Campbell PC208W, Instruction Manual

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Appendix D. Card Services Driver Software Notes
PC208W, Version 3.3, Instruction Manual D-3
Although the SMS PC Card Setup program may be all that is required for
successfully setting up and running PC Cards with SMS, the following notes
are provided for a more detailed understanding of the way PC Cards are used.
These notes are intended as a supplement to the documentation shipped with
any PCMCIA drivers you may have.
For some Card Services without MTD support, SMS needs a memory range of
32K allocated to Card Services. It uses the 32K memory to read and write to
the card, while newer versions of Card Services configure this for you
automatically, some older versions require the user to set this up. Notes are
given below on how to set up some older versions of Card Services.
Card Services has the ability to map a region of the PCMCIA card to PC
address space in the high-memory area. This is the same address space which
is mapped to extended memory by EMM386 for programs loaded high with
DEVICEHIGH or LOADHIGH. If all of this address space is allocated, then
Card Services will not be able to map regions to SRAM cards, and SMS will
fail with an error. The following information explains what to do if you have
this problem.
Card Services does not use the actual memory in the high memory area, but it
does use that address space. There is no memory in that address space. If you
have EMM386 loaded (which you will have if you load other drivers, etc., into
high memory) you must exclude an area of memory for Card Services use.
The line in your CONFIG.SYS which sets up EMM.386 will look something
like:
DEVICE=C:\DOS\HIMEM.SYS
DEVICE=C:\DOS\EMM386.EXE NOEMS
If, after studying other memory requirements and memory use such as the
address space used by your video card (the program MSD, supplied with
MSDOS 6 can be used for this purpose), you decide that the memory area
D0000 to DFFFF may be used by Card Services, then change your lines as
shown below.
DEVICE=C:\DOS\HIMEM.SYS
DEVICE=C:\DOS\EMM386.EXE NOEMS /X=D000-DFFF
(Note that there is one 0 and one F missing from the memory address you enter
in CONFIG.SYS. This is because EMM386 expects a segment address. Each
segment contains 16 bytes, 0-15 (0-F), and so the beginning address in the
segment D000 is D0000 and the ending address of the segment DFFF is
DFFFF.)
Some graphics cards require memory to be excluded in the same way. More
than one region of memory may be excluded by repeated use of the /X=
option.
The EMMExclude line in SYSTEM.INI should reflect the EMM386 exclude
range. For example:
[386enh]
EMMExclude=D000-DFFF