Freescale Semiconductor MPC8260 - Manual (Page 117)

Overview
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 1-23
to store ATM connection tables. Therefore, an external PCI bridge is necessary. In systems with fewer than
128 active connections or where the ATM average bit rate is lower that 155 Mbps, the local bus may not
be necessary to store connection tables, and it may be possible to use it as PCI bus.
1.7.2.6 PowerQUICC II as PCI Agent
Figure 1-14 shows the configuration when the PowerQUICC II acts as the PCI agent (refer to note at the
beginning of Section 1.7, “Application Examples.” ).
Figure 1-14. PowerQUICC II as PCI Agent
In this system, the PowerQUICC II is a PCI agent on an I/O card and the PCI host resides on the PCI bus.
An external PCI bridge is used to connect the host to the PCI bus. The internal PCI bridge in the
PowerQUICC II is used to bridge between the PCI bus and the 60x bus on the PowerQUICC II.
PCI Bus
60x Bus
SDRAM/SRAM/DRAM
ATM Connection Tables
and/or
PowerQUICC II
Communication
Channels
UTOPIA
PHY
ATM
PHY
PCI Bridge
System Bus
Host
Processor
Agent
Host
Memory
Communication Data