Analysis of information sources in references of the Wikipedia article "High memory area" in English language version.
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NWDOSTIP.TXT is a comprehensive work on Novell DOS 7 and OpenDOS 7.01, including the description of many undocumented features and internals. It is part of the author's yet larger MPDOSTIP.ZIP collection maintained up to 2001 and distributed on many sites at the time. The provided link points to a HTML-converted older version of the file.) {{cite newsgroup}}: CS1 maint: deprecated archival service (link) (NB. Gives a comprehensive overview on the history and "nature" of the HMA and the non-obvious design constraints to be observed when developing resident system extensions to be loaded into the HMA. It also describes how to address these issues using stubs, backdoors, and intra-segment offset relocation, a method used by DR-DOS drivers capable of relocating into the HMA and similar to a (more sophisticated) method used as the basis for the dynamic dead-code elimination in the author's FreeKEYB driver.){{cite newsgroup}}: CS1 maint: deprecated archival service (link)[…] MS-DOS 7.0+ adds INT 21h/AX=4A03h and INT 21h/AX=4A04h. RBIL61 INT 21h/AH=52h has some info on the MS-DOS 7.0+ HMA MCB chain […] HMA relocation for TSRs makes much sense for DR-DOS: Although you can load large parts of the BIOS and BDOS, the resident part of the shell, the BUFFERS, and DR-DOS TSRs like SHARE, KEYB, and NLSFUNC (and in some issues parts of TASKMGR and NWCACHE) into the HMA, there is usually still free space available, typically around 10 Kb (up to ca. 20 Kb when you use a 3rd party shell). It also makes sense for MS-DOS 5.0 – 6.22 and PC DOS up to 2000, which typically leave 4 – 7 Kb of the HMA memory unused (SHARE, KEYB, and NLSFUNC cannot load into the HMA, but DBLSPACE and HIMEM can to some extent). Available HMA space can be rather tight with MS-DOS 7.0+, since this issue introduced a new and for the most part undocumented RMD data structure usually located in the HMA. The kernel collects and records configuration and Real Mode Driver data during boot (type of driver, interrupts hooked by driver, CONFIG.SYS line of invocation, etc.) and stores this information in an […] complicated […] and […] growing data structure. Presumably this info is meant to be used by the Windows core to get a better picture of the loaded Real Mode drivers instead of treating DOS as a monolithic block, or even […] attempt to unhook or unload some of them, however, it is only used to a very limited extent (for example you can see some of the info reflected in the log files created on Windows 9x startup, and some parts of the Windows configuration manager also make use of it), leaving room for speculation much beyond the technical side - in particular because nothing of the interesting stuff is documented… […]
{{cite web}}: CS1 maint: deprecated archival service (link)[…] some issues of DISPLAY.SYS (of PC DOS 7/2000, for example) store the currently unused fonts in XMS memory. Some earlier issues of MS-DOS/PC DOS DISPLAY.SYS seem to have had a facility to store them in the HMA […]
[…] DOSKEY.COM […] Move code to HMA if available. […] SHARE.EXE […] Move code to HMA if available and added /NOHMA option force loading low. […]
[…] ANSIPLUS's code cannot be loaded to the HMA under MS-DOS 7 (Windows 9x only) because there apparently is not enough unused HMA memory available. […]
[…] One of the most important stimulanta for adding features was competitive pressure from DRDOS 5.0, which we first learnt of in the spring of 1990. The DRDOS feature set led us to add UMB support, task swapping, and Undelete. […] Considerable amounts of the team's management attention was diverted to new features such as file transfer software, undelete and network installation […] Eventually this situation reached a crisis point at the end of July 1990, and, led by BradS, the team's management spent an arduous series of meetings nailing down a schedule and process for closing the project down […](1+32 pages)
NWDOSTIP.TXT is a comprehensive work on Novell DOS 7 and OpenDOS 7.01, including the description of many undocumented features and internals. It is part of the author's yet larger MPDOSTIP.ZIP collection maintained up to 2001 and distributed on many sites at the time. The provided link points to a HTML-converted older version of the file.) […] some issues of DISPLAY.SYS (of PC DOS 7/2000, for example) store the currently unused fonts in XMS memory. Some earlier issues of MS-DOS/PC DOS DISPLAY.SYS seem to have had a facility to store them in the HMA […]
[…] DOSKEY.COM […] Move code to HMA if available. […] SHARE.EXE […] Move code to HMA if available and added /NOHMA option force loading low. […]
[…] ANSIPLUS's code cannot be loaded to the HMA under MS-DOS 7 (Windows 9x only) because there apparently is not enough unused HMA memory available. […]
[…] One of the most important stimulanta for adding features was competitive pressure from DRDOS 5.0, which we first learnt of in the spring of 1990. The DRDOS feature set led us to add UMB support, task swapping, and Undelete. […] Considerable amounts of the team's management attention was diverted to new features such as file transfer software, undelete and network installation […] Eventually this situation reached a crisis point at the end of July 1990, and, led by BradS, the team's management spent an arduous series of meetings nailing down a schedule and process for closing the project down […](1+32 pages)