods currently used in public domain to compute the validity of data sent via XMODEM. The first method is called checksum. In checksum, the data block has all of the bytes added together and is then ANDed with hex 'FF'. While checksum is a pretty reliable method of insuring that the file you sent is correct, errors can creep in. I believe the rate of error detection is somewhere near 99.6%. The second method of error checking is called CRC, short for Cylindrical Redundancy Checking. This method has an error detection rate of 99.9969%. Unfortunately, not all BBS software has CRC transfer available. Check with your local Qmodem - Telecommunications Program Version 1.13 Page 21 board to find out which method should be used. Qmodem is intelligent enough to figure out which is being sent when you download, so if you select the wrong one, Qmodem will make sure you get it right. First, enter a valid filename to transmit. Qmodem will check it out. Qmodem will wait approximately 20 seconds for a NAK to be received to start the transfer. When the transfer is started, much useful information is displayed. Total blocks to send, Transmit time based on the current baud rate, The block being sent, The current error count, and the time remaining till completion. The time remaining till completion is based upon the number of blocks remaining at any given time. Lets face it, You will not be sending your data at the full baud rate all of the time with XMODEM. The time delay for the NAK/ACK response slows this down. Qmodem is fast though and this will certainly help the phone bills. Here too, pressing the PgUp will terminate the transfer if so desired. Relaxed Xmodem is nothing more than regular Xmodem, except the timing has been relaxed by a factor of 10. In other words, it takes ten times longer for the error condition to be generated. CompuServe users will appreciate this. In fact, it was because of the way CompuServe's computers handle (or fail to handle) Xmodem that this was added. Only use "Relaxed Xmodem" when talking to CompuServe and even then use it at your discretion. The last one is IMP. This was completely thought up by me and should NOT be confused with any other protocol out there. Again, this is Unique to Qmodem v1.11 and up. IMP (Internal Modem Protocol) is just that, it relies on the availability of modems to do their own data transmission checking. A good example would be the much talked about MNP from Microcom. MNP protocol can be implemented on the hardware level usually inside your modem. When two modems connect using MNP, the modems do all the checking and retransmission necessary for a clean exchange. Several modem manufacturers like ARK (ARK 24K), Novations new 2400, MultiTech's new 224 etc. have MNP built in. But how does Qmodem take advantage of the MNP? Simple, it doesn't do anything! Actually, the modems are always verifying the data so there ARE no errors in the transfer. IMP is a block oriented transfer method that uses no ACK or NAK in the Xmodem sense. Every block that goes out is guaranteed to get there the way it was sent. So, IMP does not wait for the other computer to say if the block was correct or not, that is handled by the modems in REAL time. But why does CTS have to be used? In my experiences with MNP in the modems, they use the CTS signal to temporarily halt the flow to the modem when an error Qmodem - Telecommunications Program Version 1.13 Page 22 does occur. If they didn't, Qmodem would overflow the modem and lost data would result, and ultimately, a bad file transfer. What are the advantages of IMP? In my testing (from Virginia to Iowa, using 2 ARK 24K modems), IMP showed an impressive 115 blocks a minute at 2400 baud. To put that in perspective, normal Xmodem (or Xmodem CRC) could only get about 88 blocks a minute at 2400 baud. Remember, to use IMP, the modems MUST have an internal protocol. Qmodem - Telecommunications Program Version 1.13 Page 23 PgDn Download a file Here too, you get the menu asking for the type of transfer you want to use. Enter the appropriate response. Let me jump right into the separate protocols. ASCII. The screen will clear and you will be told that pressing the PgDn key will terminate the transfer and save the file. If you start the transfer, but no data has been received, Qmodem will pretend as if no file was ever sent. I don't think ASCII need much more explanation. XMODEM. This is the new and improved method of keeping track of the transfer. All types of errors are kept track of. When the transfer starts, the download window clears and a list of all of the errors are displayed. Total blocks received is displayed at the top. The last line of the window shows the most recent error message and at which block it occurred. If you receive ten errors in a row, Qmodem will cancel the transfer. As soon as one block of data is received successfully, the error count is set to zero. Qmodem tries to recover from all data errors. You will note too the speed of which Qmodem can recover. If you are having a problem, give me a call. I am willing to talk to you about any transfer problem that you may encounter. Again, "Relaxed Xmodem" was designed for talking to CompuServe. See the description under File Upload in the previous section. For a description of IMP, see the previous discussion under Upload protocols. Now a brief description of the errors that can be detected during an Xmodem transfer. Qmodem keeps track of each type separately. 1) Long block error - Caused usually by line noise and this creates extra characters in the transmission. 2) Short block error - if the line is weak or you are recovering from a previous error, this can result. It means that Qmodem did not receive enough characters to complete the data block. 