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Readme.txt
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Readme.txt
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1. About
HimemX is a XMS memory manager. It's derived from FreeDOS Himem
(short: FDHimem) with bugfixes, optimizations and extensions.
To see its usage just run HIMEMX.EXE from the command line.
2. HimemX and HimemX2
Currently there are 2 versions of HimemX supplied, HimemX and HimemX2.
HimemX2 uses a different strategy when it comes to extended memory block
allocations. This difference is only relevant if extended memory is
scattered in multiple blocks, as it is the case on newer machines.
Then, generally, HimemX2 tends to allocate memory blocks from low addresses
to high addresses, while the addresses of memory blocks allocated by
HimemX are a "wild" mix.
Since the allocation strategy of HimemX is the one also used by MS Himem,
it is probably to be prefered. OTOH, MS Himem is from a time when extended
memory wasn't scattered, so this argument hasn't much weight - there are
no known incompatibilities of HimemX2.
In any case, HimemX2 most likely is a cure if Jemm386 reports
"Warning: address of allocated EMB (=xxxxxxxx) is beyond 16 MB".
This warning indicates that Jemm386 couldn't locate its DMA buffer in an
address range where ISA DMA is working. ISA DMA is used by the floppy
controller and may be used by the parallel port or ISA expansion cards.
These are now virtually obsolete devices, but to be sure, use HimemX2 if
you get the warning mentioned above - the warning is displayed by
Jemm386 v5.80+ only.
3. UMBM
To find out the purpose of UMBM.EXE, just run it from the command line.
4. License
All changes done for HimemX are Public Domain. However, since HimemX is
derived from FD Himem, the FD Himem copyrights do apply. FD Himem is
copyright Till Gerken and Tom Ehlert, with GPL and/or Artistic license.
UMBM.EXE is Public Domain. The source code UMBM.ASM is supplied with
Jemm.
Japheth