`Std 802.3, 1998 Edition
`
`LOCAL AND METROPOLITAN AREA NETWORKS:
`
`Value of speed selection bit for
`single speed PHY
`
`Single speed PHY ignores
`writes to speed selection bit
`
`Auto-Negotiation enable
`
`Duplex mode, speed selection
`have no effect when Auto-Ne-
`gotiation is enabled
`
`PHY without Auto-Negotiation
`returns value of zero
`
`PHY without Auto-Negotiation
`ignores writes to enable bit
`
`Response to management
`transactions in power down
`
`Spurious signals in power
`down
`
`TX_CLK and RX_CLK stabi-
`lize within 0.5 s
`
`PHY Response to input signals
`while isolated
`
`High impedance on PHY out-
`put signals while isolated
`
`Response to management
`transactions while isolated
`
`Default value of isolate
`
`PHY without Auto-Negotiation
`returns value of zero
`
`PHY without Auto-Negotiation
`ignores writes to restart bit
`
`Restart Auto-Negotiation
`
`Return 1 until Auto-Negotia-
`tion initiated
`
`Auto-Negotiation not effected
`by clearing bit
`
`Value of duplex mode bit for
`PHYs with one duplex mode
`
`PHY with one duplex mode ig-
`nores writes to duplex bit
`
`Loopback not affected by du-
`plex mode
`
`Assertion of COL in collision
`test mode
`
`Subclause
`
`22.2.4.l.3
`
`22.2.4.1.3
`
`22.2.4.1.4
`
`22.2.4.l.4
`
`22.2.4.l.4
`
`22.2.4.1.4
`
`22.2.4.1.5
`
`22.2.4.1.5
`
`22.2.4.l.5
`
`22.2.4.1.6
`
`22.2.4.l.6
`
`22.2.4.1.6
`
`22.2.4.1.6
`
`22.2.4.l.7
`
`22.2.4.l.7
`
`22.2.4.1.7
`
`22.2.4.l.7
`
`22.2.4.l.7
`
`22.2.4.1.8
`
`22.2.4.1.8
`
`22.2.4.1.8
`
`22.2.4.1.9
`
`Value/Comment
`
`Set to match the correct PHY
`speed
`
`By setting 0.12 = 1
`
`If0.12=1, bits 0.13 and 0.8
`have no effect on link configu-
`ration
`
`Yes (if 1.3=o, then 0.12:0)
`
`Yes (if 1.3=0, 0.12 always = 0
`and cannot be changed)
`
`Remains active
`
`None (not allowed)
`
`Yes (after both bits 0.11 and
`0.10 are cleared to zero)
`
`NONE
`
`Yes (TX_CLK, RX_CLK,
`RX_DV, RX_ER, RXD<3:0>,
`COL, and CRS)
`
`Remains active
`
`0.l0=1
`
`0.9=0if1.3=0or0.12=0
`
`0.9 = 0, cannot be changed if
`1.3 = 0 or0.12 =0
`
`When 0.9= 1 if0.l2 = 1 and
`l.3=l
`
`0.9 is self clearing to 0
`
`Set 0.8 to match the correct
`PHY duplex mode
`
`Yes (0.8 remains unchanged)
`
`Yes (0.8 has no effect on PHY
`when 0.14 = 1)
`
`Within 512 BT after TX_EN is
`asserted
`
`This is anygtrchive IEEE Standard.
`
`It has been superseded byogplgggrg/g§§iggEg(..tI{g§s$;agag@rd.
`
`Aerohive - Exhibit 1025
`
`0092
`
`Aerohive - Exhibit 1025
`0092
`
`
`
`CSMA/CD
`
`De-assertion of COL in colli-
`sion test mode
`
`Subclause
`
`22.2.4.l.9
`
`Reserved bits written as zero
`
`22.2.4.l.l0
`
`Reserved bits ignored when
`read
`
`22.2.4.1.10
`
`PHY returns 0 in reserved bits
`
`22.2.4.l.l0
`
`Effect of write on status register
`
`Reserved bits ignored when
`read
`
`22.2.4.2
`
`22.2.4.2.6
`
`PHY returns 0 in reserved bits
`
`22.2.4.2.6
`
`PHY returns 0 ifAuto-Negotia-
`tion disabled
`
`PHY returns 0 if it lacks ability
`to perform Auto-Negotiation
`
`Remote fault has latching
`function
`
`22.2.4.2.8
`
`22.2.4.2.8
`
`22.2.4.2.9
`
`IEEE
`Std 802.3, 1998 Edition
`
`Value/Comment
`
`Within 4 BT after TX_EN is
`de-asserted
`
`Yes (1.5 = 0 when 0.12 = 0)
`
`Yes (1.5 = 0 when 1.3 = 0)
`
`Yes (once set will remain set
`until cleared)
`
`Remote fault cleared on read
`
`22.2.4.2.9
`
`Yes
`
`Remote fault cleared on reset
`
`22.2.4.2.9
`
`PHY without remote fault re-
`turns value of zero
`
`Link status has latching
`fimction
`
`22.2.4.2.9
`
`22.2.4.2.1l
`
`Jabber detect has latching func-
`tion
`
`22.2.4.2.l2
`
`Jabber detect cleared on read
`
`22.2.4.2.l2
`
`Jabber detect cleared on reset
`
`22.2.4.2.l2
`
`l00BASE-T4 and l00BASE-X
