Cirrus-logic CS8900A Manuel d'utilisateur Page 1

Copyright  Cirrus Logic, Inc. 2010(All Rights Reserved)CS8900AProduct Data SheetCrystal LAN™ Ethernet ControllerFEATURES Single-Chip IEEE 802.3 Ethe

10 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET• On-chip LED ports can be used for eitheroptional LEDs, or as programm

100 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETthe LineCTL register (Register 13) and is de-scribed in Table 31. No

DS271F5 101CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.6.4 Enabling CRC Generation and Pad-dingWhenever the host issues a

102 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET1) The host bids for frame storage by writingthe Transmit Command to t

DS271F5 103CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.6.8 Completing TransmissionWhen the CS8900A successfully completest

104 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.6.9 Rdy4TxNOW vs. Rdy4TxThe Rdy4TxNOW bit (Register 18, BusST, bit8

DS271F5 105CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETnot set). Also, the Rdy4Tx bit is used with in-terrupts and requires t

106 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETCS8900A may not auto-select the 10BASE-Tmedia. The cause of this situa

DS271F5 107CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET6.0 TEST6.1 TEST MODES6.1.1 Loopback & Collision Diagnostic Tes

108 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET6.2 Boundary ScanBoundary Scan test mode provides an easyand efficien

DS271F5 109CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETThe input pins not included in this test are:After the Input Cycle is

DS271F5 11CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETEECSEEDATAOUTEESKSA[0:19]MEMWMEMRIOWIORREFRESHSBHESD[0:15]INTRQ0INTRQ1R

110 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETENTER BOUNDARY SCAN:CS8900A resets, all digitaloutput pins and bi-dire

DS271F5 111CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETTESTSELAENOutputsAll outputstri-stateLANLEDlowBSTATUSlowEEDataOutRESET

112 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET7.0 CHARACTERISTICS/SPECIFICATIONS - COMMERCIAL7.1 ABSOLUTE MAXIMUM

DS271F5 113CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETDC CHARACTERISTICS (Continued)Notes: 2. OD24: Open Drain Output with

114 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET7.4 SWITCHING CHARACTERISTICS (TA = 25 °C; VDD = 5.0 V or VDD = 3.3V)

DS271F5 115CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

116 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

DS271F5 117CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

118 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

DS271F5 119CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

12 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET2.0 PIN DESCRIPTION 364041464748495026272829303133323435373839424

120 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

DS271F5 121CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET7.5 10BASE-T WIRING• If a center tap transformer is used on the RXD+

122 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET7.6 AUI WIRING 7.7 QUARTZ CRYSTAL REQUIREMENTS (If a 20 MHz quartz

DS271F5 123CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET8.0 CHARACTERISTICS/SPECIFICATIONS - INDUSTRIAL8.1 ABSOLUTE MAXIMUM

124 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETDC CHARACTERISTICS (Continued)Notes: 2. OD24: Open Drain Output with

DS271F5 125CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET8.4 SWITCHING CHARACTERISTICS (TA = 25 °C; VDD = 5.0 V or VDD = 3.3V)

126 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

DS271F5 127CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

128 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

DS271F5 129CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

DS271F5 13CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETISA Bus InterfaceSA[0:19] - System Address Bus, Input PINS 37-48, 50-54

130 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

DS271F5 131CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETSWITCHING CHARACTERISTICS (Continued)Parameter Symbol Min Typ Max Unit

132 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET8.5 10BASE-T WIRING• If a center tap transformer is used on the RXD+

DS271F5 133CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET8.6 AUI WIRING 8.7 QUARTZ CRYSTAL REQUIREMENTS (If a 20 MHz quartz

134 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET9.0 PHYSICAL DIMENSIONS MILLIMETERSDIM MIN NOM MAXA --- 1.60A1 0.05

DS271F5 135CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET10.0 GLOSSARY OF TERMS10.1 AcronymsAUI Attachment Unit InterfaceCRC

136 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET10.2 DefinitionsCyclic Redundancy CheckThe method used to compute the

DS271F5 137CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET10.3 Acronyms Specific to the CS8900ABufCFG Buffer Configuration - Re

138 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETStandbyA feature of the CS8900A used to conserve power. When in Standb

14 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETIOW - I/O Write, Input PIN 62. When IOW is low and a valid address is d

DS271F5 15CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETEECS - EEPROM Chip Select, PIN 3.Active-high output used to select the

16 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETGeneral Pins XTAL[1:2] - Crystal, Input/Output PINS 97 and 98.A 20 M

DS271F5 17CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET3.0 FUNCTIONAL DESCRIPTION3.1 OverviewDuring normal operation, the CS

18 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETas Memory space operations, I/O space oper-ations, or as DMA operations

DS271F5 19CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETmemory. The CS8900A has three pairs ofDMA pins that can be connected di

2 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETTABLE OF CONTENTS1.0 INTRODUCTION ...

