Compaq AlphaPC 264DP Technical Reference Manual page 51

This chapter describes the functional operation of the AlphaPC 264DP. It introduces
the 21272 core logic chipset (21272) and describes its implementation with the
21264 microprocessors and their supporting memory and I/O devices.
Information, such as bus timing and protocol, found in other specifications, data
sheets, and reference documentation is not duplicated here.
For detailed descriptions of chipset logic, operations, and transactions,
Note :
refer to the 21272 chips' specification. For details of the PCI interface,
refer to the PCI System Design Guide and the PCI Local Bus Specifica-
tion.
4.1 21272 Core Logic Chipset Introduction
The 21272 provides a solution for designers developing uniprocessor or dual-pro-
cessor systems using the 21264 microprocessor. The chipset provides a 256-bit
memory interface and includes the following three gate arrays:
•
Cchip: Address and commands, 432-pin ESBGA
•
Dchip: Data path, 304-pin ESBGA
•
Pchip: PCI interface, 304-pin ESBGA
12 February 1999 – Subject To Change
21272 Core Logic Chipset Introduction
Functional Description
Functional Description
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4–1