Nlx Design; Isa Bus; Pci Local Bus; Pci/Ide Ports - NEC POWERMATE 8100 Series Service And Reference Manual

NLX Design

The system is designed to conform to the NLX standard. Electrical and
mechanical interfaces and board dimensions are standardized.
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Signal and power connections to the system board are carried through the
riser board.
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The system board is free of internal cabling.
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A chassis latch releases and secures the system board for easy removal
and replacement.

ISA Bus

The system board uses the ISA bus for transferring data between the processor
and some I/O peripherals and expansion boards. The ISA bus supports 16-bit
data transfers and typically operates at 8 MHz.

PCI Local Bus

The 32-bit PCI local bus is the primary I/O bus for the system. The PCI bus is a
highly integrated I/O interface that offers the highest performance local bus
available for the Pentium processor. The bus supports burst modes that send
large amounts of data across the bus, allowing fast displays of high-resolution
images.
The PCI local bus is a high-performance bus that provides a processor-
independent data path between the CPU and high-speed peripherals. The PCI
bus is a robust interconnect mechanism designed specifically to accommodate
multiple high performance peripherals for graphics, full motion video, SCSI,
and LAN.
The PCI local bus supports memory transfer rates of over 100 MB per second
for reads and over 120 MB per second for writes, depending on processor
configuration.

PCI/IDE Ports

The system board supports two high-performance PCI/IDE ports: a primary port
and a secondary port (the port connectors are located on the riser board, which
plugs into the system board). Each port supports up to two devices for a total of
four IDE devices. The primary PCI/IDE port has an enhanced IDE interface that
supports PIO Mode 4 devices with 16 MB per second 32-bit wide data transfers
on the high-performance PCI local bus. Each port supports Ultra DMA/33.
The installed hard drive is connected to the primary PCI/IDE connector with a
three-connector cable. If a CD-ROM drive is included in the system, it is
connected to the secondary PCI/IDE port with a three-connector cable. A second
device can be added to the primary PCI/IDE port.
System Board 4-15