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File : MM24INTR.ENG (c) MST Datum: 19 september 1992 Door : Ries Vriend / Ramon van der Winkel / Robbert Wethmar Unauthorized translation by Arnold Metselaar, 1 April 1996 ---------------------------------------------------------- This text contains an explanation about the functions and the use of MemMan. For further information about the internals we point you to the file MM24SPEC.TXT that is also a part of the MemMan-package. That file is overfull with information that is valueable to programmers. For ordinary users it is not very usefull. Contents -------- The files Configurating MemMan Installing MemMan Installing MemMan automaticly Terminate and Stay Resident programs Loading TSR's Viewing TSR's Removing TSR's MemMan BASIC-statements MST's MemMan 2, the MSX Memory Manager ====================================== In the beginning of 1990 MSX Computer Magazine gathered together the best MSX programmers of the Netherlands with the intention to revive the MSX world. De group of programmers got acquainted and ideas were exchanged. It turned out that there was a need for an MSX Memory Manager, a program that administers the memory of an MSX. Two targets were aimed at with the Memory Manager: 1) The searching for and using of memory becomes simpler. The searching is done by MemMan while the using of the memory is made independent of the configuration as much as possible: `Old' expansions, one, two or more mappers, MemMan can handle it all. 2) It becomes possible to have more than one program loaded at the same time without conflicts. Think of RAMdisks, printerbuffers and other background programs. The first target is reached with version 1 of MemMan - introduced on 9 september 1990. Now the second target is reached as well. MemMan version 2 can load more than program `somewhere' in the memory and have them working without the problem of interference. On other computers this technique was already known. Such programs are called TSR's overthere, and here as well: Terminate and Stay Resident programs. Hopefully even more programs will start using MemMan and other programs will be adapted for MemMan. A direct advantage is that the program will be able to work to work with 64 kB modules and even multiple mappers directly, something most existing programs do not do or do not right. MemMan version 2 will be sent into the world as Public Domain, just like the first verion. That means that everybody may use MemMan freely. It is even permitted to sell MemMan as a part of a commercial package. Only in this way the program can become an extension of the MSX-standard. Two packages will be released. The first one is for users of of MemMan. This package will contain MemMan and some tools for the TSR's. The second package contains development tools for and technical documentation about programming TSR's. This last package is not Public Domain. The following people worked on and thougth about MemMan: Ramon van der Winkel Ries Vriend Robbert Wethmar Paul te Bokkel Markus The en some others who helped MemMan to become what it is with their constructive criticism. The files --------- MEMMAN.COM This file contains MemMan itself, one can load it by typing MEMMAN at the DOS prompt. Internally this file is the same as MEMMAN.BIN, only the way of loading is different. MEMMAN.BIN This file contains MemMan itself, one can load it by typing BLOAD"MEMMAN.BIN",R in BASIC. Internally this file is the same as MEMMAN.COM, only the way of loading is different. TL.COM The TSR Loader. With TL TSR's can be loaded into memory from DOS. From BASIC they can be loaded with CMD TL. TV.COM The TSR Viewer. With TV one can get a list of the TSR's that are present in the memory with their full names (TSR ID's) on screen. From BASIC, this can be done with CMD TV. The TSR ID's are neccessary, amongst others to remove a TSR using TK. TK.COM The TSR Killer. With TK TSR's can be removed from the memory from DOS. From BASIC, TSR's can be removed with CMD TK. One can find the name needed to kill the TSR using TV. CFGMMAN.COM The configurating program for MemMan. With CFGMMAN one can configurate MEMMAN.COM and MEMMAN.BIN from DOS. E.g. it is possible to have command executed after loading automaticly. MM24SPEC.TXT The specifications of MemMan 2.4, information for programmers. Only the part with the changes in the latest version may be interesting to users. MM24INTR.TXT An introduction to MemMan 2.4, for those who use MemMan or want to use MemMan applications. This file contains all neccessary information, but nothing about how MemMan works internally. TV.BAS An example of the use of the built-in TSR-commands in BASIC. Not an essential