NXP Semiconductors
AN10050
Designing a Hi-Speed USB host PCI adapter using ISP1562/63
AN10050_4
© NXP B.V. 2007. All rights reserved.
Application note
Rev. 04 — 1 November 2007
3 of 18
1. Introduction
The ISP1562 and the ISP1563 are Hi-Speed Universal Serial Bus (USB) host controllers
(HCs) that can be directly connected to a standard 32-bit, 33 MHz PCI bus. For the rest
of this document, they will be known as ‘ISP1562/3’. The ISP1562/3 complies with
PCI
Local Bus Specification Rev. 2.2
and
PCI Bus Power Management Interface
Specification Rev. 1.1
. No additional logic is required to implement a complete Hi-Speed
USB host controller solution on Peripheral Component Interconnect (PCI).
Adapter cards based on the ISP1562/3 implement three functions: function 0 and
function 1 for OHCI1 and OHCI2, and function 2 for EHCI. According to
PCI Local Bus
Specification
, each physical PCI device may incorporate one to eight separate functions
(logical devices). Each function contains its own memory-mapped individually
addressable configuration space of 256 bytes, containing configuration registers.
The configuration registers of the ISP1562/3 are used by the system’s BIOS and the
operating system to detect the presence of the respective functions, that is, Vendor ID
(VID) and Product ID (PID), to determine the necessary resource requirements, that is,
memory and I/O space, interrupt lines, and so on, and for specific capabilities.
A set of on-chip ‘operational’ registers is also defined for each of the three host
controllers implemented in the ISP1562/3. The respective host controller device driver
interacts with these registers to implement the USB functionality and the legacy support.
A detailed description of configuration registers and operational registers can be found in
the ISP1562 and ISP1563 data sheets.
The ISP1562/3 implements two internal ‘power wells’, V
DD
and V
DDX
, to benefit from the
PCI V
AUX
= 3.3 V dedicated power source, which is present on the PCI connector (pin
A14) even when PCI V
CC
= 3.3 V is off. This enables the ISP1562/3 PME# signal to be
asserted and activates the wake-up logic of the motherboard, even if the rest of the
system is powered down; for example, in S3
cold
system standby mode. This is applicable
mainly to onboard (desktop) or mobile designs, but not applicable to PCI add-on cards
because the PCI +5 V, used for V
BUS
, is also off during S3
cold
.
The ISP1562/3 may use PCI V
AUX
to power its four internal transceivers connected to the
ISP1562/3 V
DDA_AUX
(analog), and also the clock circuitry, port router, root hub and Power
Management Event (PME#) logic connected to the ISP1562/3
V
CC(I/O)_AUX
(digital).
For details on implementation of the PCB design, see
Section 4
.
The power management capabilities enabled by using PCI V
AUX
allow system designers
to meet the governmental energy regulations that are becoming increasingly essential
worldwide: Energy Star/USA: 30 W standby, White Swan/Europe: 5 W standby, Blue
Angel/Europe: 5 W standby.
This document provides a description of the application schematics and the PCB design
recommendations.
2. ISP1562/3
initialization
The following sequence is required during the ISP1562/3 initialization, for correct
functionality:
1. Register HcRhDescriptorA = 902h. This means that bit PSM = 1b.
2. Register HcControl = 680h. This means that bits HCFS[1:0] = 10b (operational
mode).
