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Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
August 2006
Developer’s Manual
Reference Number: 306262-004US
51
Functional Overview—Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
2.1.2.4
APB Bus
The APB Bus is a 66.66-MHz, 32-bit bus that can be mastered by the AHB/APB bridge
only. The targets of the APB bus can be:
The APB interface is also used for NPE code download and configuration.
No arbitration is required due to a single master implementation.
2.1.3
MII/SMII Interfaces
The IXP45X/IXP46X network processors can be configured to support up to three MII or
SMII industry-standard, media-independent interface (MII) interfaces. These interfaces
are integrated into the IXP45X/IXP46X network processors with separate media-access
controllers and in many cases independent network processing engines.
The independent NPEs and MACs allow parallel processing of data traffic on the MII
interfaces and off-loading of processing required by the Intel XScale processor. The
IXP45X/IXP46X network processors are compliant with the IEEE 802.3 specification.
In addition to the MII interfaces, the IXP45X/IXP46X network processors include a
single management data interface that is used to configure and control PHY devices
that are connected to the MII interfaces. The IXP45X/IXP46X network processors
provide support for the serial media independent interface (SMII).
Note:
All the described NPE functions require Intel-supplied software executing on the NPEs.
For further information, see the Intel
®
IXP400 Software Programmer’s Guide. For
information on the availability of the NPE software and its enabling functions, contact
your local sales representative.
2.1.4
UTOPIA Level 2
The integrated UTOPIA Level 2 interface works with a network-processing engine for
several of the IXP45X/IXP46X network processors. The pins of the UTOPIA Level 2
interface are multiplexed with one of the MII/SMII interfaces.
The UTOPIA Level 2 interface supports a single- or a multiple-physical-interface
configuration with cell-level or octet-level handshaking. The network processing engine
handles segmentation and reassembly of ATM cells, CRC checking/generation, and
transfer of data to/from memory. This allows parallel processing of data traffic on the
UTOPIA Level 2 interface, off-loading processor overhead required by the Intel XScale
processor.
The IXP45X/IXP46X network processors are compliant with the ATM Forum’s UTOPIA
Level 2 Specification, Revision 1.0. The UTOPIA Level 2 interface of the IXP45X/IXP46X
network processors is an 8-bit interface.
• USB 1.1 device controller
• UARTs
• The internal bus performance
monitoring unit
• All NPEs
• GPIO
• Interrupt controller
• IEEE 1588 Hardware Assist
• Timers
• I
2
C
• Synchronous Serial Protocol
Interface