part of MemMan. BK.COM The filecopier that uses MemMan, not an essential part of MemMan. BK-MAN.TXT The Manual of BK.COM, not an essential part of MemMan. others Furthermore some example TSR's (CAPS.TSR and COLOR.TSR) are delivered with MemMan. They are intended as illustration and example and do not form an essential part of MemMan. Configurating MemMan -------------------- MemMan comes in two version: a .BIN and a.COM file. It will be clear that the .BIN version is loaded from BASIC with a BLOAD"MEMMAN.BIN",R intruction, while the .COM can be started from DOS by simply typing MEMMAN. Both version return to BASIC - by a so called `warm boot'- after loading. If the .COM version is started from DOS a command line can be given as an argument. Such a command line contains commands that are executed as if they were typed. A Return can be represented with the @ sign. There can be several @ signs in the command line causing several commands to be executed in sequence. Example: A>MEMMAN _SYSTEM@TL CAPS@ After starting MemMan there will be a return to MSXDOS and the TSR CAPS will be loaded Using CFGMMAN it is possible to give some installation options and a default command line. CFGMMAN can configure both the .COM and the .BIN version. Regarding TSR's the following installation options can be changed: - Default command line This is where the default command line can be entered. This command line is executed after MemMan is installed. The default command line is allways executed after loading the .BIN version. The default command line is not executed if MemMan is loaded from DOS with a command line as an argument. After error messages from MemMan no command line is executed. - Heap size Some TSR's need additional memory in page 3, which they normally do not have access to. The heap is a piece of memory in page 3 that is accessible to TSR's. When a TSR reports that the heap size available is too small this value should be increased. In most cases adding 100 bytes to the heap will fix the problem. If a TSR needs more heap space the manual should state this. Each change of the heap size is only effective after loading MemMan again. - Maximum number of TSR's The number of TSR's that can be loaded by MemMan is limited. If the TSR Loader (TL) gives the message `TSR Table Full' this value should be increased. - Recursion depth When TSR's call eachother or themselves too often the system will hang at some point in time. One can prevent these problems by increasing the recursion depth. TSR's that call themselves should mention this - with the required recursion depth - in the manual. Intalling MemMan ---------------- To load MemMan from MSX-DOS it is sufficient to type `MEMMAN' at the the `>'-prompt. From BASIC the BLOAD"MEMMAN.BIN",R instruction should be executed. After installing MemMan BASIC is started in both cases and the default command line is executed , as given with the configuration program CFGMMAN. De default command line is not executed if MemMan is started from DOS with with another command line as its argument. Version 2 of MemMan occupies not only a piece of the BASIC-memory but also a 16 kB segment. this keeps the memory available in BASIC and MSXDOS as big as possible. The space that is left over in the 16 kB segment is used for TSR's if possible. The amount of BASIC memory that MemMan uses can be influenced by using the CFGMMAN configuration program. When MemMan is installed under DOS2, all segments - except the one that MemMan needs itself - remain available for DOS2. Therefore it is just possible to install MemMan firtst and than a DOS2 RAMdisk. Before installing itself in the memory MemMan will check whether a version of MemMan is already present. In that case the info-lines appear, completed with a messages that MemMan is already installed. Nothing else happens. The command line is executed normally. Installing MemMan automaticly ----------------------------- Like any other program MemMan can be put in AUTOEXEC.BAS or .BAT. There is just one `problem': Installing MemMan causes a `warm boot' that puts the computer in BASIC. This stops the execution of AUTOEXEC. Fortunately there is an easy and sufficient solution to this problem. The trick is that CFGMMAN makes it possible to give MemMan a command line. This command line is executed immediately after MemMan is installed. The first command in the command must therefore be an MSX BASIC commmand. Those who work under DOS, will in general install MemMan from AUTOEXEC.BAT by executing MEMMAN.COM. When other programs need to be installed - like a series of TSR's - , The command line must look like: CALL SYSTEM@GOON@ In this line the @-signs represent Return, and GOON is the