SUMMARY
An issue that confuses some people when installing LAN Manager on an
MS-DOS workstation is the presence of shared RAM. On certain 16-bit
ethernet cards, you can configure your card to use either shared RAM
or DMA. This raises concerns if you are also using EMM386 or any other
expanded memory manager. When using shared RAM, you must exclude an
area or areas of upper memory. In EMM386, this requires an entry where
x=beginning memory address-ending
This address will vary according to the card and to your
configuration. To avoid these complications you can simply disable
shared RAM. This is done with either a setup disk for the network card
or a jumper or DIP switch setting on the card itself.
Some token ring cards (notably IBM types) have an added problem
because you are required to exclude both the ROM and RAM addresses of
the card. These addresses are DIP switch configurable (see the card's
documentation for the settings). Simply put two exclude statements on
the EMM386.EXE command line to exclude both these areas of memory as
follows:
device=emm386.exe x=BEGIN-END x=BEGIN-END
where
Begin = the beginning address
End = the ending address
Example
device=emm386.exe x=c000-c800 x=d000-d800
(This is only an example and should not be used to cure exclusions.
Check your documentation for the actual memory addresses.)
The symptoms of absent exclusions can vary from an inability to bind
the protocol to the card to a more unusual problem with token ring
cards; token ring cards (with EMM386 loaded) without memory exclusions
may fail on cold boot but successfully bind and function on warm
boots.
Remember if you are not running a memory manager like EMM386 then
these are non-issues, but most people use these managers for lower
memory conservation.