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P5F97/P5F103 User’s Manual
1.9 Enhanced IDE Support
The P5F97/P5F103 mainboard provides two enhanced high performance
PCI IDE interfaces capable of supporting four devices with PIO mode 0
through mode 4, bus-mastering DMA mode 2, and bus-mastering Ultra
DMA/33 ATAPI devices. Detection of IDE device type and transfer rate
is automatically performed by the BIOS. The traditional PIO IDE device
requires a substantial amount of CPU bandwidth to handle all the
activities of IDE access including waiting for mechanical activities. The
Bus Master logic designed in the ALi Aladdin V chipset is intended to
reduce the workload of the CPU, hence increasing CPU efficiency. The
Bus Master takes care of the data transfer between IDE and memory,
and lets the CPU handle other tasks. In true multi-tasking operating
systems such as Windows 95, Windows98, Windows NT, and OS/2, by
using bus-mastering IDE, the CPU workload can be reduced to complete
other tasks while disk data transfers are occurring. The driver must be
loaded in order to make the EIDE drive operate in bus-mastering DMA
mode.
The following is a data transfer rate comparison table for different IDE
operating modes
:
1.10 Keyboard, Mouse and USB Interface
The 5V line to the PS/2 keyboard, mouse connector and USB header, are
protected with 3Amp/125V fuse.
The P5F97/P5F103 mainboard has a dual USB connector to support
two USB ports. The USB is a serial bus interface standard that is
Operating Mode
Maximum Data Transfer Rate
PIO Mode 3
11.1 MB/Second
PIO Mode 4
16.6 MB/Second
DMA Mode 1
13.3 MB/Second
DMA Mode 2
16.6 MB/Second
Ultra DMA/33
33.2MB/Second
Chapter 1: Introduction
