User Guide

ASUS PCI-SC875 User’s Manual 37
VI. WINDOWS 95
(SDMS )
VI. WINDOWS 95 DRIVERS
SDMS DRIVER SYMC8XX.MPD V2.02.00
Introduction for Windows 95
Windows 95 is an operating system designed to run on Intel processors using cur-
rent technology. It provides a graphical user interface environment incorporating
many high-level features (refer to the Microsoft Windows 95 documentation for
details). I/O requests in Windows 95 are handled by an I/O manager. To address a
SCSI peripheral, the I/O manager goes through the appropriate drivers. Class driv-
ers for hard disk, floptical, CD-ROM, printer, and scanner peripherals are provided
in Windows 95. Other class drivers, provided by peripheral manufacturers, are added
to support new devices. Symbios Logic/Microsoft provides a miniport driver, called
SYMC8XX.MPD, to complete the path to a Symbios Logic controller or processor
with an optional SDMS SCSI BIOS. The following sections describe this driver and
its installation.
Features
• Synchronous negotiation (including Fast/Ultra SCSI)
• Wide negotiation
• Auto Request Sense
• Supports multiple host adapters
• Supports multiple Logical Unit Numbers (LUNs)
• Disconnect/Reselect
• Scatter-Gather
• Differential Support
• Supports SCSI pass-through functionality
• BUS device reset
• Scan order change (scans the bus from SCSI ID 0 to MAX SCSI ID [7 or 15])
• Ultra SCSI (Fast 20) Support (20 MB/s narrow, 40 MB/s wide)
• SCAM Support (SCSI Configured AutoMatically)
Description
SYMC8XX.MPD is designed to Microsoft’s specification for miniport drivers. This
driver allows connection of SCSI devices including disk drives, CD-ROMs, and
tape drives for PCI-based machines. To support a new SCSI device the Windows 95
architecture requires that a class driver for that type device is present (usually sup-
plied by Microsoft, or possibly by the peripheral manufacturer). No changes to
SYMC8XX.MPD are required. This driver is only supported under Windows 95.
SCSI commands are passed directly from a Windows application to the SCSI de-
vices by using the SCSI pass-through facility (refer to the Microsoft Windows 95
documentation for details). This facility allows applications to directly control and
access SCSI devices by filling in a data structure and calling in to the port driver.
The SYMC8XX.MPD driver supports Ultra SCSI protocol, providing twice the raw
data transfer rate of Fast SCSI for disk drives and Symbios Logic host adapters that
support Ultra SCSI. However, Ultra SCSI requires more stringent SCSI bus cabling
setups than Fast SCSI.