Motorola MPC8260 - Manual (Page 82)

1-12 MPC8260 PowerQUICC II UserÕs Manual MOTOROLA
Part I. Overview
In this application, eight TDM ports are connected to external framers. In the MPC8260,
each group of four ports support up to 128 channels. One TDM interface can support 32Ð
128 channels. The MPC8260 receives and transmits data in transparent or HDLC mode,
and stores or retrieves the channelized data from memory. The data can be stored either in
memory residing on the 60x bus or in memory residing on the local bus.
The main trunk can be conÞgured as 155 Mbps full-duplex ATM, using the UTOPIA
interface, or as 10/100 BaseT Fast Ethernet with MII interface, or as a high-speed serial
channel (up to 45 Mbps). In ATM mode, there may be a need to store connection tables in
external memory on the local bus; for example, 128 active internal connections require 8
Kbytes of dual-port RAM. The need for local bus depends on the total throughput of the
system. The MPC8260 supports automatic (without software intervention) cross connect
between ATM and MCC, routing ATM AAL1 frames to MCC slots.
The local bus can be used as an interface to a bank of DSPs that can run code that performs
analog modem signal modulation. Data to and from the DSPs can be transferred through
the parallel bus with the internal virtual IDMA.
The MPC8260 memory controller supports many types of memories, including EDO
DRAM and page-mode, pipeline SDRAM for efÞcient burst transfers.
1.7.1.2 Regional OfÞce Router
Figure 1-4 shows a regional ofÞce router conÞguration.
Figure 1-4. Regional Office Router Configuration
Quad
T1
Framer
MII
Transceiver
MPC8260
TDM0
TDM3
10/100BaseT 60x Bus
SDRAM/DRAM/SRAM
Channelized Data
(up to 128 channels)
10/100BaseT
SMC/I 2 C/SPI/SCC
Slow
Comm
PHY