Simtel MSDOS 1992 June

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ADDRAM 1.0 Copyright (c) 1989 by Marty Del Vecchio Adds memory to DOS using EMS 4.0 memory. Based on the program EEMRAM written by Chris Dunford Table of Contents I. What You Should Have 1 II. What the Program Does 1 III. What You Need 2 IV. How to Do It 3 V. Message Reported by Programs 4 A) ADDRAM 4 B) SUBRAM 5 C) EMSDATA 6 VI. Notices/Disclaimer 7 VII. Questions 7 I. What You Should Have ADDRAM consists of six files: 1) ADDRAM.COM Program that uses EMS 4.0 memory to extend DOS beyond 640K. 2) ADDRAM.ASM Assembly source for above. 3) SUBRAM.COM Program that undoes ADDRAM--it returns DOS to 640K 4) SUBRAM.ASM Assembly source for above. 5) EMSDATA.EXE Program that gives information about the EMS installed in your system. 6) ADDRAM.DOC This file--documentation. II. What the Program Does ADDRAM can increase the size of your DOS memory. DOS is restricted to an arbitrary limit of 640K of memory. This is split up into 10 segments (0 to 9) of 64K each, from address 0000 to 9FFF hex. DOS can only handle one large contiguous memory block, and ordinarily this block is 640K large. This limit is arbitrary because of the placement of video buffers immediately after the reserved DOS space. The EGA/VGA graphics buffer is located at A000. The monochrome text buffer is at B000, and the CGA/EGA/VGA text buffer is at B800. Thus, if you are using a mono card, then there is 64K of address space available right at the end of DOS that should be added to DOS. However, the DOS limit is widely known as 640K, and there are very few memory cards designed to put memory at these locations for use by DOS. However, expanded memory cards that conform to the EEMS (Enhanced Expanded Memory Specification) standard from AST have the ability to map memory at virtually any location in the PC's address space. Chris Dunford wrote a program called EEMRAM (EEMRAM11.ARC) that mapped EEMS memory at the unused video buffers and added it to DOS. When EMS 4.0 was introduced, it was a combination of "normal" EMS 3.2 (the type of memory provided by the Intel Above Board, for example) and "enhanced" EMS (AST's memory cards). Part of the EMS 4.0 spec says that cards may be able to map memory at different locations in the PC address space, just like EEMS cards. This program is designed for EMS 4.0 cards that can do this. However, it must be noted that this capability is an OPTION in the EMS 4.0 spec. Thus, there are expanded memory cards that are advertised as "EMS 4.0" cards. However, because they cannot map memory wherever it is needed, they are insufficient for the purposes of this program. For this program, you need a "true" EMS 4.0 card. For more Page 1 particulars, see below. Page 2 III. What You Need ADDRAM is designed to extend DOS beyond 640K whenever possible, using EMS 4.0 memory. It does this by addressing EMS memory into unused video buffer memory. ADDRAM can only increase DOS' memory size under certain conditions: 1) You must already have exactly 640K of DOS memory installed. No more, no less. 2) The machine MUST have an EMS 4.0 memory card that can map expanded memory into the A000 and B000 segments, where video memory is located. The vast majority of EMS cards available cannot do this, because they were designed prior to the release of the EMS 4.0 specification. This program requires functions found in EEMS cards, and NEWLY-DESIGNED EMS 4.0 cards. Many EMS cards are sold today as "EMS 4.0" capable that cannot perform all of the EMS 4.0 functions needed for this particular purpose. The following paragraphs represent my personal experience in working with memory cards, and their fitness for a particular purpose. This should not be interpreted as a general view of the cards discussed--this is only a discussion of their suitability for use by ADDRAM. All of the AST Rampage products (Rampage 286, Rampage 286 Plus, etc.) have the required capability, since they are true EEMS/EMS 4.0 cards. However, you need to get the EMS 4.0 driver from AST for these products--ADDRAM does not work with a plain EEMS driver. If you only have the old EEMS driver, use EEMRAM11.ARC by Chris Dunford. The Intel Above Board products (Above Board, Above Board Plus) do not have the capability needed by ADDRAM. The Above Board is an old-style EMS card, and the new Above Board Plus is prohibited from addressing memory in the A000 and B000 segments to prevent conflicts with video memory. Thus, they cannot be used by ADDRAM to add memory to DOS. The Charge Card from All Computers, Inc. can be used. Use the device driver "ALLEMM4.SYS" included on the ALL disks. QEMM from Quarterdeck and 386 to the Max from Qualitas can also be used, but they can automatically add memory to DOS if requested. This program should be unnecessary if you have either of these products or a similar product. The program EMSDATA.EXE, included here, can help you determine if your EMS card can be used. 3) There must be unused memory starting at segment A000. If you Page 3 have an EGA or VGA system, you cannot add memory to DOS unless you use the All Charge Card. This is because EGA/VGA cards use the A000 segment for high resolution graphics video buffers, and thus the EMS card cannot address