3) SOH error - The first character of every Xmodem block is the SOH character (01 HEX). If the first character is not an SOH, Qmodem flags the block as bad. Chances are that if the first byte is bad, so are a few others due to the fact that line noise usually last long enough to corrupt more that one byte. 4) Complement error - The data block had two bytes in the header to hold the block number that is Qmodem - Telecommunications Program Version 1.13 Page 24 being transmitted/received. The second of these two is the complement of the first (first byte XOR 255). This ensures that Qmodem is getting the correct block. 5) Block # error - This is usually caused by line noise too. The transmitting computer received a NAK in place of the ACK Qmodem sent and resends the block you just received successfully. Essentially, Qmodem ignores the block and sends another ACK. 6) Checksum/CRC error - Every block of data in Xmodem is followed by either a Checksum byte or by 2 CRC bytes. CRC is a more accurate method of error detection, but requires one more byte to be sent in every block. If the Checksum or CRC is wrong, Qmodem sends a NAK and discards the data. Again, line noise is usually the culprit. This might be an appropriate place to mention that if you have "Call Waiting" with your phone service and someone calls you while you are doing an Upload/Download, you stand a chance of getting errors. This may even terminate the transfer depending on the noise generated. Be forewarned! Up Arrow Scroll back the screen By pressing the Up arrow, you can scroll back through the previous lines of data that have come to the tube. The valid keys in scroll back mode are 1) Up arrow - go up one line 2) Down arrow - go down one line 3) PgUp - go up one page 4) PgDn - go down one page 5) Esc - exit scroll back Pressing the [Esc] will exit scroll back mode. This should be pretty much self explanatory. When you reach the top of the scroll, you get a message : * Top of Scroll When you are at the bottom : * Bottom of Scroll Qmodem - Telecommunications Program Version 1.13 Page 25 A P P E N D I X A Qinstall - Qmodem Installation Program Qinstall takes the place of the Alt-F key combination that previous versions of Qmodem had. More information was needed to explain the configuration than Qmodem could hold. I have taken the Alt-F screens and reworked for ease of setup. Qinstall will read any QMODEM.CNF file starting with Qmodem version 1.06. You may see garbage in some of the data entry areas depending on how old your CNF file is. It is important to note; Qmodem v1.13 REQUIRES running Qinstall v1.13! Lets jump right in and execute Qinstall. The first thing you will see is the familiar QMODEM logo and a list of options. These options are basically the same ones that Qmodem used to have. I recommend going through all Six so you can make sure the data looks good. Select option number One. Qinstall will display the Six Color Options of Qmodem, a Color Chart, and the sample Qmodem display near the top. Depending on the type of monitor card you are using, the edit fields are either inverse video (for Monochrome) or hi intensity White on Blue (for Color Graphics). Several keys need to be explained; as Qinstall contains a mini editor. Tab, Shift-Tab Goes from field to field. Up and Down Arrows Same. Left and Right Arrows Moves by character. Insert and ^V Toggles INSERT mode. Delete Deletes 1 character. Esc Exit with no update F10 Exit and Update. F1 Context sensitive Help If you have any questions on any of the fields, press the F1 key and Qinstall will show you more information about that field. If you do not want to keep the changes made, and would like to reset them to whatever they were when you entered the screen, press Esc. To tell Qinstall to keep the changes you have made, press F10. Pressing F10 does Two things... a preliminary Edit on the data, and if it is good, saves it. If you have any wrong data, Qinstall will warn you and position the cursor to the offending spot. Qinstall has been created with the NEW USER in mind. If you are having trouble, I would like to know about it. Please write me at the address given in Appendix D. Qmodem - Telecommunications Program Version 1.13 Page 26 A P P E N D I X B TURBO Pascal Usage TURBO Pascal was used to create Qmodem for several reasons. The language is easy to work with. It allows structured top-down programming and the ability to define your own types of variables. Just as a side note, Qmodem does not have a single GOTO statement! Another advantage is the creation of .COM files from the compiler. No more having to load BASIC and then run your program. The program editor is another big plus to the system. It emulates the WordStar editor almost completely. TURBO Pascal also lets you use all of the available memory in your system. Programs can be larger than the available memory by the efficient use of overlays. I could go on and on about TURBO Pascal. By the way, I am not affiliated with Borland International, just a very happy customer. Qmodem - Telecommunications Program Version 1.13 Page 27 A P P E N D I X C File structure of the phone directory The following is a copy from the source code which shows the file structure. Type check_bit = (even, none, oddd); phone_type = record name : string[25]; number : string[14]; speed, dbits, sbits : integer; parity : check_bit; end; Qmodem - Telecommunications Program Version 1.13 Page 28 A P P E N D I X D Please consider the donation of $20.00. Good software at a good price is hard to come by. We at the Forbin Project Inc. support the idea of "Shareware" and "Freeware" and hope all of you do too. It's because of you that I am able to bring you helpful programs like Qmodem. Thanks again. The Forbin Project Inc. c/o John Friel III 715 Walnut Street Cedar Falls, Iowa 50613