********************************************************************** Traveling Software, Inc. 18702 North Creek Parkway Bothell, Washington 98011 (206) 483-8088 ********************************************************************** The Latest About the LapLink III Device Driver Version 3.00a ********************************************************************** * Be sure to mail in your registration card to ensure that * * you will be notified of future releases of LapLink, and to * * enter your name for our monthly drawing for free software * * and hardware products. * ********************************************************************** Welcome to LapLink III. The following notes include the latest news about this version of the LapLink Device Driver. These notes add to or expand on information in the Device Driver section of the LapLink III documentation. REMEMBER: Any hard disk--regardless of which software programs it contains--should be checked on a regular basis with the DOS CHKDSK command or a disk maintenance utility. This is especially true for portable and laptop computers; portable computers and their hard disks are much more susceptible to damage simply because they are moved more than desktop computers. The CHKDSK command checks a disk for bad sectors and lost clusters and reports its findings. The presence of bad sectors or lost clusters on your disk is an indication of developing trouble. See your DOS manual and computer dealer or user group for more details. OUTLINE OF CONTENTS ------------------- 1. Important Notes 2. Note on Compatibility 3. Video Compatibility 4. Printer Support 5. Additional Technical Information 6. Getting Technical Support 1. IMPORTANT NOTES ------------------ A. LARGE DISK PARTITIONS In general, this version of the LapLink III Device Driver can be used on computers that have hard disks with partitions of 32 megabytes or less regardless of what DOS version was used to create the partitions. When used on hard disks that have partitions larger than 32 megabytes there are some special cases to consider when using the Device Driver only. The main program, LL3.EXE, can be used reliably with any size hard disk, partitioned by any means. 1) This version of the device driver can be used on computers with hard disks that have been partitioned into volumes greater than 32 megabytes when these partitions have been created with MS/PC-DOS 4.01 or Compaq DOS 3.31. 2) Partitions with a sector size of 1K bytes or larger, or greater than 32 megabytes, that have been created with Disk Manager [TM], SpeedStor [TM] or Zenith DOS 3.3 Plus are not supported by this version of the device driver. B. CHKDSK Do not attempt to do a CHKDSK on the same drive that is doing a background print through the device driver. Wait until the printing operation has finished. 2. NOTE ON COMPATIBILITY ------------------------ A. DOS Compatibility This version of the Device Driver will operate with versions of MS/PC DOS from 2.xx to 4.xx, including Compaq DOS 3.31, (subject to the hard disk limitations described above). When you are determining compatibility, consider Compaq DOS 3.31 as equivalent to MS-DOS 4.xx. Some versions of DOS may display a "Sector size too large in file \DD.BIN" error message when the system is booted. This is most likely to occur if the following conditions are present: i) The Lead machine is running a version of MS/PC-DOS 3.3 or 4.xx. ii) The Server machine is using a sector size greater than 512 bytes. iii) The DDINSTAL program on the Lead machine has been used to set the sector size parameter in the "DEVICE=" line in CONFIG.SYS to greater than 512 bytes. Please read pages 139-41 on DOS compatibility in Chapter 7 of the LapLink III manual for more detailed information on how to correct this situation. 3. VIDEO COMPATIBILITY ---------------------- A. High-Resolution Graphics If you are using a program that requires a high-resolution EGA or VGA graphics mode (such as some desktop publishing programs) and you call up the Device Window, the graphics screen for your application may not be restored correctly when you exit the Device Window. You may have to redraw the screen or exit the high-resolution graphics program before you call up the Device Window. B. Video Compatibility between the Two Computers If the computer you are using as the lead does not have the same video capability as the server computer, you may not be able to call up some programs from the server until they are reconfigured for the video capability of the lead computer. 