`PHYs return 0 for jabber detect
`
`22.2.4.2.l2
`
`MDIO not driven if register
`read is unimplemented
`
`Write has no efiect if register
`written is unimplemented
`
`Registers 2 and 3 constitute
`unique identifier for PHY type
`
`22.2.4.3
`
`22.2.4.3
`
`22.2.4.3.l
`
`MSB of PHY identifier is 2.15
`
`22.2.4.3.l
`
`LSB of PHY identifier is 3.0
`
`22.2.4.3.l
`
`Composition of PHY identifier
`
`Format of management frames
`
`22.2.4.3.l
`
`22.2.4.4
`
`Yes (when 0.15 = 1)
`
`Yes (1.4 always 0)
`
`Yes (once cleared by link fail-
`ure will remain cleared until
`read by MII)
`
`Yes (once set will remain set
`until cleared)
`
`Yes (1.1 always = 0 for
`l00BASE-T4 and l00BASE-
`TX)
`
`Yes (MDIO remain high im-
`pedance)
`
`22-bit OUI, 6-bit model, 4-bit
`version per figure 22-12
`
`Per table 22-9
`
`This is arbelgfigig/@1EfiEE§tanggrg,e,ltflhas been superseded by a later version of this standard.
`
`Aerohive - Exhibit 1025
`
`0093
`
`Aerohive - Exhibit 1025
`0093
`
`
`
`IEEE
`Std 802.3, 1998 Edition
`
`LOCAL AND METROPOLITAN AREA NETWORKS:
`
`Subclause
`
`Value/Comment
`
`Idle condition on MDIO
`
`22.2.4.4.1
`
`High impedance state
`
`MDIO preamble sent by STA
`
`22.2.4.4.2
`
`MDIO preamble observed by
`PHY
`
`22.2.4.4.2
`
`Assignment of PHYAD 0
`
`22.2.4.4.5
`
`Assignment of REGAD 0
`
`22.2.4.4.6
`
`Assignment of REGAD 1
`
`High impedance during first bit
`time of turnaround in read
`transaction
`
`22.2.4.4.6
`
`22.2.4.4.7
`
`PHY drives zero during second
`bit time of turnaround in read
`transaction
`
`22.2.4.4.7
`
`STA drives MDIO during turn-
`around in write transaction
`
`22.2.4.4.7
`
`First data bit transmitted
`
`22.2.4.4.8
`
`32 contiguous logic one bits
`
`32 contiguous logic one bits
`
`Address of PHY attached via
`Mechanical Interface
`
`MII control register address
`
`MII status register address
`
`Bit 15 of the register being ad-
`dressed
`
`This is anygrchive IEEE Standard.
`
`It has been superseded byogplgggrg/g§§iggEg(..tI{gsss;agag@rd.
`
`Aerohive - Exhibit 1025
`
`0094
`
`Aerohive - Exhibit 1025
`0094
`
`
`
`CSMA/CD
`
`22.7.3.5 Signal timing characteristics
`
`IEEE
`Std 802.3, 1998 Edition
`
`Subclause
`
`Value/Comment
`
`Timing characteristics mea-
`sured in accordance with
`annex 22C
`
`Transmit signal clock to output
`delay
`
`Receive signal setup time
`
`Receive signal hold time
`
`MDIO setup and hold time
`
`per figure 22-17
`
`Min = 0 ns; Max = 25 ns
`per figure 22-14
`
`Min = 10 ns per figure 22-15
`
`Min = 10 ns per figure 22-15
`
`Setup min = 10 ns; Hold min =
`10 ns per figure 22-l6
`
`Min = 0 ns; Max = 300 ns
`
`MDIO clock to output delay
`
`22.7.3.6 Electrical characteristics
`
`Feature
`
`Subclause
`
`Value/Comment
`
`Signal paths are either point to
`point, or a sequence of point-
`to-point transmission paths
`
`MII uses unbalanced signal
`transmission paths
`
`Characteristic impedance of
`electrically long paths
`
`Output impedance of driver
`used to control reflections
`
`Voh
`
`V01
`
`Performance requirements to
`be guaranteed by ac specifica-
`tions
`
`Vih(min)
`
`Vil(max)
`
`Input current measurement
`point
`
`Input current reference poten-
`tials
`
`Input current reference poten-
`tial range
`
`Input current limits
`
`68 Q :: 15%
`
`On all electrically long point to
`point signal paths
`
`2 2.4 v (10,, = 4 mA)
`
`s o.4v(101= 4 mA)
`
`Min switching potential change
`(including its reflection) 2 1.8 V
`
`2V
`
`0.8V
`
`At MII connector
`
`Reference to MII connector
`+5 V and COMMON pins
`
`0Vto 5.25V
`
`Per table 22-10
`
`This is arbei£fiE|iy@1Efi&§Ifin§igr,d,e,lLj]aS been superseded by a later version of this standard.
