APPLICATION NOTE #194 USING A RAM DRIVE WITH XYWRITE This application note contains some tips for using expanded memory as a RAM drive with XyWrite III Plus. It addresses those questions most frequently asked of XYQUEST's Technical Services department regarding RAM drives. It assumes you have set up the RAM drive according to instructions in your DOS manual. The main reason to use a RAM drive is to speed up access time--access to RAM is faster than is access to a physical drive. Using a portion of RAM as a RAM drive gives you the functionality of disk storage with the speed of RAM access. Following are some tips on using a RAM drive most effectively with XyWrite. All are aimed at minimizing XyWrite's disk access. 1. Make certain that the RAM drive is included in your DOS path statement. Make sure it is listed before the physical drive/subdirectory that contains XyWrite. For example, if E is the RAM drive, the following is correct: path c:\;e:\;c:\xy If the RAM drive is listed after the physical drive/subdirectory containing XyWrite, when XyWrite uses the path statement to locate files it will always find them on the physical drive first and stop searching. Therefore, this is wrong: path c:\;c:\xy;e:\ Refer to your DOS manual for more information on path statements. 2. Set the RAM drive as the default drive. XyWrite creates temporary files (such as overflow, PRINT.TMP, S.TMP) there. For example, the following entry in STARTUP.INT sets drive E as the default drive: default dr=e An added advantage is that these temporary files are automatically deleted when you quit XyWrite (see #), which means you no longer need to delete them from a physical drive. 3. If you use the thesaurus often, copy the two thesaurus files (WORD.OVR and WFBG.SYN) to the RAM drive. For example: F5copy word.ovr e:\ F5copy wfbg.syn e:\ Since these files are fairly large, don't waste RAM drive space with them unless you use the thesaurus frequently. 4. Copy Help files or the A La Carte Menu file (ALACARTE.MNU) to the RAM drive. For example: F5copy long.hlp e:\ OR F5copy short.hlp e:\ OR F5copy alacarte.mnu e:\ Since Help and Menu files are very large, XyWrite never keeps the whole file in memory. The first time you load a Help or Menu file, XyWrite creates an internal index of the file and stores the index at the bottom of the file. This index, and certain types of Help frames, are all that actually load into memory, which allows a very large Help or Menu file to consume very little memory. When you access Help or the A La Carte menu, XyWrite checks the index, much as you check the index of a book, to determine where to get the information. It then refers back to the Help or Menu file stored on disk to get the information to display on the screen. Since going back to a RAM drive rather than a physical disk is faster, you can access Help and the menus faster. 5. Do not copy EDITOR.EXE to the RAM drive unless you use the SAVEC (Save Code) or the UNLOAD command. EDITOR.EXE is loaded entirely into conventional memory; XyWrite does not need to access the disk for executable code unless you have specifically released code. If you use SAVEC, make sure you have specified with the default DR setting the RAM drive as the place to save to. If you use UNLOAD, copy EDITOR.EXE to the RAM drive first. 6. Do not copy your customized printer, keyboard, or spelling files to the RAM drive unless you frequently modify and reload them. Customized files get loaded entirely into conventional memory, and any further disk access is not needed. If you decide to copy some of them to the RAM drive because you plan to modify and reload them frequently, see #. 7. Remember, any files you place in the RAM drive are lost when you turn off or reboot the computer. If you use the RAM drive for text files, make certain you copy them to a physical drive before quitting XyWrite or rebooting.