Pci/Ide Ports; Parallel Interface - NEC POWERMATE ENTERPRISE NETPC Service Manual

1-16 Technical Information

PCI/IDE Ports

The system board supports one high-performance PCI/IDE port (the primary channel for a
master/slave configuration), though the port is actually located on the riser card. The port
supports one or two devices in a master/slave setting configurable in BIOS Setup. 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.
The channel supports Ultra DMA/33. The installed hard disk drive is connected to the
primary PCI/IDE port with a two-connector cable. A second Ultra DMA/33 device can be
logically added to the primary PCI/IDE channel, but in such a case, neither device should
run in Ultra DMA/33 mode because the length of the three-connector cable required for this
configuration would cause signal degradation.

Parallel Interface

The system has a 25-pin bi-directional parallel port on the system board. Port specifications
conform to the IBM-PC standards. The port supports Enhanced Capabilities Port (ECP)
and Enhanced Parallel Port (EPP) modes for devices that require ECP or EPP protocols.
The protocols allow high-speed bi-directional transfer over a parallel port and increase
parallel port functionality by supporting more devices.
The BIOS has automatic ISA printer port sensing that works with most devices. If the
BIOS detects an ISA printer port mapped to the same address, the built-in printer port is
disabled. (Verify in the BIOS Setup that printer ports mapped to the same address are
enabled or disabled appropriately.) The BIOS also sets the first parallel interface port it
finds as LPT1 and the second port it finds as LPT2. The interrupt is set at IRQ7 via the
Setup utility. Software-selectable base addresses are 3BCh, 378h, and 278h.
Sets of I/O addresses and interrupts for the parallel port are given in Table 1-8. This is a list
of all possible configurations; the parallel port uses only one set.
Table 1-8 Parallel Port Addresses and Interrupts
Starting I/O Address
378
278
228
378
278
228
NOTE: Physically, the chassis only has room for
one hard disk drive.
Interrupt Level
IRQ05
IRQ05
IRQ05
IRQ07
IRQ07
IRQ07
Port
LPT1
LPT2
LPT3
LPT1
LPT2
LPT3