`
`Aerohive - Exhibit 1025
`
`0095
`
`Aerohive - Exhibit 1025
`0095
`
`
`
`IEEE
`Std 802.3, 1998 Edition
`
`LOCAL AND METROPOLITAN AREA NETWORKS:
`
`Subclause
`
`Value/Comment
`
`Input capacitance for signals
`other than MDIO
`
`Input capacitance for MDIO
`
`Twisted-pair composition
`
`Single-ended characteristic im-
`pedance
`
`Characteristic impedance mea-
`surement method
`
`Twisted-pair propagation delay
`
`Twisted-pair propagation delay
`measurement method
`
`Twisted-pair propagation delay
`measurement frequency
`
`Twisted-pair propagation delay
`variation
`
`Twisted-pair propagation delay
`variation measurement method
`
`Cable shield termination
`
`Cable conductor DC resistance
`
`Effect of hot insertion/removal
`
`State of PHY output buffers
`during hot insertion
`
`State of PHY output buffers af-
`ter hot insertion
`
`S8pF
`
`Sl0pF
`
`Conductor for each signal with
`dedicated return path
`
`68 Q :: 10%
`
`With return conductor connect-
`ed to cable shield
`
`S 2.5 ns
`
`With return conductor connect-
`ed to cable shield
`
`25 MHz
`
`$0.1 ns
`
`With return conductor connect-
`ed to cable shield
`
`To the connector shell
`
`S 150 m9
`
`Causes no damage
`
`High impedance
`
`High impedance until enabled
`via Isolate bit
`
`This is angArchive IEEE Standard.
`
`It has been superseded byogplgggrg/g§§iggEg(..tI{g§ss;agag@rd.
`
`Aerohive - Exhibit 1025
`
`0096
`
`Aerohive - Exhibit 1025
`0096
`
`
`
`CSMA/CD
`
`22.7.3.7 Power supply
`
`IEEE
`Std 802.3, 1998 Edition
`
`Subclause
`
`Value/Comment
`
`Regulated power supply
`provided
`
`Power supply lines
`
`Regulated supply voltage limits
`
`Over/under voltage limits
`
`Load current limit
`
`Surge current limit
`
`PHY can power up from cur-
`rent limited source
`
`Short-circuit protection
`
`To PHY by Reconciliation
`sublayer
`
`-5 V and COMMON (return of
`——5 v)
`
`5 Vdc :: 5%
`
`Over limit = 5.25 Vdc
`Under limit = 0 V
`
`750 mA
`
`S 5 A peak for 10 ms
`
`From 750 mA current limited
`source
`
`When +5 V and COMMON are
`
`shorted
`figure 22-19
`
`22.7.3.8 Mechanical characteristics
`
`Feature
`
`Subclause
`
`Value/Comment
`
`Use of Mechanical Interface
`
`Connector reference standard
`
`Use of female connector
`
`Use of male connector
`
`Connector shell plating
`
`Shield transfer impedance
`
`Additions to provide for female
`shell to male shell conductivity
`
`Clearance dimensions
`
`Optional
`IEC 1076-3-101: 1995
`
`At MAC/RS side
`
`At PHY mating cable side
`
`Use conductive material
`
`After 500 cycles of mating/
`unmating, per table 22-ll
`
`On shell of conductor with
`male contacts
`
`15 mm X 50 mm, per
`
`This is arbeigfigig/@1EfiEE§tanggrg,e,lL@as been superseded by a later version of this standard.
`
`Aerohive - Exhibit 1025
`
`0097
`
`Aerohive - Exhibit 1025
`0097
`
`
`
`CSMNCD
`
`IEEE
`Std 802.3u-1995
`
`23. Physical Coding Sublayer (PCS), Physical Medium Attachment (PMA)
`sublayer and baseband medium, type 100BASE-T4
`
`23.1 Overview
`
`The 100BASE-T4 PCS, PMA, and baseband medium specifications are aimed at users who want 100 Mb/s
`performance, but would like to retain the benefits of using voice-grade twisted-pair cable. 100BASE-T4 sig-
`naling requires four pairs of Category 3 or better cable, installed according to ISO/IEC 11801: 1995, as
`specified in 23.6. This type of cable, and the connectors used with it, are simple to install and reconfigure.
`100BASE-T4 does not transmit a continuous signal between packets, which makes it 11S6fl1l in battery pow-
`ered applications. The 100BASE-T4 PHY is one of the 100BASE-T family of high-speed CSMA/CD net-
`work specifications.
`
`23.1.1 Scope
`
`This clause defines the type 100BASE-T4 Physical Coding Sublayer (PCS), type 100BASE-T4 Physical
`Medium Attachment (PMA) sublayer, and type 100BASE-T4 Medium Dependent Interface (MDI).
