Alliance Semiconductor
2575 Augustine Drive ● Santa Clara, CA 95054 ● P: 408-855-4900 ● F: 408-855-4999 ● www.alsc.com
AS90L10204
January 2004
HyperTransport-to-PCI/PCI-X Bridge
Overview
The AS90L10204 is a high performance third generation
HyperTransport™-to-PCI/PCI-X bridge capable of tunneling the
data between the two HT ports or transferring the data between
the HT ports and the PCI/PCI-X port. It is designed for bandwidth-
hungry and performance-intensive applications in computer
servers, workstations, desktop PCs and embedded systems.
The AS90L10204 HT-to-PCI/PCI-X bridge expands the
possibilities of today’s systems architects by providing HT-based
design options never possible before. Each 8-bit HT port operates
at a frequency of up to 800 MHz DDR for both transmit and
receive directions and sustains a total aggregate bandwidth up to
25.6 Gbps per 8-bit bidirectional HT port. Each AS90L10204 HT
port can be 2, 4, or 8 bits wide in both transmit and receive
directions.
AS90L10204 supports one 64-bit, PCI/PCI-X1.0b port to
connect to a variety of PCI/PCI-X based peripherals and add-on
cards such as NICs, storage HBA and others. Up to 31 devices
can be daisy-chained to build higher capacity systems with
multiple PCI/PCI-X buses and HT-based peripherals
Key Features
Two bidirectional 8-bit HyperTransport interfaces:
• Supports 200, 400, 600 and 800 MHz DDR (double data rate)
for peak bandwidth of 3.2GB/s per 8-bit bidirectional HT port
• Supports dynamic frequency reprogramming
Complies with HyperTransport 1.05 Interface Specification.
Tunnels between the two HyperTransport interfaces.
No protocol-induced maximum HyperTransport link length, which
allows system designers to optimize speed vs. distance.
The HT interfaces support dual-hosted chain (host CPU on each
port) with the capability to transfer data from the PCI/PCI-X bus
to either host CPU.
1 x 64 bit, up to 133MHz PCI-X 1.0b with support for up to
66MHz PCI 2.2
Complies with PCI Local Bus Specifications, Rev. 2.2
Supports with parity and error checking features.
Built-in two-level PCI arbiter with support for up to six devices
• Can also be configured to support an external arbiter.
3.3 V PCI I/O with 5 V tolerant I/Os.
Transaction forwarding for the following commands:
• All I/O and memory commands
• Type 1 to Type 1 configuration commands (downstream only)
• Type 1 to Type 0 configuration commands (downstream only)
Evaluation board available with firmware and software drivers.
1.8 V core, 1.2 V HT IO, 3.3 V PCI/PCI-X IO.
JTAG port.
Device Block Diagram
Press Release
64-bit PCI/PCI-X Port
•1x 64-bit, 66MHz PCI or 133MHz PCI-X 1.0b
Rx
PHY
Tx
PHY
Rx
FIFO
Link Interface
Rx Buffer
Tx
FIFO
Link Interface
Packet Generator
Rx
PHY
Tx
PHY
Rx
FIFO
Link Interface
Rx Buffer
Tx
FIFO
Link Interface
Packet Generator
PCI/PCI-X Interface
HT1.05 Interface HT1.05 Interface
8-bit HT
@ 800MHz
8-bit HT
@ 800MHz
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2003, 2004 © Copyright Alliance Semiconductor Corporation. All Rights reserved.
January 2004 AS90L10204 Product Brief
Summary of Benefits Target Applications
• Bridges between HyperTransport and PCI/PCI-X bus to
tap into the vast infrastructure of PCI/PCI-X based add-
on NIC Storage HBA and others
• 3.2 GB/sec bandwidth supports the needs of data
transfer applications.
• Host CPUs can be connected to both HT interfaces for
greater system flexibility and for sharing PCI/PCI-X
based resources.
• Supports PCI Plug and Play capability reducing system
design complexity and time to market.
• Low power consumption increases system reliability.
• Built-in PCI/PCI-X arbiter reduces system cost.
• Uses existing PCI/PCI-X drivers and firmware to
reduce system development and debug time.
• 31 devices can be daisy-chained to enable a flexible
and modular system implementation.
• Deterministic low latency per tunnel meets the
requirements of real-time applications.
The feature set of the AS90L10204 makes it ideal for a
variety of computing and embedded systems including:
• High-end computing systems
• Computer Servers
• Server clusters
• Workstations
• Desktop PCs
• Storage systems and switches (SAN, NAS, RAID, FC)
• Printing, graphics, and imaging Systems
• VPN switches and routers
• Edge and access routers
• Wireless gateways
• Voice and multimedia access gateways
• IP service switches and core routers
• Test equipment and network probes
• Embedded systems
System Block Diagram
Contact Us
Alliance Semiconductor Corporation
2575 Augustine Drive
Santa Clara, CA, 95054, USA
Phone: 408-855-4900, Fax: 408-855-4999
www.alsc.com
Notice:
Information in this document is subject to change without notice
HyperTransport™ is a trademark of the HyperTransport
Technology Consortium
Memory
Graphics
Controller
HT
Port
HT
Port
PCI/PCI-X
AS90L10204
North
Bridge
HT
Port
AGP
CPU
Core
I/O peripherals
PCI/PCI-X Peripheral
South
Bridge
