Compaq iPAQ 1.0 User Manual

Chapter 5 Input/Output Interfaces
5-22 Compaq iPAQ Series of Desktop Personal Computers
Second Edition – February 2001
5.7 UNIVERSAL SERIAL BUS INTERFACE
The Universal Serial Bus (USB) interface provides USB 1.1-compliant asynchronous/isochronous
data transfers of up to 12 Mb/s. This high-speed interface supports hot-plugging of compatible
devices, making possible system configuration changes without powering down or even rebooting
systems. The USB uses a tiered scheme for connecting multiple devices. A USB device may be
connected directly to the computer’s USB port or daisy-chained off another USB device connected
to the computer. Up to 127 USB devices may be connected (tiered) to the host (computer).
NOTE: It is recommended to run the Windows 98 (or later) operating system when using
USB peripherals, especially a USB keyboard and USB mouse. Problems may be
encountered when using USB devices with a system running Windows 95, although some
peripherals may operate satisfactorily.
As shown in Figure 5-8, USB interfacing is provided by the 82801 ICH or ICH2 component and a
TPS2054 or TUS2046B hub component.
Figure 5-8. USB I/F, Block Diagram
Legacy-free iPAQ 1.0/1.2 and all iPAQ 2.0 systems provide both direct-controller and through-hub
USB connections for USB peripherals. For maximum efficiency, direct-controller ports should be
reserved for connection with a high-data throughput device such as a digital camera or CD. On
iPAQ 2.0 systems, USB port 0 (upper left as viewed from rear) is a dedicated-direct port that
assures full speed operation with a USB device. Through-hub ports can efficiently handle multiple
(daisy-chained) devices such as a keyboard and mouse that require only intermittent or low
capacity data.
USB
Hub
USB
Data 1
82801
ICH
USB
Cntlr.
Rear Panel
USB Port 0
USB Port 1
USB Port 2
USB Port 3
Front Panel
USB Port 4
USB
Data 0
USB
Data 1
82801
ICH2
USB
Cntlr. A
USB Data 0
Front Panel J110
USB Port 4
USB Port 5
USB Port 6
USB
Cntlr. B
USB
Hub
USB
Data 3
NC
USB Data 2
Rear Panel J111
USB Port 1
USB Port 0
IPAQ 2.0 SystemIPAQ 1.0/1.2 System
Rear Panel J112
USB Port 3
USB Port 2
Legacy-free systems only Not connected Direct port

Compaq iPAQ 1.0 Specifications

General

Brand	Compaq
Model	iPAQ 1.0
Category	Desktop
Language	English