`Together, the PCS and PMA layers comprise a 100BASE-T4 Physical Layer (PHY). Provided in this docu-
`ment are full fimctional, electrical, and mechanical specifications for the type 100BASE-T4 PCS, PMA, and
`MDI. This clause also specifies the baseband medium used with 100BASE-T4.
`
`23.1.2 Objectives
`
`The following are the objectives of 100BASE-T4:
`
`a)
`b)
`c)
`d)
`
`e)
`
`f)
`
`To support the CSMA/CD MAC.
`To support the 100BASE-T M11, Repeater, and optional Auto—Negotiation.
`To provide 100 Mb/s data rate at the M11.
`To provide for operating over unshielded twisted pairs of Category 3, 4, or 5 cable, installed as hori-
`zontal runs in accordance with ISO/IEC 11801: 1995, as specified in 23.6, at distances up to 100 m
`(328 ft).
`To allow for a nominal network extent of 200 in, including:
`1) Unshielded twisted-pair links of 100 m.
`2)
`Two-repeater networks of approximately a 200 m span.
`To provide a communication channel with a mean ternary symbol error rate, at the PMA service
`interface, of less than one part in 108.
`
`23.1.3 Relation of 100BASE-T4 to other standards
`
`Relations between the 100BASE-T4 PHY and the ISO Open Systems Interconnection (OSI) reference
`model and the IEEE 802.3 CSMA/CD LAN model are shown in figure 23-1. The PHY Layers shown in fig-
`ure 23-1 connect one clause 4 Media Access Control GVIAC) layer to a clause 27 repeater. This clause also
`discusses other variations of the basic configuration shown in figure 23-1. This whole clause builds on
`clauses 1 through 4 of this standard.
`
`23.1.4 Summary
`
`The following paragraphs summarize the PCS and PMA clauses of this document.
`
`23.1.4.1 Summary of Physical Coding Sublayer (PCS) specification
`
`The 100BASE-T4 PCS couples a Media Independent Interface (M11), as described in clause 22, to a Physical
`Medium Attachment sublayer (PMA).
`
`This is an Archive IEEE Standard.
`
`It has been superseded by a later version of this standard.
`
`it 1025
`
`0098
`
`
`
`Aerohive - Exhibit 1025
`0098
`
`
`
`IEEE
`Std 8D2_3u—1995
`
`SUPPLEMENT TO 802.3:
`
`OSI
`REFERENCE
`MOD EL
`LAYERS
`
`LAN
`CSMNCD
`LAYERS
`
`APPLICATION
`
`HIGHER LAYERS
`
`PRESENTATION
`
`LLC—LOG|CAL LINK CONTROL
`
`MAC—MEDlA ACCESS CONTROL
`
`RECONCILIATION
`
`SESSION
`
`TRANSPORT
`NETWORK
`
`DATA LINK
`
`PHYSICAL
`
`-ED'UM To 100 Mbls Baseband Repeater Set
`or to 1tJDBASE—T4 PHY (point—to—point link)
`
`MDI = MEDIUM DEPENDENT INTERFACE
`MII = MEDIA INDEPENDENT INTERFACE
`
`PCS = PHYSICAL CODING SUBLAYER
`PMA = PHYSICAL MEDIUM ATTACHMENT
`PHY = PHYSICAL LAYER DEVICE
`
`‘ MII is optional.
`“' AUTONEG communicates with the PMA suhlayer through the PMA service interface messages
`PMA_L|NK_request and PMA_L|NK_indicate_
`"“" AUTONEG is optional.
`
`Figure 23-1—Type 10llBASE-T4 PHY relationship to the ISO Open Systems
`Interconnection {OSI) reference model and the IEEE 802.3 CSMAICD LAN model
`
`The PCS Transmit function accepts data nibbles fiom the M11. The PCS Transmit function encodes these
`nibbles using an 8B6T coding scheme (to be described} and passes the resulting ternary symbols to the
`PMA. In the reverse direction, the PMA conveys received ternary symbols to the PCS Receive function. The
`PCS Receive function decodes them into octets, and then passes the octets one nibble at a time up to the MII.
`The PCS also contains a PCS Carrier Sense function. a PCS Error Sense function, a PCS Collision Presence
`function, and a management interface.
`
`Figure 23-2 shows the division of responsibilities between the PCS, PMA, and MDI layers.
`
`Physical level communication between PHY entities takes place over four twisted pairs. This specification
`permits the use of Category 3. 4, or 5 unshielded twisted pairs, installed according to ISOKIEC 11801: 1995,
`as specified m 23.6. Figure 23-3 shows how the PHY manages the four twisted pairs at its disposal.
`
`The IOOBASE-T4 transmission algorithm always leaves one pair open for detecting ca.rrier from the far end
`(see figure 23-3). Leaving one pair open for carrier detection in each direction greatly simplifies media access
`control. All collision detection functions a1'e accomplished using only the unidirectional pairs TX_DI and
`R.X_D2, in a manner
`to l0BASE—T. This collision detection strategy leaves three pairs in each direction
`free for data transmission, which uses an SB6T block code, schematically represented in figure 23-4.
