NEC Express5800/180Rb-7, User Manual

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System Overview 1-15
The SVGA controller supports analog VGA monitors (single and multiple frequency,
interlaced and noninterlaced) with a maximum vertical retrace noninterlaced frequency
of 100 Hz.
You can not add video memory to this system. Depending on the environment, the
controller displays up to 16.7 M colors in some video resolutions. It also provides
hardware-accelerated bit block transfers (BITBLT) of data.
SCSI Controller
A Symbios 53C896 Ultra2 SCSI chip provides two 16-bit high-speed SCSI channels.
This high-performance SCSI controller is capable of providing data rates up to 80
MB/sec per channel in 16-bit operations to ensure maximum data throughput while
minimizing PCI bus overhead.
Each channel is capable of operations using either 8- or 16-bit SCSI providing
10 MB/sec (Fast-10) or 20 MB/sec (Fast-20) throughput, or 20 MB/sec (Ultra),
40 MB/sec (Ultra-wide), or 80 MB/sec (40 MHz) (Ultra-2).
The SYM53C896 has its own set of PCI configuration registers and SCSI I/O registers.
As a PCI 2.1 bus master, the controller supports burst data transfers on PCI up to the
maximum rate of 132 MB/sec using on-chip buffers.
In the hot-swap SCSI hard drive bay, the system supports up to two 1-inch SCSI hard
disk drives. The 5.25-inch removable media bay supports one SCSI or IDE device (the
controller itself supports more devices, but the 5.25-inch bay can contain a maximum of
one device). 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 80MB/sec (40Mhz). 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 I/O carrier with active terminators.
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 I/O carrier that acts as a PCI-based Fast IDE controller. The device controls:
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PIO and IDE DMA/bus master operations
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Mode 4 timings
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Transfer rates up to 22 MB/sec (33 MB/sec using ultra DMA transfers)
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Buffering for PCI/IDE burst transfers
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Master/slave IDE mode