4. PRINTER SUPPORT ------------------ A. Selecting the Printer During Installation The printer you select during installation (lead or server) is the one where printer output will be directed every time you boot your computer, unless you call up the Device Window and change your selection. If you select the Server Printer and that printer is not turned on or the Server program is not running when you give the print command, the Lead computer may appear to lock up. If you have printers connected to both computers, it is recommended that you select the Lead printer during installation. B. Printer Redirection When the user selects the Lead printer, the LapLink Device Driver always directs printer output to LPT1. If the printer on the Lead is connected to LPT2, redirect the output to LPT2 using the DOS Print or Mode commands. See your DOS manual for additional information on these commands, since all versions of DOS may not handle this the same way. C. Printer Error Handling The LapLink Device Driver manages the DOS operation on the lead computer, the server computer and the peripherals connected to each computer. To the extent that DOS provides error messages, the LapLink Device Driver will pass these on to the user. In cases where, for example, the printer selected is out of paper or not on line, DOS does not return an error message, so the LapLink Device Driver has no message to pass to the user. If you are printing inside an application program, the error messages from that application may not be returned. If you give the instruction to print a file on the Lead computer and the Server printer is selected but not available for some reason, the Lead will not give an error message. The Server will be locked with a "Lead computer accessing Server" message on the screen. 5. ADDITIONAL TECHNICAL INFORMATION ----------------------------------- A. Custom Versions of DOS Some hardware manufacturers have customized the MS-DOS operating system that they provide for their machines. Most DOS versions use a sector size of 512 bytes, but some use a sector size of 1024 bytes. DOS 4.xx cannot use any sector size except 512 bytes, so if your lead computer is running DOS 4.xx, you will not be able to communicate with a server computer using a larger sector size. When the Server program (DD.EXE) is run on the NEC MultiSpeed HD with DOS 3.21 a sector size of 1K bytes is indicated. The actual sector size on the hard disk is 512 bytes. This is unique to the NEC implementation of DOS and should not present a problem, except in those cases where the NEC is being run as the Server and the Lead machine is running DOS 4.xx. B. DOS Reserved Device Names For machines running DOS 2.xx, do not use the following reserved words as filenames where printing will be directed: AUX CLOCK$ LPT1 COM1 CON NUL LPT2 COM2 PRN LPT3 For machines running DOS 3.xx or 4.xx, do not use any of the reserved words listed above or, additionally, COM3 or COM4. C. International Keyboard Support The LapLink Device Driver generally works with foreign keyboard layouts selected with the DOS KEYB command. In some cases it may be necessary to reassign the hot key to a key that has not been remapped for the foreign keyboard. The device driver does not work with foreign keyboard layouts selected with the DOS KEYB command on machines running Compaq MS-DOS 3.31. Compaq DOS 3.31 does not implement the KEYB command the same way as other MS/PC DOS 3.xx versions. D. Maximum Number of Drives Supported This version of the Server program can accommodate a maximum of 5 physical/logical drives on the Server computer. This means that drives A, B, C, D, and E are supported. If additional physical/logical drives (F, G, H, etc.) are present on the Server computer, the Server program may not operate correctly. E. Default Server Drive Descriptions The LapLink Device Driver Server program will normally provide a default description for only those disk devices that have been accessed following the system boot-up. In some system configurations, however, the program will show a default description for drives that have not yet been accessed. For example, this happens on a Compaq portable with a Plus Hardcard 10 installed. The user can still add a customized description for disk devices at any time, even if a default description is not displayed. F. Conflicts between Selected Server Drives If you select as one of the Server disk devices a drive that has been previously designated in Server Printer Devices as a drive/path/filename where printing will be directed, then the drive/path/filename will be removed so you can connect that drive as one of the selected drives. The message line will display the error message "Printer filename conflicts with drive you selected." You also cannot select the same drive simultaneously for more than one of the Server disk devices. If you want to change the order of the disk devices, first change them all to Unconnected, then go through the list again selecting them in the order you prefer. G. Server Printer Devices If you elect to print to a filename instead of a device, you will be prompted to enter