`
`8B6T coding, as used with IOOBASE-T4 signaling, maps data octets into ternary symbols. Each octet is
`mapped to a pattern of 6 ternary symbols, called at 6T code group. The 6T code groups are fanned out to
`three independent serial channels. The efiective data rate carried on each pair is one third of 100 II/Ib/s,
`
`This is angfilrchive IEEE Standard.
`
`It has been superseded by a later version of this standard.
`
`Aerohive - Exhibit 1025
`0099
`
`
`
`CSMNCD
`
`IEEE
`Std BIE|2_3u—1995
`
`Opijanai ciause 28: link_c0ntrol
`
`q—p Management interface has
`pervasive connecijnns to all blocks
`link_slalus
`
`|_|NK
`INTEGRITY
`
`TX_CLK 4}
`TXD‘330>?F
`
`PCS
`
`“-5”
`
`TX_ER RF TRANSIVIIT
`
`COL 4
`
`CR3 4-‘
`
`PCS CARRIER
`SENSE
`
`Rx_cLK-1:
`RxD<3;u>«-1:
`RX W4?
`
`PCS
`RECEIVE
`
`dc_halanI:e_ermr
`eop_ern)r
`
`co-dewDrd_errDr L
`
`1:: code eiement
`
`i _ l _
`
`PCS
`COLLISION
`PRESENCE
`
`D
`
`TRANSMIT
`
`PMA
`
`TCfim'ef_SI3I1l-I5
`
`PMA CARRIER
`
`SENSE
`
`Rx_ER.._ PCS ERROR
`SENSE E
`l
`
`MEDIA
`INTERFACE
`(Mil)
`4
`
`4
`
`F 4
`
`PHY
`(INCLUDES PCS AND PMA)
`
`PMA
`RECEIVE
`
`i
`CLOCK
`
`MEDIUM
`
`W9‘)
`
`F
`
`p
`
`Figure 23-2—Division of responsibilities between 100BASE-T4 PCS and PMA
`
`TX_ D1
`
`RX_ D2
`
`BI D3
`
`DQIIECI
`collisions
`on RX_D2
`
`Repeater with internai crossover
`(crossover is cipti0na|—see 23.7.2)
`
`Figure 23-3—Use of wire pairs
`
`This is an Archive IEEE Standard.
`
`It has been superseded by a later version of this standgd.
`
`Aerohive - Exhib
`
`Aerohive - Exhibit 1025
`0100
`
`
`
`IEEE
`Std 8D2.3u—1995
`
`SUPPLEMENT TO 802.3:
`
`input data stream
`I
`I
`I
`I
`
`6T code group formed from one octet
`2
`3
`4
`6
`
`1
`
`l
`
`Each ternary
`* symbol 2 40 ns
`
`Figure 23-4—8B6T coding
`
`which is 33.3.33... Mbls. The ternary symbol transmission rate on each pair is 6/8 times 33.33 Mb/s, or pre-
`cisely 25.000 MHZ.
`
`Refer to annex 23A for a complete listing of 8B6T code words.
`
`The PCS functions and state diagrams are specified in 23.2. The PCS electrical interface to the MII conforms
`to the ir1terface requirements of clause 21. The PCS interface to the PMA is an abstract message-passing
`interface specified ir1 23.3.
`
`23.1.4.2 Summary of physical medium attachment {PMA} specification
`
`The PMA couples messages from the PMA service interface onto the twisted-pair physical medium. The
`PMA provides communications. at 100 Mb./s, over fou1' pairs of twisted-pair wiring up to 100 m in length.
`
`The PMA T1'ansrnit function, shown ir1 figure 23-2, comprises three independent ternary data transmitters.
`Upon receipt of a PlVIA_UNITDATA request message, the PMA synthesizes one ternary symbol o11 each of
`the three output channels (IX_D1, BI_D3. and BI_D4). Each output driver has a temaijv output. meaning
`that the output waveform can assume any of three values, corresponding to the transmission of ternary sym-
`bols CS0, CS1 or CS-1 (see 23.4.3.1) on each of the twisted pairs.
`
`The PMA Receive function comprises three independent ternary data receivers. The receivers are responsi-
`ble for acquiring clock, decoding the Start of Stream Delirniter (SSD) on each channel, and providing data to
`the PCS in the synchronous fashion defined by the PMA_UNTTDATA.indicate message. The PMA also con-
`tains functions for PMA Carrier Sense and Link Integrity.
`
`PMA functions and state diagrams appear in 23.4. PMA electrical specifications appear in 23.5.
`
`23.1.5 Application of100BASE-T4
`
`23.1.5.1 Compatibility considerations
`
`All implementations of the twisted-pair link shall be compatible at the MDI. The PCS. PMA, and the
`medium are defined to provide compatibility among devices designed by different manufacturers. Designers
`are fi'ee to implement circuitry within the PCS and PMA (m an application-dependent manner) provided the
`MDI (and M1], when implemented) specifications are met.
