On 2004-03-17, Arkady V.Belousov wrote: >> device=3Demm386.exe noems >> mema /e -> MEM: error: EMM call 41h > > This is because EMM returns no page frame. Well... May be, this > shouldn't be an error (I remember someone says that we may work with > EMS without page frame).
It is possible to use EMS without a 64 Kb page frame since EMS 4.0. That's what the FRAME=NONE parameter is good for. In EEMS and EMS 4.0, 16 Kb pages can be mapped in (almost) anywhere you like in the first 1 Mb, so you can use EMS to backfill memory. For example, on machines which have only 512 Kb conventional memory, you could permanently map in EMS pages between 8000h..9FFFh in order to gain another 128 Kb of conventional memory. You could also use this to flip between several sets of pages tiling most of your real-mode memory environment in order to aid faster real-mode multitasking (DESQview and old versions of Windows used this). Finally, if you align your data buffers to 16 Kb boundaries within your application (or driver) you can map in a 16 Kb EMS page there. Neither of these EMS access methods /requires/ a page frame, so if none of your applications would make use of the page frame (most EMS-aware software, however, does, as EMS 3.x did not provided this facilty!), you could continue to use EMS but disable the page frame in order to re-gain 64 Kb of addressable real-mode memory, which you could use for other purposes, for example place UMBs there... (On the other hand, you could (almost) just as well lock down memory in an existing page frame and convert it to EMS - for example the DR-DOS HIMEM.SYS driver can do this with its /CHIPSET=EMSALL and EMSUMB parameters). Greetings, Matthias -- <mailto:[EMAIL PROTECTED]>; <mailto:[EMAIL PROTECTED]> http://www.uni-bonn.de/~uzs180/mpdokeng.html; http://mpaul.drdos.org "Programs are poems for computers." ------------------------------------------------------- This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id=1470&alloc_id=3638&op=click _______________________________________________ Freedos-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/freedos-user