a filename where the printing will be directed. If you direct printing to a drive that has already been selected as one of the available disk devices, the message line will display the error message "Printer filename you selected conflicts with drive." The conflicting drive in the Server disk device section will then become Unconnected so that printing can be directed there. If you do not enter a drive designation in the "Filename" description, the program will print to the default (boot) drive. H. Changing Server Computers After you have accessed one computer as a server, if you move the LapLink cable to another server computer, type [Ctrl]-[C] on the lead and do a directory of the drives on the new server computer before you use any other Device Driver capabilities. I. Using the Device Driver with Disk Caching Programs When you install the cache, do not install it so that it tries to cache the disks shown by the device driver. J. Using the Device Driver with Multi-Tasking Programs The Server program should not be used with multi-tasking software (such as Desqview, Concurrent DOS 386, etc.) where two copies of the server might be running at the same time. K. Copying Graphics Screens If you want to print a graphics screen that has been saved to disk on the server, use the command "Copy /b ". The DOS print command is not used for printing graphics, only text. L. Environment Variables The LapLink Device Driver will usually find CONFIG.SYS by looking for the "COMSPEC=" environment variable. The Device Driver can also be directed to install the "Device=" line in another location by setting the "LAPSYS=" environment variable. In most normal system configurations it is not necessary to make use of the environment variable and we recommend that you do not use this feature. On some OEM versions of the Device Driver, the "LAPSYS=" variable is used to tell the Device Driver where to install the "Device=" line, because "COMSPEC=" may be pointing at a ROM drive, and the "Device=" line could not be written there. The "LAPSYS=" variable can also be set by the user, but use great care if you intend to override the normal function of the Device Driver in looking for CONFIG.SYS. If you use the "LAPSYS=" variable instead of "COMSPEC=" and you want the Device Driver to be active at boot time, "LAPSYS=" must point to the system configuration file (CONFIG.SYS). The general syntax is "SET LAPSYS=drive\path\CONFIG.SYS" and it can be entered directly at the DOS prompt or included in a batch file. It is possible that DOS will return an "Out of environment space" error message when the "SET LAPSYS=" command is used. If this occurs you must allocate additional memory for the environment. This is accomplished by adding (or modifying) the "SHELL=" line in your CONFIG.SYS file. The general syntax is SHELL=drive\path\COMMAND.COM /P /E:xxxxx where xxxxx is the number of bytes of system memory to be allocated for the environment. The default is usually 160 bytes and setting the value to 256 bytes is sufficient in most cases. See your DOS manual for additional information on these commands, since all versions of DOS may not handle this the same way. M. Path Size for the Device Driver During installation, you will be prompted to type in the path where the Device Driver file will be found. You may indicate a drive and a directory path, or you may simply type in the directory path if the Device Driver file is on the same disk the system boots from. Because the filename is DD.BIN, the maximum length of the path that may be used is 57 characters, not 64 characters as indicated in the manual. N. Memory Requirements The current version of the Device Driver requires a minimum of 49K bytes. Depending on the DOS version and the Server sector size parameter, that can increase to as much as 350K bytes. The following table lists the approximate memory requirements for the device driver with various PC/MS-DOS versions: Server PC-DOS 2.1 MS-DOS 3.3 MS-DOS 4.0 Sector Size Bytes used Bytes used Bytes used -------------------------------------------------- 512 bytes 48992 48672 48768 1K-bytes 56160 58400 2K-bytes 70496 77856 4K-bytes 99168 116768 8K-bytes 156512 194592 16K-bytes 271200 350240 6. GETTING TECHNICAL SUPPORT ---------------------------- If you have a question or need Technical Support, the following sources are available: A. On GEnie type "LAPTOPS" to join the Laptops RoundTable. Then enter the Laptops Bulletin Board and Type "SET 3" to go to Traveling Software Technical Support. Answers to the most frequently asked questions can be found there. To sign up for GEnie call (800) 638-9636 (Voice). B. Traveling Software telephone Technical Support is available from 8:00 a.m. to 5:00 p.m. (Pacific Time) Monday-Friday at (206) 483-8088. Please have your LapLink III serial number ready before calling.