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Technical Information 1-13
PCI/IDE Ports
The system board provides two high-performance PCI/IDE ports: a primary channel and a
secondary channel. 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. The installed hard disk drive is connected to the primary PCI/IDE port. In
multimedia configurations, the installed CD-ROM reader is connected to the secondary
PCI/IDE port.
Parallel Interface
The system has a 25-pin parallel bidirectional enhanced 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 bidirectional transfer over a parallel
port. This increases parallel port functionality by supporting more devices.
The BIOS has automatic ISA printer port sensing. If the BIOS detects an ISA printer port
mapped to the same address, the built-in printer port is disabled. The BIOS also sets the
first parallel interface port it finds as LPT1 and the second port it finds as LPT2. The
interrupt is selected to either IRQ5 or IRQ7 via Setup. Software-selectable base addresses
are 3BCh, 378h, and 278h.
I/O addresses and interrupts for the parallel port are given in Table 1-6.
NOTE:
Any interrupts used for the built-in
parallel port are not available for ISA parallel
ports.
Table 1-6 Parallel Port Addressing and Interrupts
Starting I/O Address
Interrupt Level
Port
378
IRQ05
LPT1
278
IRQ05
LPT1 or LPT2
3BC
IRQ05
LPT1 or LPT2
378
IRQ07
LPT1
278
IRQ07
LPT1 or LPT2
3BC
IRQ07
LPT1 or LPT2
Parallel interface signals are output through the system board’s 25-pin, D-subconnector.
This connector is located at the rear of the system unit. Pin locations for the parallel
interface connector are given in Appendix A.
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