name of a batch file that will be executed after MemMan is installed. GOON.BAT can than contain the following commands to be executed. When e.g. the intention is the start TED with a printerbuffer of 48 kB: TL PB PRINT /i48 TED Of course this does require the files TL.COM, PB.TSR, PRINT.COM and TED.COM to be present on the disk. Those who work under Basic, will often want to install some TSR's after the installation of MemMan. In this case this can be done by having a second BASIC program executed after MemMan using the following command line: RUN "GOON.BAS"@ While GOON.BAS can look like: 10 CMD TL ("TRACER",t) 20 CMD TL ("PB",t) 30 NEW To load e.g. the TSR's TRACER.TSR and PB.TSR automaticly after which BASIC programs can be written. Of course it is also possible to load some other TSR's in line 30 and following, to start a program or to ask the user which TSR's should be loaded and not... Those who are only interested in few TSR's can of course do without a GOON.BAT or a GOON.BAS. Loading TSR's from command line of MemMan is no problem at all. _SYSTEM@TL PB@TED@ The command line above returns to DOS after loading MemMan, loads the printerbuffer and starts the word processor TED. This needs TL.COM, but it can easily be done without: CMD TL("PB",T)@_SYSTEM@TED@ Now Pb is loaded from BASIC using MemMan's CMD commands. That is a little bit faster because TL.COM need not be loaded first. Terminate and Stay Resident programs ------------------------------------ Normally a program will not stay in the memory after execution. Programs that do stay are referred to with the abbrevation TSR: Terminate and Stay Resident. Examples of such programs are printerbuffers and RAMdisks. But one can think other applications as well, like a calculator or a calendar that can be activated with a single keypress. In the past TSR's for MSX have been quite rare. The problem was that the memory the TSR uses can be used by other programs as well. There are no possibilities in a standard MSX machine to reseve a piece of memory for a TSR. This problam is eliminated by MemMan. MemMan administers the memory and prevents memory conflicts. Thanks to MemMan it is possible to have more than one TSR in the memory at the same time, where each TSR can be up to 16 kB in size. On a standard MSX loading more than one TSR is cumbersome and only possible if the TSR is not too big. With the introduction of MemMan the MSX gets better TSR features than the commonly esteemed PC. Moreover they are not inferior to the `Desktop Accesoires' that are used on the Macintosh and the Atari ST. Two simple example TSR's are delivered with MemMan. They don't do anything usefull by they demonstrate the potentials of Terminate and Stay Resident programs. The examples are CAPS.TSR and COLOR.TSR. The first makes the Caps indicator blink, while the latter causes the Basic command CMD COLOR to swap the fore- and background color. In the future more and more TSR's will appear with possibilities MSX users could only dream of untill recently. Loading TSR's ------------- TSR programs can be recognized by the extension of the filename; they end on .TSR. These files contain not only program code but also all the information neccessary to install the TSR in the memory. To load e.g. the demonstration TSR `CAPS' - that does nothing but making the Caps indicator blink - , one must type the following under MSX-DOS: TL CAPS Several TSR-filespecifications can be given sequentially. If MSX-DOS2 is used, the subdirectory from where the TSR must be loaded can be given as well. For instance using the following command one can load the TSR `CAPS' and all TSR's with a name starting with `DEMO'. TL CAPS DEMO* `TL' means `TSR-Load', it is the program that load TSR's and places them in the memory. Under BASIC there is also a version of TSR-Load available, see the chapter on `MemMan BASIC-statements'. As soon TL has installed the TSR in the memory, the program shall become active. In the example above that means that the Caps indicator will start to blink and that each keypress will switch the casseterelais. TL is a smart program. As long as there is space left in the MemMan segment TSR's will be placed there. Only if it is really neccessary, a new segment will be used. E.g. when an exceptionally big TSR program must be loaded. When after that a smaller one is loaded TL will first check all existing MemMan segments to see if there is space somewhere. The order in which the TSR are loaded, will therefore have no influence on the amount of memory used. Under MSX-DOS2 TL will use the environment item `TL' to find out where the TSR's are. Harddisk owner only need to put `SET TL=A:\TSRS' in their AUTOEXEC.BAT and all