mday@ohs.UUCP (Matthew T. Day) (07/22/89)
I have recently downloaded a program called EMS40 from a local BBS, and I would like to know how and if it works. What it supposedly does is emulate an EMS board, thereby making your extended memory into expanded RAM. Since here on my IBM/AT I have 512K main and 512K extended, I would like to somehow tack that extended memory in with my main. Currently I'm using it as a RAM disk with VDISK.SYS, but to be able to move myself up to at least 640K would be wonderful. Has anyone got an idea on either how EMS would work for me or another application that I could use? -- +----------------------------------------------------------+-----------------+ | Matthew T. Day, Orem High School, Orem, Utah | "He who laughs, | | Internet: mday@ohs.uucp UUCP: ..!uunet!iconsys!ohs!mday | lasts." | +----------------------------------------------------------+-----------------+
psfales@cbnewsc.ATT.COM (Peter Fales) (07/23/89)
In article <312@ohs.UUCP>, mday@ohs.UUCP (Matthew T. Day) writes: > I have recently downloaded a program called EMS40 from a local BBS, and I > would like to know how and if it works. What it supposedly does is emulate > an EMS board, thereby making your extended memory into expanded RAM. Since > here on my IBM/AT I have 512K main and 512K extended, I would like to somehow > tack that extended memory in with my main. Currently I'm using it as a RAM > disk with VDISK.SYS, but to be able to move myself up to at least 640K would > be wonderful. Has anyone got an idea on either how EMS would work for me or > another application that I could use? I raised the question a while back and I believe the consensus then was: No, you cannot use software to map extended memory into the 0-640K range. The way these programs work is by stealing a 64K block of memory from the 640K (in your case 512K) to use as "bank switched" memory. Then as your RAMDISK (or whatever) needs access to extended memory, 16K blocks are copied between main memory and extended memory. This is much slower than the hardware bank switching used by true EMS boards, but it does provide a standard interface to extended memory for any program which can use EMS. -- Peter Fales AT&T, Room 5B-420 2000 N. Naperville Rd. UUCP: ...att!ihlpb!psfales Naperville, IL 60566 Domain: psfales@ihlpb.att.com work: (312) 979-8031
jms@hcx.uucp (Michael Stanley) (07/23/89)
In article <312@ohs.UUCP>, mday@ohs.UUCP (Matthew T. Day) writes: > I have recently downloaded a program called EMS40 from a local BBS, and I > would like to know how and if it works. What it supposedly does is emulate > an EMS board, thereby making your extended memory into expanded RAM. Since > here on my IBM/AT I have 512K main and 512K extended, I would like to somehow > tack that extended memory in with my main. Currently I'm using it as a RAM > disk with VDISK.SYS, but to be able to move myself up to at least 640K would > be wonderful. Has anyone got an idea on either how EMS would work for me or > another application that I could use? This program sounds like it came from PC magazine volume 8 issue 12 June 27, 1989. This issue and the two prior ones: (vol 8 num 10 may 30, 1989 and vol 8 num 11 june 18, 1989) contain the three parts of an article which do a good job of introducing one to using extended memory from programs which run in PC/MS-DOS. The third issue mentioned include the programs EMS4.0.SYS and XMSDISK.SYS (in program source form) which both make use of extended memory. These two programs should provide working examples to supplement the three articles. Michael Stanley jms@hcx.uucp