Receive Frame Status Word | SMC Networks SMC91C95 instruction

RECEIVE FRAME STATUS WORD

This word is written at the beginning of each receive frame in memory. It is not available as a register.

HIGH	ALGN	BROD	BAD	ODD	TOOLN	TOO
BYTE	ERR	CAST	CRC	FRM	TOOLN	SHORT
BYTE	ERR	CAST	CRC	FRM	G	SHORT
					G
LOW
LOW				HASH VALUE				MULT
BYTE								CAST
		5	4	3	2	1	0

ALGNERR - Frame had alignment error.

BRODCAST - Receive frame was broadcast.

BADCRC - Frame had CRC error.

ODDFRM - This bit when set indicates that the received frame had an odd number of bytes.

TOOLNG - The received frame is longer than 802.3 maximum size (1518 bytes on the cable).

TOOSHORT - The received frame is shorter than 802.3 minimum size (64 bytes on the cable).

HASH VALUE - Provides the hash value used to index the Multicast Registers. Can be used by receive routines to speed up the group address search. The hash value consists of the six most significant bits of the CRC calculated on the Destination Address, and maps into the 64 bit multicast table. Bits 5,4,3 of the hash value select a byte of the multicast table, while bits 2,1,0 determine the bit within the byte selected.

Examples of the address mapping:

ADDRESS	HASH VALUE 5-0	MULTICAST TABLE BIT
ED 00 00 00 00 00	000 000	MT-0 bit 0
0D 00 00 00 00 00	010 000	MT-2 bit 0
01 00 00 00 00 00	100 111	MT-4 bit 7
2F 00 00 00 00 00	111 111	MT-7 bit 7

MULTCAST - Receive frame was multicast. If hash value corresponds to a multicast table bit that is set, and the address was a multicast, the

packet will pass address filtering regardless of other filtering criteria.

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SMC Networks SMC91C95 manual Receive Frame Status Word, Address Hash Value Multicast Table BIT