`
`23.1.5.2 Incorporating the 100BASE-T4 PHY into a DTE
`
`The PCS is required when used with a DTE. The PCS provides functions necessary to the overall system
`operation {such as SB6T coding) and cannot be omitted. Refer to figure 23-].
`
`This is angarchive IEEE Standard.
`
`It has been superseded by a later version of this standard.
`
`Aerohive - Exhibi
`
`Aerohive - Exhibit 1025
`0101
`
`
`
`CSMA/CD
`
`IEEE
`Std 8D2.3u-1995
`
`When the PHY is incorporated within the physical bounds of a DTE, conformance to the MII interface is
`optional, provided that the observable behavior of the resulting system is identical to a system with a full
`MII implementation. For example, an integrated PHY may incorporate an interface between PCS and MAC
`that is logically equivalent to the M11, but does not have the full output current drive capability called for in
`the MII specification.
`
`23.1.5.3 Use of 100BASE-T4 PHY for point-to-point communication
`
`The 100BASE-T4 PHY, in conjunction with the MAC specified in clauses l-4 (including parameterized val-
`ues in 4.4.2.3 to support 100 Mb/s operation), may be used at both ends of a link for point-to-point applica-
`tions between two DTEs. Such a configuration does not require a repeater. In this case each PHY may
`connect through an MII to its respective DTE. Optionally, either PHY (or both PHYs) may be incorporated
`into the DTEs without an exposed lVlII.
`
`23.1 .5.4 Support for Auto-Negotiation
`
`The PMA service interface contains primitives used by the Auto-Negotiation algorithm (clause 28) to auto-
`matically select operating modes when connected to a like device.
`
`23.2 PCS functional specifications
`
`The 100BASE-T4 PCS couples a Media Independent Interface (M11), as described in clause 22, to a
`100BASE-T4 Physical Medium Attachment sublayer (PMA).
`
`At its interface with the MII, the PCS communicates via the electrical signals defined in clause 22.
`
`The interface between PCS and the next lower level (PMA) is an abstract message-passing interface
`described in 23.3. The physical realization of this interface is left to the implernentor, provided the require-
`ments of this standard, where applicable, are met.
`
`23.2.1 PCS functions
`
`The PCS comprises one PCS Reset function and five simultaneous and asynchronous operating functions.
`The PCS operating fimctions are PCS Transmit, PCS Receive, PCS Error Sense, PCS Carrier Sense, and
`PCS Collision Presence. A11 operating functions start immediately after the successful completion of the
`PCS Reset function.
`
`The PCS reference diagram, figure 23-5, shows how the five operating fimctions relate to the messages of
`the PCS-PMA interface. Connections fi'om the management interface (signals MDC and MDIO) to other
`layers are pervasive, and are not shown in figure 23-5. The management functions are specified in clause 30.
`See also figure 23-6, which defines the structure of fi'ames passed from PCS to PMA. See also figure 23-7,
`which presents a reference model helpful for understanding the definitions of PCS Transmit fimction state
`variables ohrl-4 and tsr.
`
`23.2.1.1 PCS Reset function
`
`The PCS Reset function shall be executed any time either of two conditions occur. These two conditions are
`“power on” and the receipt of a reset request from the management entity. The PCS Reset function initializes
`all PCS functions. The PCS Reset fimction sets pcs_reset S ON for the duration of its reset fimction. All state
`diagrams take the open-ended pcs_reset branch upon execution of the PCS Reset fimction. The reference
`diagrams do not explicitly show the PCS Reset function.
`
`This is an Archive IEEE Standard.
`
`It has been superseded by a later version of this standgd.
`
`102
`
`1025
`
`Aerohive - Exhibit 1025
`0102
`
`
`
`IEEE
`Std 8D2_3u—1995
`
`SUPPLEMENT TO 802.3:
`
`_
`
`P05
`
`tx_code_e|ement
`
`|ink_status
`
`Tx_EN —r>
`
`TX_ER :3. TRANSMIT
`
`COL 4
`
`PCS CARRIER
`CR5 4_ SENSE
`
`l
`
`L
`
`5
`
`PCS
`COLLISION
`
`PRESENCE
`
`PCS
`RECEIVE
`
`RX_CLK -1:
`RXD-<3:D> 4:
`RX_DV <—
`oodeword_error
`dc_ba|ance_error
`eop_error
`
`4-
`
`carrier_status
`
`rx_code_vectoI
`
`R)(_ER 4? PCS ERROR
`SENSE
`
`Stat
`rxerror_
`
`US
`
`MEDIA
`INDEPENDENT
`|NTER FACE
`(Mil)
`
`PMA SERVICE
`INTERFACE
`
`Figure 23-5—PCS reference diagram
`
`23.2.1.2 PCS Transmit function
`
`The PCS Transmit fimction shall conform to the PCS Transmit state diagram in figure 23-8.
