@BANNER = Memory Requirements @APP NOTE = Application Note #2 @NAME = Features: Screen drivers Memory This document describes the memory requirements for three common screen drivers: EGA, VGA, and VGA high resolution. Ventura Publisher version 2.0 requires more conventional memory than version 1.1. Consequently, more attention must be paid to computer configurations. The most critical elements are: drivers in the CONFIG.SYS file, screen driver installed for Ventura Publisher, and use (or non-use) of EMS and/or XMS (e.g., HIMEM.SYS) drivers. This note summarizes the actual memory requirements for the most common configurations. The requirements shown here were based on actual tests performed on a Compaq 286 computer. Before each test was performed, a DOS CHKDSK was executed to show the total amount of conventional memory remaining. Once Ventura Publisher was loaded, the hidden diagnostic menu (activated by selecting the word VENTURA in the Desk menu) was used to show how much conventional memory was remaining after Ventura Publisher was loaded. A note was also made if the Screen Buffer had already been pirated in order to make additional memory available. Finally, using these figures, a calculation was made to determine how little conventional memory could be allowed and still be able to run Ventura Publisher without needing to use the /A or /F switches. The /A switch allows up to 32K bytes of memory to be returned to conventional memory (and taken from the graphic buffer) and the /F switch can be set to make as little as 32K available to Ventura Publisher's screen font area (see Appendix A of the Ventura Publisher Reference Guide for more details). Since Ventura Publisher will automatically attempt to rob up to 16K from the screen graphic buffer if it senses a low memory situation (reducing the screen buffer from 68K to 52K) a total of up to 52K (32K for the /A switch and 52-32=20K by setting /F=32) of additional conventional memory can theoretically be made available to Ventura Publisher by specifying /A=32 and /F=32 in the VP.BAT file. Put another way, in theory you could have a CHKDSK amount of 52K less than the figures shown and still run the program. In practice, however, most printer drivers other than PostScript will not operate with the /A switch set higher than 16, and the screen drawing performance will begin to suffer if you specify /F values less than 52K. Therefore, these CHKDSK amounts should be taken as the minimum practical amounts for most situations, with the possibility of getting at least 16K additional with most printers, and 32K for PostScript printers by specifying either /A=16 or /A=32 in the VP.BAT or VPPROF.BAT file (see Appendix A of the Reference Guide). Note that the 16 color drivers CAN be run without EMS (contrary to the note at the bottom of the first page of the display selection screen which appears during Ventura Publisher's VPPREP installation program), but you cannot have ANY drivers or background software in your computer. For all tests summarized in this document, the CONFIG.SYS file had only a FILES and BUFFERS statement (plus HIMEM.SYS and EMS drivers when appropriate). The AUTOEXEC.BAT file had nothing in it. @PAGE BREAK = The lessons to be learned from the numbers on the next pages are as follows: You can run both the base and professional extension to Ventura Publisher without EMS memory with any screen driver, but with the 16 color VGA (or EGA) driver you will be on the verge of not running unless you strip your CONFIG.SYS file clean. The other lesson is that EMS and HIMEM.SYS work wonders for memory problems. This is because HIMEM.SYS adds almost 64K of apparent conventional memory. EMS helps in a number of ways. First it lets between 48K and 80K of system software be loaded into EMS memory, thus freeing a corresponding amount of conventional memory. Second, it allows Ventura Publisher Professional Extension to run with only 48K of conventional memory remaining (the base product still requires 100K). All this extra memory lets you place disk caches, TSRs and other drivers into your system and still be able to satisfactorily run Ventura Publisher. Alternatively, you can use all this conventional memory to INCREASE the /F amount (up to /F=168) to improves screen drawing speed when using many fonts on a page or when using very large (e.g., 72 point) fonts. With the Professional Extension there is no performance penalty for operating with little conventional memory because all temporary buffers and all portions of the document will be placed in EMS memory. By contrast, the less conventional memory available to the base product, the slower the system becomes when working with long documents. Computer: Compaq 286 Files = 20, Buffers = 20 DOS 3.20 Display card: AST VGA multi-mode card @TABLE = <~> Test #1: Conventional Memory Only. CHKDSK shows: 599,600 @TABLE = Monitor Display driver name External Memory Minimum CHKDSK Remaining to let program run Professional Extension @TABLE = EGA (two color) SD_EGAH5.EGA 113,576 570,024 @TABLE = VGA (two color) SD_VGA_5.VGA 112,056 571,544 @TABLE = VGA (sixteen color)* SDFVGAH5.VGA 103,112 596,488 Base Product @TABLE = EGA (two color) SD_EGAH5.EGA 127,368 556,232 @TABLE = VGA (two color) SD_VGA_5.VGA 125,848 557,752 @TABLE = VGA (sixteen color)* SDFVGAH5.VGA 116,904 582,696 * indicates Screen buffer already reduced from 68K to 52K. @TABLE = <~> Test #2: HIMEM.SYS. CHKDSK shows: 597,728 @TABLE = Monitor Display driver name External Memory Minimum CHKDSK Remaining to let program run Professional Extension @TABLE = EGA (two color) SD_EGAH5.EGA 173,496 508,232 @TABLE = VGA (two color) SD_VGA_5.VGA 171,976 509,752 @TABLE = VGA (sixteen color) SDFVGAH5.VGA 147,032 534,696 Base Product @TABLE = Monitor Display driver name External Memory remaining @TABLE = EGA (two color) SD_EGAH5.EGA 175,000 506,728 @TABLE = VGA (two color) SD_VGA_5.VGA 173,480 508,248 @TABLE = VGA (sixteen color) SDFVGAH5.VGA 148,536 533,192 @TABLE = <~><~> Test #3: EMS memory. CHKDSK shows: 589,360 @TABLE = Monitor Display driver name External Memory Minimum CHKDSK Remaining to let program run Professional Extension @TABLE = EGA (two color) SD_EGAH5.EGA 156,568 464,792 @TABLE = VGA (two color) SD_VGA_5.VGA 156,008 465,352 @TABLE = VGA (sixteen color) SDFVGAH5.VGA 154,104 467,256 Base Product @TABLE = EGA (two color) SD_EGAH5.EGA 175,000 498,360 @TABLE = VGA (two color) SD_VGA_5.VGA 173,480 499,880 @TABLE = VGA (sixteen color) SDFVGAH5.VGA 148,536 524,824 @TABLE = <~> Test #4: EMS memory + HIMEM.SYS. CHKDSK shows: 587,488 @TABLE = Monitor Display driver name External Memory Minimum CHKDSK Remaining to let program run Professional Extension @TABLE = EGA (two color) SD_EGAH5.EGA 216,488 403,000 @TABLE = VGA (two color) SD_VGA_5.VGA 215,928 403,560 @TABLE = VGA (sixteen color) SDFVGAH5.VGA 214,024 405,464 Base Product @TABLE = EGA (two color) SD_EGAH5.EGA 195,544 475,944 @TABLE = VGA (two color) SD_VGA_5.VGA 194,984 476,504 @TABLE = VGA (sixteen color) SDFVGAH5.VGA 193,080 478,408