InBoard 386, Adaptec Controller and Expanded Memory

• Microsoft Windows operating system versions 3.0, 3.0a

SUMMARY

You may have problems accessing expanded memory with Microsoft Windows version 3.0 on a system with an Intel InBoard 386 and Adaptec SCSI controller. This article describes the potential problems and provides some procedures to work around them.

MORE INFORMATION

Adaptec SCSI Controller

The Adaptec SCSI Controller has limited compatibility with Intel's InBoard 386. The ILIM386 (InBoard 386'S expanded memory software) swap parameter cannot be used because the Adaptec board has its own DMA controller that assumes the logical addresses equal the physical addresses. This is not true when swap is activated.

To work with ILIM386.SYS, load Adaptec's AH1544.SYS driver before ILIM386.SYS. The AH1540.SYS command line must contain the following parameters:

   /V386 /B=nnn   (where nnn = DMA buffer size)

Adaptec AT Hard Disk Controller

All Adaptec AT hard disk controllers use interrupts 60 to 67h and have a ROM address at C8000 to CBFFF or alternately at CC000 to CFFFF. These controllers conflict with expanded memory managers such as ILIM386.SYS, unless you install the driver ADAPTEC.SYS between the InBoard driver and ILIM386.SYS in the CONFIG.SYS file.

The Intel InBoard 386 provides up to three times faster performance than the 80286. It is compatible with the IBM PC/AT, IBM 3270 AT, COMPAQ DESKPRO 286(8MHz), COMPAQ PORTABLE 286, COMPAQ PORTABLE II, Tandy 3000HL, and Tandy 3000HD. It is expandable to 1MB with 256K chips and up to 3MB with Piggyback options. It supports the optional Intel 387 DX-16 math coprocessor.

The products included here are manufactured by vendors independent of Microsoft. We make no warranty, implied or otherwise, regarding these products' performance or reliability.