`
`The PCS Transmit function receives nibbles from the TXD signals of the ME, assembles pairs of nibbles to
`form octets, converts the octets into 6T code groups according to the 8B6T code table, and passes the result-
`ir1g ternary data to the PMA using the PMA_UNITDATA request message. The state diagram of figure 23-8
`depicts the PCS Transmit function operation. Definitions of state Variables tsr, ohr, sosa, sosb, eopl-5, and
`tx_extend used in that diagram. as well as in the following text, appear in 23.2.4.1. The physical structure
`represented in figure 23-7 is not required; it merely serves to explain the meaning of the state diagram vari-
`ables ohr and tsr in figure 23-8. Implementors a1'e free to construct any logical devices having functionality
`identical to that described by this functional description and the PCS Transmit state diagram, figure 23-S.
`
`PCS Transmit makes use of the tsr and ohr shift registers to manage nibble assembly and ternary symbol
`transmission. Nibbles from the M11 go into tsr, which PCS Transmit reads as octets. PCS Transmit then
`encodes those octets and writes 6T code groups to the ohr registers. The PMA_UN'ITDATA.request message
`passes ternary symbols from the ohr registers to the PMA. In each state diagram block, the ohr loading oper-
`ations are conducted first, then tX_code_vector is loaded and the state diagram waits 40 ns.
`
`The first 5 octets assembled by the PCS Transmit function are encoded into the sosa code word and the next
`3 octets assembled a1'e encoded into the sosb code word. This guarantees that every packet begins with a
`valid preamble pattern. This is accomplished by the definition of tsr. In addition, the PCS Transmit state dia-
`gram also specifies that at the start of a packet all three output holding registers ohrl, ohr3 and ohr4 will be
`loaded with the same value (sosa). This produces the ternary symbols labeled P3 and P4 in figure 23-6.
`
`This is angeirchive IEEE Standard.
`
`It has been superseded by a later version of this standard.
`
`Aerohive - Exhibi
`
`Aerohive - Exhibit 1025
`0103
`
`
`
`CSMA/CD
`
`IEEE
`Std 802.3u-1995
`
`At the conclusion of the MAC frame, the PCS Transmit function appends eopl—5. This is accomplished by
`defining a variable tx_extend to stretch the TX_EN signal, and defining tsr during this time to be a sequence
`of constants that decodes to the proper eop code groups.
`
`The encoding operation shall use the 8B6T code table listed in annex 23A, and the dc balance encoding rules
`listed below. Encoding is performed separately for each transmit pair.
`
`23.2.1.2.1 DC balance encoding rules
`
`The encoding operation maintains dc balance on each transmit pair by keeping track of the cumulative
`weight of all 6T code groups (see weight of 6T code gmup, annex 21A) transmitted on that pair. For each
`pair, it initiates the cumulative weight to 0 when the PCS Transmit fimction is in the AWAITING DATA TO
`TRANSIVHT state. All 6T code groups in the code table have weight 0 or 1. The dc balance algorithm condi-
`tionally negates transmitted 6T code groups, so that the code weights transmitted on the line include 0, +1,
`and -1. This dc balance algorithm ensures that the cumulative weight on each pair at the conclusion of each
`6T code group is always either 0 or 1, so only one bit per pair is needed to store the cumulative weight. As
`used below, the phrase “invert the cumulative weight bit” means “if the cumulative weight bit is zero then set
`it to one, otherwise set it to zero.”
`
`Afier encoding any octet, except the constants sosa, sosb, eopl-5 or bad_code, update the cumulative weight
`bit for the affected pair according to rules a) through c):
`
`a)
`b)
`c)
`
`If the 6T code group weight is 0, do not change the cumulative weight.
`Ifthe 6T code group weight is 1, and the cumulative weight bit is 0, set the cumulative weight bit to l.
`If the 6T code group weight is l, and the cumulative weight bit is also 1, set the cumulative weight
`bit to 0, and then algebraically negate all the ternary symbol values in the 6T code group.
`
`Afier encoding any of the constants sosa, sosb, or bad_code, update the cumulative weight bit for the
`alfected pair according to rule d):
`
`d) Do not change the cumulative weight. Never negate sosa, sosb or bad_code,
`
`Afier encoding any of the constants eopl-5, update the cumulative weight bit for the affected pair according
`to rules e) and f):
`
`e)
`
`f)
`
`If the cumulative weight is 0, do not change the cumulative weight; algebraically negate all the ter-
`nary symbol values in eopl-5.
`If the cumulative weight is 1, do not change the cumulative weight.
`
`NOTE—The inversion rules for eopl-5 are opposite rule b). That makes eopl -5 look very unlike normal data, increasing
`the number of errors required to synthesize a false end-of-packet marker.
`
`23.2.1.3 PCS Receive function
`
`The PCS Receive function shall conform to the PCS Receive state diagram in figure 23-9.
`
`communicated via the
`from the PMA,
`ternary symbols
`function accepts
`The PCS Receive
`PMA_UNITDATA.indicate message, converts them using 8B6T coding into a nibble-wide format and
`passes them up to the M11. This fimction also generates RX_DV. The state diagram of figure 23-9 depicts the
`PCS Receive function. Definitions of state variables ih2, ih3, and ih4 used in that diagram, as well as in the
`following text, appear in 23.2.4.1.
