[comp.sys.ibm.pc] Need Ext Memory Prog Help/Advice!

cjl@ecsvax.UUCP (Charles Lord) (08/05/87)

I am working with an AT-based data acquisition system and
have a real problem brewing.  I will need to store ~2Mb of
data in real time as fast as I can store it, and that's where
the real fun begins.  I have a generic Taiwan 2.5Mb extended
memory card in the system that I wish to write to directly
but cannot find decent documentation as to any quick way to
get into protected mode, make the transfer, and return without
a lot of processing overhead.  

I am familiar with INT 15 Function 88 to transfer blocks back
and forth such as VDISK does, but that routine takes around
300 ms to transfer 64K and I need to write the data to the
extra memory as I get it.  After the event is over I can take my
own sweet time getting the data back to the base 640K for
storage/manipulation.

Any ideas/suggestions/references? PLEASE don't suggest using another
uP such as the 68000 as that is rubbing salt in painful wounds.
The 80x86 family may be nice to program for multiprocessing,
but it stinks for straightforward large memory model processes.
(flame off)

Any suggestions / help greatly appreciated!

Charles Lord
cjl@ecsvax.UUCP (CCCP?)
...!decvax!mcnc!ecsvax!cjl