TSR's in de subdirectory A:\TSRS are allways reachable for TL. Supplying the path is than no longer neccessary. Viewing TSR's ------------- At all times it is possible to look which TSR's are active in the memory. That is why the MemMan package contains the utility TV, TSR-View. Using it is the simpicity itself; just type the following at the DOS prompt: TV There will appear an overview of the active TSR's, complete with their full names. These names must be unique for each TSR, en will almost allways contain the initials of the programmer. This name is thus different from the filename! It is this full name - the TSR ID - that is necessary if a TSR must be removed from the memory. Programs that cooperate with TSR's directly can use this name to check whether a TSR is in the memory. Behind the names of the TSR's TV mentions the segment in where they reside and which hooks are linked. The last is only important to programmers. Knowing the segment where a TSR resides is also handsome in other cases. If all TSR's are removed from a segment, that segment will be released and can be used by other programs again. The only exception is segment 0, that contains not only TSR's but also a big part of MemMan itself. Removing TSR's ------------- As mentioned before it also possible to remove TSR programs from the memory. The program needed is named TK, TSR-Kill. TK takes care of removing a TSR neatly. All other other TSR remain working as normal, if the TSR was the only one in a segment, that segment will be released for use by other applications For instance to make the Caps indicator behave normally and stop the blinking, one only needs to remove the TSR involved. You type the following to do this: TK "MJVcapsblink" The full name of the TSR must be given between quotation marks. One can remove several TSR's with one command by entering the names sequentially. E.g: TK "TSR name 1" "TSR name 2" "TSR name 3" TSR-Kill can not only be used to release memory, but also to remove crashed TSR's from the memory. A TSR that, for any reason whatsoever, no longer functions well can often still be removed using TK. After that the TSR can be loaded again. Restarting can be beneficial to both normal programs and to TSR's. MemMan BASIC-statements ----------------------- Starting from version 2.3 MemMan contains some statements and functions that can be used from MSX-BASIC. MemMan has a system TSR for this, named "MST TsrUtils". This TSR has number 0 and can not be removed by TSR-Kill. Below is a description of the available BASIC instructions. The meaning of the used symbols is as follows: [] Anything between square brackets may be left out. <> Descriptions of arguments are between angular brackets. ()", Round brackets must be typed, as well as punctuation and commas. Command: TSR-Load Syntax: CMD TL("<filename>",[T],[<N$>],[<F>]) Type: Statement Example: CMD TL("PB") CMD TL("ALARM",T,,A) Purpose: Load a TSR-file into the memory. <filename> =Name of the TSR-file. Under MSX-DOS2 a subdirectory may be given as well. T = Show the intro-text of the TSR. <N$> = Name of a string-variable in which the TSR ID-name wil be stored. <F> = Variable in which an error code will be stored. If this variable is omitted standard basic error messages will be given in case of loading errors. The error codes are as follows: 0 = TSR loaded succesfully 1 = Installation aborted by the TSR 2 = Structural error in TSR-file 3 = TSR-table full 4 = Hook-table full 5 = No free MemMan segment 6 = Not enough BASIC memory free Command: TSR-Kill Syntax: CMD TK("<TSR ID-name>") Type: Statement Example: CMD TK("MJV printbuf") Purpose: Remove a TSR from the memory. <TSR ID-Naam>. = Identification name of the TSR to be removed. One can get this name by using TSR-View or Find TSR. Command: TSR-View Syntax: CMD TV Type: Statement Purpose: Show an overview with the ID-names of all active TSR's. Command: Find-TSR name Syntax: ATTR$ FT("<TSR ID-name>") Type: Function Example: IF ATTR$ FT("CAPS") THEN CMD TK("CAPS") Purpose: Return -1 if the given TSR is installed and 0 otherwise. <TSR ID-Name> =Identification name of the TSR. Command: Find-TSR number Syntax: ATTR$ FT(<TSR number>) Type: Function Example: N$ = ATTR$ FT(0) Purpose: Give the ID-Name of the TSR with the given number. If the number is greater than the number of active TSR's, an empty string with length 0 is returned. Command: Help Syntax: CMD HELP Type: Statement Example: CMD HELP Purpose: Give information on screen about all the present TSR's that support CMD HELP. This includes in any case the allways present TSR `MST TsrUtils' and e.g. the Tracer. (For programmers: See `hints and directions for programmers' in MM24SPEC.ENG.) ** End **