`
`The last 6 values of the rx_code_vector are available to the decoder. PCS Receive makes use of these stored
`rx_code_vector values as well as the ih2—4 registers to manage the assembly of ternary symbols into 6T code
`
`This is an Archive IEEE Standard.
`
`It has been superseded by a later version of this standard.
`
`0104
`
`it 1025
`
`Aerohive - Exhibit 1025
`0104
`
`
`
`IEEE
`Std 802.3u-1995
`
`SUPPLEMENT TO 802.3:
`
`groups, and the conversion of decoded data octets into nibbles. The last 6 ternary symbols for pair BI_D3 (as
`extracted from the last 6 values of rx_code_vector) are referred to in the state diagram as BI_D3[0:5]. Other
`pairs are referenced accordingly.
`
`The PCS Receive state diagram starts the first time the PCS receives a PMA_UNITDATA.indicate message
`with rx_code_vector=DATA (as opposed to IDLE or PREAMBLE). The contents of this
`first
`PMA_UNITDATA.indicate (DATA) message are specified in 23.4.1.6.
`
`there is
`Afier the sixth PMA_UNITDATA.indicate (DATA) message (state DECODE CHANNEL 3),
`enough information to decode the first data octet. The decoded data is transmitted across the MII in two
`parts, a least significant nibble followed by a most significant nibble (see clause 22).
`
`During state COLLECT 4TH TERNARY SYMBOL the PCS Receive function raises RX_DV and begins
`shifting out the nibbles of the 802.3 MAC SFD, least significant nibble first (SFD:LO). The most significant
`nibble of the 802.3 MAC SFD, called SFD:HI, is sent across the M11 during the next state, COLLECT 5TH
`TERNARY SYMBOL.
`
`Once eop is signaled by the decode operation, the state diagram de-asserts RX_DV, preventing the end-of-
`packet bits from reaching the MH. At any time that RX_DV is de-asserted, RXD<3:0> shall be all zeroes.
`
`The decode operation shall use the 8B6T code table listed in annex 23A, and the error-detecting rules listed
`in 23.2.1.3.1. Decoding and maintenance of the cumulative weight bit is performed separately for each
`receive pair.
`
`23.2.1.3.1 Error-detecting rules
`
`The decoding operation checks the dc balance on each receive pair by keeping track of the cumulative
`weight of all 6T code group received on that pair. For each pair, initialize the cumulative weight to 0 when
`the PCS Receive function is in the AWAITING INPUT state. As in the encoding operation, only one bit per
`pair is needed to store the cumulative weight.
`
`Before decoding each octet, check the weight of the incoming code group and then apply rules a) through h)
`in sequence:
`
`a)
`
`b)
`
`c)
`
`d)
`
`e)
`
`f)
`
`g)
`
`h)
`
`If the received code group is eopl (or its negation), set eop=ON. Then check the other pairs for con-
`formance to the end—of—packet rules as follows: Check the last four ternary symbols of the next pair,
`and the last two ternary symbols from the third pair for exact conformance with the end-of-packet
`pattern specified by PCS Transmit, including the cumulative weight negation rules. If the received
`data does not conform, set the internal variable eop_error=ON. Skip the other rules.
`If the received code group weight is greater than 1 or less than -1, set the internal variable
`dc_balance_error=ON. Decode to all zeros. Do not change the cumulative weight.
`If the received code group weight is zero, use the code table to decode. Do not change the cumula-
`tive weight.
`If the received code group weight is +1, and the cumulative weight bit is 0, use the code table to
`decode. Invert the cumulative weight bit.
`If the received code group weight is -1, and the cumulative weight bit is 1, algebraically negate each
`ternary symbol in the code group and then use the code table to decode. Invert the cumulative weight
`bit.
`
`If the received code group weight is +1 and the cumulative weight bit is 1, set the internal variable
`dc_balance_error=ON. Decode to all zeros. Do not change the cumulative weight.
`If the received code group weight is -1 and the cumulative weight bit is 0, set the internal variable
`dc_balance_error=ON. Decode to all zeros. Do not change the cumulative weight.
`If the (possibly negated) code group is not found in the code table, set codeword_error =ON. Decode
`to all zeros. Do not change the cumulative weight.
`
`This is anggtrchive IEEE Standard.
`
`It has been superseded by a later version of this standard.
`
`0105
`
`1025
`
`Aerohive - Exhibit 1025
`0105
`
`
`
`CSMA/CD
`
`IEEE
`Std 8D2.3u-1995
`
`The variables dc_balance_error, eop_error and codeword_error shall remain OFF at all times other than
`those specified in the above error-detecting rules.
`
`The codeword_error=ON indication for a (possibly negated) code group not found in the code table shall set
`RX_ER during the transfer of both affected data nibbles across the MD.
`
`The dc_balance_error=ON indication for a code group shall set RX_ER during the transfer of both aifected
`data nibbles across the NHL
`
`The eop_error=ON indication shall set RX_ER during the transfer of the last decoded data nibble of the pre-
`vious octet across the MII. That
`is at
`least one RX_CLK perio