memory there. If you have the Charge Card, and you do not use your EGA/VGA in graphics mode, but only in text mode, you can overcome this restriction by adding "i=A000-AFFF" to the command line. This takes away the graphics buffer and gives it to DOS, and thus any program that tries to use EGA/VGA graphics will crash your system. It is up to you to decide if you want to make this tradeoff. However, beware that some EGA cards use the A000 segment even when not in graphics mode. You will have to experiment with your particular card to see if this space can be used. Such results cannot be guaranteed. If you have a standard monochrome or Hercules monochrome video card, then you can add 64K to DOS, for a total of 704K. If you have a CGA system, you can add 96K to DOS, for a total of 736K. IV. How to Do It First, you have to ensure that your card can map memory into the A000 and B000 segments. Run the program EMSDATA.EXE to see if your EMS card can currently do this. Some EMS software drivers (the driver you load in CONFIG.SYS) must be explicitly told on their command lines that they can use this memory for mapping. For example, if you have a monochrome system and an AST Rampage 286, you have to add the following to your 'DEVICE = REMM.SYS' command line: "/i=A000-AFFF". This tells the EMS driver that it is OK to address memory into this region. If you have a CGA, you must specify "/i=A000-B7FF". Run the program EMSDATA.EXE to determine if your EMS driver can map memory into these locations--the last paragraph it prints out deals with this matter. Once you have ensured that the EMS card can map memory into the video buffer space, you must run the program ADDRAM.COM. ADDRAM.COM is the program that actually maps memory into the video buffer space and tells DOS that it is there. To run this program, just type 'ADDRAM' at the DOS prompt. It will automatically add as much memory as possible, up to 96K, to DOS. It will report on its success or failure. If you want to limit the amount of memory added to DOS for some reason, you can do so by specifying the maximum number of EMS pages (16K each) on the command line. For example, to add only 32K of memory to DOS, you would type 'ADDRAM /2' on the command line. Page 4 V. Messages Reported by Programs A) ADDRAM Here is a list of the messages reported by ADDRAM: "Expanded Memory Manager not found--no EMS installed." This message indicates that no expanded memory was found in your system. If you have an EMS card in your machine, be sure to add the device driver statement in your CONFIG.SYS file. See the instructions that come with your EMS card to do this. "Expanded Memory Manager reports an error." This message indicates that the EMS software is in a state of error. This may be a software or hardware error--run EMSDATA.EXE to determine the cause. Because of this error, ADDRAM cannot add memory to DOS. "This program requires version 4.0 expanded memory." As discussed above, the EMS driver must be version 4.0 or above. "This program requires exactly 640K of installed DOS memory." As discussed above, this program cannot be used if your machine has more than 640K or less than 640K of DOS memory installed. If you have more, then you don't need this program. If you have less, then you should use your EMS card to backfill DOS to 640K. To do this, see your EMS card's instruction manual. "This program's memory allocation block is not the last in DOS' chain. Cannot change memory of not at end." This message indicates that the memory block allocated to ADDRAM is not at the END of DOS. You might get this message if you try to run ADDRAM from inside of another program, such as the DOS shell of Lotus 1-2-3. If you get this message, exit the program you are currently in and try again. "Expanded Memory Manager cannot map memory at segment A000." As discussed above, your EMS card must be able to map memory at segment A000 in order for it to be added to DOS. This is because DOS can only work with one large contiguous block of memory. "Not enough expanded memory available." If there is not enough expanded memory free, you will get this error. If you are adding 64K to DOS, then you naturally need to Page 5 have 64K of expanded memory available. Run the program EMSDATA.EXE to determine the amount of free expanded memory. "Error while mapping expanded memory at A000." This message indicates that the EMS driver reported an error while memory was being mapped at A000. This may be a hardware or a software error--in any case, no memory can be added to DOS. "Error assigning name to expanded memory handle." Under EMS version prior to 4.0, a chunk of EMS memory was only known by a number (known as a handle). With EMS 4.0, a program can identify its chunk of memory with an 8-character name. ADDRAM assigns the name "ADDRAM00" to its memory. This is so that SUBRAM can later find it and deallocate it. This message indicates that an error occurred wile assigning this name to the EMS memory. In this case, no memory can be added to DOS. "ADDRAM's name already in use by another handle." This message indicates that another program has used the name "ADDRAM00" for its EMS memory. In this unlikely case, no memory can be added to DOS. "XX KB memory successfully added to DOS." This