MCC501RX166TD0B Motorola / Freescale Semiconductor, MCC501RX166TD0B Datasheet - Page 18

• Manufacturer Part Number: MCC501RX166TD0B
• Description: Network Processor, 16 Processing Elements, 166MHz Core Operating Frequency, 5Gbps Max Throughput, 838-CBGA
• Manufacturer: Motorola / Freescale Semiconductor

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January 21, 2002— Preliminary Version
Fabric Processor
Buffer Management
Unit
The Fabric Processor (FP) acts as a high-speed network interface port with advanced
functionality. It allows the C-5 NP to interface to an application-specific switching solution
internal to your design. The FP port supports the bidirectional transfer of packets, frames,
or cells from the C-5 NP to a hardware interface that provides connectivity to other
network processors or other similar line processing hardware. There are numerous
parameters that can be configured within the FP to allow the interface to be adapted to
different fabric protocols. The FP is Utopia-1, 2 and Utopia-3, IBM PRIZMA, and PowerX
(Csix-L0) compatible.
The FP can be configured to run at any frequency up to 110MHz, and the receive and
transmit data buses are 16 or 32 bits wide. This allows a wide range of supported
bandwidths to and from the switching fabric, all the way up to 3200Mbps full duplex
bandwidth.
The Buffer Management Unit (BMU) interfaces the C-5 NP to external pipeline
architecture, Single Data Rate Synchronous DRAM. The external memory is partitioned
and used as buffers for receiving and transmitting data between CPs, the FP, and the XP. It
is also used as second level storage in the XP memory hierarchy.
The interface to an array of SDRAM chips is 139bits wide, composed of 128 data bits, two
internal control bits, and nine SECDED (single error correction-double error detection) ECC
(error correction code) bits. The interface is compliant with the PC100 standard and
operates at up to 125MHz with 3.3V LVTTL-compatible inputs and outputs. The refresh
period, Trcd, Tcas, Trp, Tmrd, and Trc are configurable via boot time configuration (see the
C-5 Network Processor Architecture Guide for more details).
The C-5 NP uses auto-refresh mode and the interface, (which is not configurable),
transfers four bits of data for each read and write using a sequential burst type.
Some of these parameters are programmed into the SDRAMs’ mode register and can be
applied only once per power cycle. The ECC functionality can be enabled or disabled via
configuration register writes.
If needed, the interface can narrowed to 128bits by disabling ECC and providing board
pull-ups for the two control bits and nine ECC bits. This is useful if DIMMs are used in the
board design. If individual SDRAM parts are used, x16 and x32 are supported. The BMU
board logic is required to perform serial-to-parallel conversion for PROM address
outputs and parallel-to-serial conversion for PROM data inputs.
C-Port Confidential