24888 Rev 3.03 - July 12, 2004

AMD-8151TMAGP Tunnel Data Sheet

AGP Most Recent Request Register

DevA:0x60

 

 

As each PIPE mode or SBA mode AGP request is transferred into the IC, the fields are placed into this register. Thus, this register provides the fields of the most recent AGP requests. Any sticky bits from prior requests that have not been updated in the current request are also valid. Note: fences are not captured by this register.

Default: 0000 0000 0000 0000h

Attribute: Read only.

Bits

Description

 

 

 

 

63:44

Reserved.

 

 

 

43:40

MRC: most recent command field. Specifies the command field of the most recent AGP request.

 

0h=LP (low priority) read. 1h=HP (high priority) read. 4h=LP write. 5h=HP write. 8h=LP long read.

 

9h=HP long read. Ah=Flush.

 

 

 

39:3

MRA: most recent address. Specifies address bits[39:3] of the most recent AGP request.

 

 

2:0

MRL: most recent length field. Specifies the length field of the most recent AGP request.

 

 

 

AGP Revision and Capability Register

DevA:0xA0

 

 

 

Default: 0030 C002h

Attribute: Read only.

Bits

Description

 

 

 

 

31:24

Reserved.

 

 

 

23:16

AGP specification. This field is hardwired to indicate that the IC conforms to AGP specification

 

revision 3.

 

 

 

15:8

Next capabilities block. Specifies the offset to the next capabilities block.

 

 

7:0

Capabilities type. Specifies the AGP capabilities block.

 

 

 

AGP Status Register

DevA:0xA4

 

 

 

Default: 1F00 0B2?h (see bit descriptions for bits[3:0])Attribute: Read only.

Bits

Description

 

 

31:24

RQ: maximum number of outstanding requests. This field is set to indicate support for 32

 

outstanding requests.

 

 

23:18

Reserved.

 

 

17

Isochronous support. This bit fixed in the low state to indicate that the IC does not support

 

isochronous modes.

 

 

16:13

Reserved.

 

 

12:10

Calibration cycle. This field is set to indicate a requirement for calibration cycles every 64 millisec-

 

onds.

 

 

9

SBA support. This field is set to indicate support for SBA.

 

 

8

Coherency. This bit fixed high.

 

 

7

64-bit GART support. This bit fixed low.

 

 

6

Host translation#. This bit fixed low.

 

 

5

Greater-than 4 gigabyte support. This bit fixed high.

 

 

 

 

 

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AMD 8151 specifications AGP Revision and Capability Register, AGP Status Register, Bit Gart support. This bit fixed low

8151 specifications

The AMD 8151 is a notable member of AMD's family of chipsets, designed to complement the AMD K5 and K6 processors. Released in the late 1990s, this chipset was primarily targeted at performance-driven PCs. The AMD 8151 provided users with an array of features and technologies that enhanced the overall computing experience, making it a popular choice among system builders and enthusiasts at the time.

One of the standout features of the AMD 8151 is its support for a 64-bit data bus. This significant design choice allowed for faster data transfer rates and better communication between the CPU and other critical components, such as memory. The chipset was capable of supporting multiple memory configurations, including ECC (Error-Correcting Code) memory, which enhanced system reliability, particularly for servers and workstations.

In terms of connectivity, the AMD 8151 included several integrated controllers, such as the PCI controller, which facilitated connections to various peripherals and expansion cards. With its support for the PCI bus, users could take advantage of high-speed devices, such as graphics cards, sound cards, and network adapters, enhancing the overall functionality of their systems.

Another important characteristic of the AMD 8151 is its power management capabilities. The chipset featured advanced power management technologies, which allowed systems to use energy more efficiently. This not only helped reduce operational costs but also contributed to less heat production, extending the longevity of the components within the PC.

The AMD 8151 also offered robust support for a range of bus speeds, which provided flexibility for users looking to customize their systems. With a maximum bus speed of 66 MHz, it was well-suited for the processors of its time, ensuring compatibility and optimal performance.

Moreover, the AMD 8151 played a crucial role in the development of 3D graphics capabilities. It was designed to work seamlessly with AMD's 3D graphics technology, which allowed for improved visual performance in gaming and multimedia applications. This made it an appealing choice for users who prioritized graphics performance.

Overall, the AMD 8151 chipset embodied the technological advancements of its era, providing enhanced performance, flexibility, and reliability. It stood as a testament to AMD's commitment to innovation in the computing space, marking a significant chapter in the evolution of PC architecture.