Epson 20 - Manual (Page 112)

Using HDCACHE and EEMM386.EXE
The HDCACHE program (described in your MS-DOS Reference
Manual) cannot use expanded memory. If you use both HDCACHE
and EEMM386.EXE and you want HDCACHE to use extended
memory, you must not convert all your extended memory to
expanded memory with EEMM386.EXE. Instead, decide how much
extended memory you want to allocate to HDCACHE. Then use the
size parameter to convert the remainder of your extended memory to
expanded memory.
For example, if your computer has 2MB of memory, then it has 1MB
of extended memory. If you want to split this amount of memory
between EEMM386.EXE and HDCACHE, modify the DEVICE=
line to read:
DEVICE=EEMM386.EXE 512
512KB of your extended memory will be converted to expanded
memory by EEMM386.EXE. The remainder will be available to
HDCACHE.
5-34 Using
MS-DOS with Your
Equity 386