User`s guide

IDE Controller
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Each controller has its own set of PCI configuration registers and SCSI I/O registers. As
a PCI 2.1 bus master, the SYM53C896 supports burst data transfers on PCI up to the
maximum rate of 132 MB per second using on-chip buffers.
Inthe internal bay, thesystem supportsup to sixone-inch SCSIharddisk drives, plus,in
the 5.25-inch removable media bays, three SCSI or IDE devices (the controller itself
supports more devices, but the 5.25-inch bay can contain a maximum of three devices).
A wide SCSI cable provides two connectors for Ultra SCSI devices (one of these
connectors is for the internal SCSI backplane). However, SCSI devices do not need to
operate at the ultra transfer rate. All drives on the bus must be Ultra-2 (LVD) to run at
80 MB/sec (40 MHz). The 5, 10, and 20 MHz operations can coexist on the bus and each
device will interact at its appropriate speed.
No logic, termination, or resistor loads are required to connect devices to the SCSI
controller other than termination in the device at the end of the cable. The SCSI bus is
terminated on the processor board with active terminators that can be disabled.
IDE Controller
IDE is a 16-bit interface for intelligent disk drives with AT disk controller electronics
onboard. The PCI/ISA/IDE Accelerator, called PIIX4E, is a multifunction device on the
processor board that acts as a PCI-based Fast IDE controller. The device controls:
• PIO and IDE DMA/bus master operations
• Mode 4 timings
• Transfer rates up to 22 MB/sec
• Buffering for PCI/IDE burst transfers
• Master/slave IDE mode
• Up to two drives for one IDE channel
Note: 18-inch maximum length of IDE cable on each channel: youcan connect an IDE
signalcable, up toa maximumof 18inches, tothe IDEconnector onthe processor board.
The cable can support two devices, one at the end of the cable and one six inches from
the end.