Contents

Bus Interface Features Table of Contents Network Interface PIN ConfigurationSoftware Drivers Overview General DescriptionPage ISA Uses non-volatile jumperless setup via serial EepromPcmcia PIN Requirements Function ISA Pcmcia Number Pins Coln Crystal OSC XTAL1 XTAL2 Power VDD Avdd Ground GNDTotal Pins Recp Description of PIN Functions PIN no Name Symbol Type Description Reset ISA Byte High Enable input. Asserted lowPcmcia Card Enable 2 input. Used to Enable Select card on odd byte accesses Ready Register. This interrupt is tri-stated when not Application of the VCC or Reset which everISA Output. Active high interrupt signal. Value of INT SEL1-0 bits in the Configuration Interrupt pin if enabled Whenever the SMC91C95 is in 16 bit modeEnable Function bit in the Ecor Is with Input. Active low read strobe used to access Pin when enabled by the Audio bit Modem Pin is active high when either the PwrdwnOutput B Powerdown mode Pwrdwn bit is zero Value of the Mringin input. When entering Sdout Eeprom Eeprom EeskEeprom Eecs Eeprom Eedo AUI RxclkTXD Register TPE Tpetxdp Tperxn TPE TpetxpTxclk Buffer Types EndecVSS Avss SMC91C95 SMC91C95 SMC91C95 Internal Block Diagram BIT Mode Bus Transactions in ISA Mode NSBHE D0-D7 D8-D15Functional Description Even byte Bus Transactions in Pcmcia Mode NCE1 NCE2 D0-D7 D8-D15Even byte IOis8=1 + nEN16=1.16BIT=0 No Cycle SMC91C95 Address Spaces Signals ISA Pcmci ON-CHIP Depth Width UsedROM Buffer Memory Mapping and Paging VS. Receive and TX Area TX Completion CPU Side TX FifoFifo Receive Queue and Mapping With Block DiagramSMC91C95 Internal Transmit Packet Receive Packet Packet Format in Buffer Memory ODD ODD CRCByte before the Control Byte should be ignored Address Hash Value Multicast Table BIT Receive Frame Status Word SMC91C95 Interrupt Merging Function Pcmcia Mode ISA ModeInterrupt Output NIREQ when either function is Interrupt Structure Mcor Reset LogicReset Functions Ecor Pwrdwn Powerdown LogicPowerdown Functions Powerdown Powers Does not Entered Exited Power Down Pcmcia Attribute Memory Address 0- 7FFEh Pcmcia Configuration Registers Address 8000-803Eh 7FFEh 8000h 803Eh Attribute Memory Address Using Serial Eeprom Offsetname ISA and Pcmcia ModeTypesymbol Space BANK0 BANK1 BANK2 BANK3 BANK4 BANK5 Internal I/O Space Mapping BS2 BS1 BS0 BANK# Bank Select Register Offset Name Type Symbol READ/WRITE BSRHigh Byte LOW BS2 BS0 LOW Pade Forco Loop Txena Byte High Fdse EPH STP Fdupl MON Nocrc Byte Loop Sqet AUI Fdse Fduplx Ephloop Loop Loops AT Network Transmits LTX MUL High Link CTR EXC Lost Latcol Wakeu ByteOvrn Carr LOW LTX SqetPage Rxabort Rxovrnint High SoftStrip Rxen Byte RST CAR LOW Almul Prms Byte AbortPage FFH Memory Size Actual Memory Register Device Space BANK0 Offset Name Type Symbol Memory ConfigurationMCR Register READ/WRITE INT Byte High Full SET AUI Byte Wait StepSelec DIS INT SEL1 INT SEL0 Interrupt PIN Used RA15 RA14 A15 A14 A13Byte LOW ROM Size RA17 High Address Byte LOW High Byte LOW Byte High Data Byte LOW Data Byte High RCV Release LOW Eeprom Reload Store Byte EnableWakeu Auto Byte BAD Pcmcia Eeprom to Sram Memory Map 3FF 3FA3FC 3FD 000 0 Noop no Operation High Byte LOW Command N0/BUSCommand SET xyz Busy Bit Readable Command Sequencing Failed Allocated Packet Number This register is updated upon an Allocate Memory MMU commandPage Page Through Ah Space BANK2 Offset Name Type SymbolData Register READ/WRITE Data High Data LOW Ercv INT Rxovr Empty TX INT Ercv EPH INT Rxovr Alloc TX INT RCV INT EmptyPage INT LOW Multicast Table Byte High Bit MDO NXNDEIOS2 IOS1 IOS0 Byte LOW Mdoe Mclk MDI MDO MDOE=0 MDOE=1 Chip ID Value Device High Byte LOW Byte Chip REV Byte Discr High Byte LOW RCV Memory Architecture Theory of OperationFull Duplex Ethernet Support Main 802.3 section affected by Fdse is Behavior in Fdse Mode Typical Flow of Events for Transmit Driver CSMA/CD Side Typical Flow of Events for Receive Driver CSMA/CD Side Ethernet Interrupt Service Routine MMU RAM CSMA/CD RX Intr Assumes Auto Release Option Selected TX Intr Txempty Intr Driver Send and Allocate Routines Interrupt Generation Memory Partitioning Internal VS. External Attribute Memory MAP Attribute Memory Decodes Using Serial Eprom Ireq Pcmcia Configuration Registers DescriptionSreset Wrattri IOIs8 8002h Ethernet Configuration and Status Register EcsrPage Pcmcia functionality, this bit must be set LevIREQ Enable IOIs8 Reserved Audio Current Value Value Written NEW Value 8024h Pin Replacement Register PRR 8028h Extended Status RegisterESR Ringevent Ringenable A15 A14 A13 A12 A11 A10 802Ah Modem I/O Base Register 802Ch Modem I/O Base Register 8032h Modem I/O Size Register Memory Management Unit Functional Description of the BlocksArbiter Wait State Policy BUS Interface DMA Block Packet Number Fifos MMU Packet Number Flow and Relevant Registers DMA Csma Block Physical Interface Network Interface10BASE-T AUI Transmit Functions Receive Functions Page Register Address Board Setup Information ISA ModeEthernet Individual Address I/O Base Address Eeprom Word Arbitration Considerations Diagnostic LEDsPage 103 64 X 16 Serial Eeprom MAP for ISA Mode Operational Description Maximum Guaranteed RatingsParameter Symbo MIN TYP MAX Units Comments Type Buffer Input LeakageIP Type Buffers ID Type Buffers Limits Parameter Symbo MIN TYP MAX Unit Test Condition OD16 Type BufferOD162 Type Buffer OD24 Type Buffer Capacitive Load on Outputs Parameter MIN TYP MAX UnitsINTRO-INTR3 108 Timing DiagramsA50, nREG NCE1 NOE D150 30 max Max Min Data Valid NWE High NCE1 Low to nWE High Setup Address/nREG Setup Time to NWE Low109 110 O Read Timing Table on the following Parameter Min Typ Max Units 112 O Write Timing Table on the following 100 114 Card Configuration Registers READ/WRITE Pcmcia Mode A15=1 115 NINPAC 116 Consecutive Pcmcia Write Cycles 117 Pcmcia Attribute Memory READ/WRITE A15=0 118 Mringoutb 119 ISA Consecutive Read Cycles 120 ISA Consecutive Write Cycles 121 ISA Consecutive Read and Write Cycles 122 Data Register Special Read Access 123 Data Register Special Write Access 124 BIT Mode Register Cycles 125 ISA Register Access When Using Bale 126 External ROM Read Access Using Bale 127 Eeprom Read 128 Eeprom Write 129 Memory Read Timing 130 External Endec Interface Start of Transmit 131 Differential Output Signal Timing 10BASE-T and AUI Tperxpn Recp Recn Tperxp Tperxn Recp Recn 134 Transmit Timing END of Frame AUI and 10BASE-T 135 Collision Timing AUI 136 Vtqfp Package OutlinePage Kennedy Drive Hauppauge, NY 516 435-6000 FAX 516