24888 Rev 3.03 - July 12, 2004 AMD-8151
TM
AGP Tunnel Data Sheet
1
Cover page
AMD-8151
TM
HyperTransport
TM
AGP3.0 Graphics Tunnel
Data Sheet
1Overview
The AMD-8151
TM
HyperTransport
TM
AGP3.0 Graphics Tunnel (referred to as the IC in this document) is a
HyperTransport™ technology (referred to as link in this document) tunnel developed by AMD that provides an
AGP 3.0 compliant (8x transfer rate) bridge.
1.1 Device Features
• HyperTransport technology tunnel with side A
and side B.
• Side A is 16 bits (input and output); side B is
8 bits.
• Either side may connect to the host or to a
downstream HyperTransport technology
compliant device.
• Each side supports HyperTransport technol-
ogy-defined reduced bit widths: 8-bit, 4-bit,
and 2-bit.
• Side A supports transfer rates of 1600, 1200,
800, and 400 mega-transfers per second.
Side B supports transfer rates of 800 and
400 mega-transfers per second.
• Maximum bandwidth is 6.4 gigabytes per
second across side A (half upstream and half
downstream) and 1.6 gigabytes per second
across side B.
• Independent transfer rate and bit width
selection for each side.
• Link disconnect protocol supported.
• AGP 8x bridge.
• Compliance with AGP 3.0 specification sig-
naling, supporting 4x and 8x transfer rates.
• Compliance with AGP 2.0 specification 1.5-
volt signaling, supporting 1x, 2x, and 4x
data-transfer modes.
• Supports up to 32 outstanding requests.
• 31 x 31 millimeter, 564-ball BGA package.
• 1.5 volt AGP signaling; some 3.3 volt IO; 1.2
volt link signaling; 1.8 volt core.
Figure 1: System block diagram.
AMD-8151
TM
Device
Host
HyperTransport
TM
Link
16 bits upstream,
16 bits downstream
HyperTransport
Link
8 bits upstream,
8 bits downstream
Downstream
Device
tunnel
Side A Side B
AGP
Bridge
AGP Graphics
Controller