message indicates success. "XX" will be a number, either 16, 32, 48, 64, 80, or 96. This specifies the amount of memory added to DOS. To verify that this is the case, run DOS' 'CHKDSK' program. At the end it will report the amount of DOS memory. B) SUBRAM SUBRAM can be used to un-do the effects of ADDRAM. It will restore DOS to 640K and release the expanded memory used. Here are the messages returned by SUBRAM: "Only 640KB DOS memory--no memory has been added by ADDRAM." This message indicates that DOS is currently at 640K, and thus ADDRAM has not been run successfully. "Expanded Memory Manager not found--no EMS installed." This message indicates that no EMS memory is installed in the system, and thus ADDRAM was not run successfully. "No memory has been added by ADDRAM." This message indicates that, although EMS memory is present, Page 6 ADDRAM has not been run successfully to add memory to DOS. "This program's memory allocation block is not the last in DOS's chain. Cannot change memory if not at end." This message indicates that the memory block allocated to SUBRAM is not at the END of DOS. You might get this message if you try to run SUBRAM from inside of another program, such as the DOS shell of Lotus 1-2-3. If you get this message, exit the program you are currently in and try again. "Error deallocating EMS memory." This message indicates that an error occurred while SUBRAM was freeing the EMS memory added by ADDRAM. This indicates a malfunction in the EMS driver. "DOS memory reset to 640KB, EMS memory freed." This message indicates success--DOS was restored to 640KB, and the EMS memory added by ADDRAM was freed for use by other programs. C) EMSDATA EMSDATA.EXE is designed to tell you about your current EMS configuration. Just type 'EMSDATA' at the DOS command prompt. The program's output is generally longer than one screen--you can pause it by hitting Ctrl-S (the Ctrl key and the S key at the same time). You can resume the program by hitting any other key. This program will tell you numerous things about your EMS, including the software version number, its current state, the EMS page frame segment address (where application programs address EMS memory), the total amount of EMS memory and amount of free EMS memory. EMSDATA will also give a list of the allocated handles (blocks of EMS memory in use by programs), the pages and bytes allocated to each, and if the EMS is version 4.0 or higher, the name assigned to each handle. It is rare for a program to assign a name to a handle, but ADDRAM assigns the name 'ADDRAM00' to its handle. EMSDATA will also give technical information about your EMS hardware, include the raw page size (16KB is the standard EMS page size, but some implementations have smaller sizes), total number of raw pages, and number of free raw pages. EMSDATA will report the number of "additional register sets." This refers to the number of mappings the EMS hardware can keep track of in addition to the current mappings. Multitasking programs such as Desqview use alternate register sets for quick switching of tasks. This is one way to tell if you have a true EMS 4.0/EEMS system. If Page 7 this number is 0, then you most likely do not. If this number is greater than 1, then you most likely do. The context save area size refers to the amount of memory a program must use to save the current page mapping context. Resident programs that use EMS memory (such as Sidekick Plus, and RAM disks and disk caches that uses EMS) must save the current context before using their EMS memory. The smaller this area is, the faster they can operate. The number of DMA channels available on an EMS board can affect its performance in copying memory from expanded to conventional memory. The next paragraph printed by EMSDATA discusses whether or not your EMS card has been used to backfill DOS to 640K. If it has, then programs like Desqview can use this page size to multitask programs in. If not, then Desqview cannot easily run multiple programs in expanded memory in this manner. The next paragraph (and chart) discuss the exact memory locations at which your EMS card can and cannot address memory. The final paragraph discusses whether or not your EMS card is currently capable of mapping memory at segment A000, and thus whether it can potentially be used by ADDRAM. Again, these values may be changed, depending on your EMS card, by adding parameters to the device driver statement in your CONFIG.SYS file. See your card's manual for more details. VI. Notices/Disclaimer This program is released to the public domain for free use by anybody. However, it cannot be sold at any price. The author, Marty Del Vecchio, hereby disclaims any warranties, express or implied. This program is not guaranteed to work at all. Its author cannot be responsible for any loss or any damage of any kind resulting in its use. Use at your own risk. All of the brand names used are trademarks and/or copyrights of the appropriate companies. VII. Questions If you have any questions or bug reports, you can contact me at home at (508) 820-1544. Or you can find me at the Channel 1 BBS system in Boston. The number there is (617) 354-8873. Leave a message in the main conference for 'MARTY DEL VECCHIO'--note the space! Page 8