Intel 82555 manual LED Descriptions

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Networking Silicon — 82555

9.0LED Descriptions

The 82555 supports four LED pins to indicate link status, network activity and network speed.

•Link: This LED is off (logic high) until a valid link has been detected. After a valid link has been detected, the LED will remain on (active-low).

•Activity: This LED is on (active-low) when activity is detected on the wire. In DTE (adapter) mode, this LED is on during transmit and receive when the 82555 is not in loopback mode. In repeater mode, this LED is on only during receive when the 82555 is not in loopback mode.

•Speed: This LED will be on if a 100BASE-TX link is detected and off if a 10BASE-T link is detected. If the link fails while in Auto-Negotiation, this LED will keep the last valid link state. If 100BASE-TX link is forced this LED will be on, regardless of the link status. This LED will be of if the 10BASE-T link is forced, regardless of the link status.

•Full Duplex: The FDX_N signal can operate as a LED if it is enabled. It indicates full duplex link for either 100BASE-TX or 10 BASE-T technology.

MDI register 27 in Section 7.2.3.9, “Register 27: 82555 Special Control Bit Definitions” on page 34 details the information for LED function mapping and support enhancements.

Datasheet

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Contents 82555 10/100 Mbps LAN Physical Layer Interface Product FeaturesRevision Description Networking SiliconContents Repeater Mode Functional Overview IntroductionCompliance to Industry Standards Networking Silicon Architectural Overview 100 Mbps ModeMII TX Interface 10 Mbps ModeMedia Independent Interface MII Repeater mode only Transmit Error From RICYes Pin Numbers and Labels Pin DefinitionsPin Types Clock PinsTwisted Pair Ethernet TPE Pins Media Independent Interface MII PinsMedia Access Control/Repeater Interface Control Pins External Bias Pins LED PinsMiscellaneous Control Pins VCC Power and Ground PinsVSS 100BASE-TX Transmit Blocks 100BASE-TX Adapter Mode OperationSymbol 5B Symbol Code 4B Nibble Code 100BASE-TX Transmit Clock GenerationInvalid 2 100BASE-TX Scrambler and MLT-3 Encoder3 100BASE-TX Transmit Framing NRZ to MLT-3 Encoding DiagramTransmit Driver 100BASE-TX Receive BlocksVendor Model/Type 100BASE-TX Collision Detection Auto-Negotiation 100BASE-TX Link Integrity and Auto-Negotiation SolutionCombination Tx/T4 Auto-Negotiation Solution Link IntegrityAuto 10/100 Mbps Speed Selection Adapter Mode AddressesNetworking Silicon Datasheet 10BASE-T Receive Blocks 10BASE-T Functionality in Adapter Mode10BASE-T Transmit Clock Generation 10BASE-T Transmit Blocks10BASE-T Jabber Control Function 3 10BASE-T Error Detection and Reporting10BASE-T Collision Detection 10BASE-T Link Integrity10BASE-T Full Duplex Networking Silicon Datasheet Special Repeater Features Repeater ModeConnectivity Clock Signal Example MDI Frame Structure Management Data InterfaceTransition Bits Name Description DefaultMDI Registers MDI Registers 010BASE-T Register 1 Status Register Bit DefinitionsRegister 2 82555 Identifier Register Bit Definitions MDI Registers 16 MDI Registers 8100BASE-TX Register 17 82555 Special Control Bit Definitions150 Actled Liled Register 22 Receive Symbol Error Counter Bit DefinitionsPriority Technology Bit Setting TechnologyAuto-Negotiation Functionality DescriptionPriority Parallel Detect and Auto-NegotiationAuto-Negotiation and Parallel Detect Networking Silicon Datasheet LED Descriptions Networking Silicon Datasheet Scrambler Bypass Reset and Miscellaneous Test ModesReset LoopbackNumber Code Test Instruction Select Input to Tout Test Instruction CodingGeneral Operating Conditions Electrical Specifications and Timing ParametersDC Characteristics Absolute Maximum RatingsTotal supply current 230 Leakage on analog pins 11.3.3 100BASE-TX Voltage/Current DC CharacteristicsMII Clock Specifications AC CharacteristicsSymbol Parameter Conditions Min Typ Max Units MII Clocks AC Timing MII Timing ParametersRXC tri-stated a Repeater Mode Timing ParametersSquelch Test Timing Parameters Transmit Packet Timing ParametersReceive Packet Timing Parameters Jabber Timing ParametersAuto-Negotiation Fast Link Pulse FLP Timing Parameters 11.4.8 10BASE-T Normal Link Pulse NLP Timing Parameters11.4.11 X1 Clock Specifications Reset Timing ParametersX1 Clock Specifications 11.4.12 100BASE-TX Transmitter AC Specification12.0 82555 Package Information Symbol Description Min Norm Max10.0