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Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
August 2006
Developer’s Manual
Order Number: 306262-004US
23
Contents—Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
20.5.3.4 Transmit FIFO Service Request Flag (TFS)
(Read-Only, Maskable Interrupt)............................................... 870
20.5.3.5 Receive FIFO Service Request Flag (RFS)
(Read-Only, Maskable Interrupt)............................................... 870
20.5.3.6 Receiver Overrun Status (ROR) ................................................ 870
20.5.3.7 Transmit FIFO Level (TFL)........................................................ 871
20.5.3.8 Receive FIFO Level (RFL) ......................................................... 871
21.0 I2C Bus Interface Unit ........................................................................................... 875
21.1 Overview ....................................................................................................... 875
21.2 Feature List .................................................................................................... 875
21.3 Block Diagram ................................................................................................ 875
21.4 Theory of Operation......................................................................................... 876
21.4.1 Operational Blocks................................................................................ 877
21.4.2 I
C Bus Interface Modes........................................................................ 878
21.4.3.1 START Condition..................................................................... 880
21.4.3.2 No START or STOP Condition .................................................... 880
21.4.3.3 STOP Condition ...................................................................... 881
C Bus Operation ........................................................................................... 881
21.5.1 Serial Clock Line (SCL) Generation.......................................................... 881
21.5.2 Data and Addressing Management.......................................................... 882
21.5.2.1 Addressing a Slave Device ....................................................... 882
C Acknowledge.................................................................................. 883
21.5.4.1 SCL Arbitration ....................................................................... 884
21.5.4.2 SDA Arbitration ...................................................................... 885
21.5.5 Master Operations ................................................................................ 886
21.5.6 Slave Operations.................................................................................. 889
21.5.7 General Call Address............................................................................. 891
21.6.1 Initialize Unit ....................................................................................... 892
21.6.2 Write n Bytes as a Slave ....................................................................... 892
21.6.3 Read n Bytes as a Slave ........................................................................ 893
21.7.1 Initialize Unit ....................................................................................... 894
21.7.2 Write 1 Byte as a Master ....................................................................... 894
21.7.3 Read 1 Byte as a Master........................................................................ 894
21.7.4 Write 2 Bytes and Repeated Start Read 1 Byte as a Master ........................ 895
21.7.5 Read 2 Bytes as a Master — Send STOP Using the Abort............................ 895
C Control Register - ICR ..................................................................... 897
C Status Register - ISR....................................................................... 899
C Slave Address Register - ISAR .......................................................... 901
C Data Buffer Register - IDBR ............................................................. 902
C Bus Monitor Register - IBMR............................................................. 902
22.0 Public Key Exchange Crypto Engine ....................................................................... 905
23.0 AHB-PKE Bridge ..................................................................................................... 907
23.1 Overview ....................................................................................................... 907
23.2 Feature List .................................................................................................... 907
23.3 Block Diagram ................................................................................................ 908