IBM 25CPC710 ユーザーズマニュアル

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Version 1.0 
11/08/01 
 
 
 
 
 
 
 
Abstract 
This Application Note describes the differences between the CPC710-100+ (DD2) and the 
CPC710 (DD3.x) versions of the PowerPC Dual PCI/Memory Controller companion chip. The 
purpose of this note is to provide designers with an overview of the changes and point out 
performance enhancements and potential programming changes. For a detailed 
understanding of the operation of the CPC710-133, please refer to the User’s Manual. For a 
detailed understanding of the physical pin out and electrical specifications, please refer to the 
Data Sheet. 
 
Overview 
 
The IBM25CPC710 DD3.x is a host bridge that interfaces a PowerPC 60x bus with system 
memory (SDRAM) and two independent PCI interfaces. It provides arbitration for one to
 
four 
processors and supports up to two levels of pipelining per processor with 64-byte buffers 
(maximum of 6 buffers). Use of external slave devices on the 60x bus is also supported and 
requires additional external logic. The CPC710 DD3.x supports 60x bus speeds of up to 133MHz 
at 2.5V.
 
Of course, given signal quality issues with higher bus speeds it is not recommended that 
the CPU bus run at 133Mhz in configurations that include more than 2 CPUs. 
 
 
The bridge’s two way interleaved memory controller supports SDRAM at 100 or 133 MHz; 
both single bank and dual bank, PC100, PC133 and registered DIMMs are supported. The 
memory controller design requires the use of an external multiplexer and two physical DIMMs. 
 
 
The bridge contains two PCI host bus bridges: one provides an interface for a 32-bit, 33 MHz 
PCI bus for standard and native I/O. This bus supports either 3.3V or 5V logic level devices, and 
allows attachment of up to 2MB of boot ROM (and up to 256MB of extended boot ROM).  The 
other PCI interface supports a 32- or 64-bit, 33 or 66 MHz PCI bus for high data throughput, but 
supports only 3.3V logic level devices. This is a change from the previous revision
.
 Burst and 
non-burst data transfers to memory from the PCI (bridge acts as target on PCI bus) and from 
memory to the PCI  (bridge acts as master on PCI bus) are supported; data transfers directly 
between PCI-32 and PCI-64 are not supported
This is a change from the previous revision. 
 
 
A single channel DMA controller provides support for large data transfers between 
memory and the PCI busses. DMA to and from the CPU bus to memory, or between PCI-32 and 
PCI-64 is not supported.
 
This is a change from the previous revision. 
IBM25CPC710 Bridge Chip: 
Enhancements and Changes in the 
DD3.x revisions
 
November 8, 2001 
 
Version 1.0 
PowerPC
TM
 Applications 
IBM Microelectronics 
Research Triangle Park, NC 
ppcsupp@us.ibm.com
 
http://www.chips.ibm.com