20 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET3.3.2 Allowing Time for Reset OperationAfter a reset, the CS8900A goes

DS271F5 21CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET 3.4 Configurations with EEPROM3.4.1 EEPROM InterfaceThe interface t

22 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETthe EEPROM). Address space 80h to AFh isreserved.3.4.3.1 Reset Configu

DS271F5 23CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETbytes of configuration data are stored in theReset Configuration Block.

24 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETBits 8 through 0 of the Group Header specify a9-bit PacketPage Address.

DS271F5 25CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETinitialization is complete (configuration loadedfrom EEPROM or reset to

26 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET(for a ’C56, ’CS56, ’C66 or ’CS66), are shiftedout of the CS8900A, into

DS271F5 27CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETand the Address Mask is FC000h. This config-uration describes a 16-Kbyt

28 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET8). To exit SW Suspend, the host must write tothe CS8900A’s assigned I/

DS271F5 29CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET3.8 LED OutputsThe CS8900A provides three output pins thatcan be used

DS271F5 3CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET3.4.7.1 Determining EEPROM Size ...

30 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETcollision detection, preamble generation anddetection, and CRC generati

DS271F5 31CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETtire packet has been received, the MAC vali-dates the FCS. If an error

32 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETnetwork collisions. The collision count isstored in bits B through E of

DS271F5 33CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETattempting transmission. The CS8900A sup-ports two schemes for determin

34 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET3.9.5.4 Collision ResolutionIf a collision is detected while the CS890

DS271F5 35CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETbit times), and k is the smaller of n or 10, wheren is the number of re

36 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET40% and 60%. The specifications for the crys-tal are described in Secti

DS271F5 37CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET3.11.1 10BASE-T FiltersThe CS8900A’s 10BASE-T transceiver in-cludes in

38 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETsquelch threshold (either positive or negative,depending on polarity) i

DS271F5 39CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETat least four frames in a row with negative po-larity after the EOF, th

4 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET3.10.4 Interface Selection ...

40 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET3.13 External Clock OscillatorA 20-MHz quartz crystal or CMOS clock in

DS271F5 41CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.0 PACKETPAGE ARCHITECTURE4.1 PacketPage OverviewThe CS8900A archite

42 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETto and from the host. The host simply writes toand reads from these loc

DS271F5 43CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET0100h 32 Read/Write Configuration & Control Registers (2 bytes per

44 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.3 Bus Interface Registers4.3.1 Product Identification Code(Read onl

DS271F5 45CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETing bus signals are tied to the following pins: See Section 3.2 on pag

46 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETReset value is: 0000 0000 0000 0000 4.3.6 DMA Frame Count(Read only,

DS271F5 47CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETThe lower three bytes (0030h, 0031h, and 0032h) of the Boot PROM Base A

48 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETReset value is: XXXX XXXX XXXX XXXX 4.3.12 EEPROM Data(Read/Write, A

DS271F5 49CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.4 Status and Control RegistersThe Status and Control registers are t

DS271F5 5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.10.2 TxCMD Port ...

50 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETtometer useful in locating cable faults. Thefollowing sections contain

DS271F5 51CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.4.3.4 Accept BitsThere are nine Accept bits located in the Rx-CTL re

52 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET Control and Configuration Bits RegisterFEDCBA9 876Number (Offs

DS271F5 53CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.4.5 Register 0: Interrupt Status Queue(ISQ, Read-only, Address: Pack

54 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETRegNum The lower six bits describe which register (4, 8, C, 10 or 12) i

DS271F5 55CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.4.7 Register 4: Receiver Event (RxEvent, Read-only, Address: Packe

56 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.4.8 Register 5: Receiver Control(RxCTL, Read/Write, Address: Packe

DS271F5 57CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.4.9 Register 7: Transmit Configuration(TxCFG, Read/Write, Address:

58 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET001000 These bits provide an internal address used by the CS8900A to id

DS271F5 59CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETBit 7 Bit 6 0 0 Start transmission after 5 bytes are in

6 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.4.1 Overview ...

60 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEEThost still wants to transmit that particular frame, the host must go th

DS271F5 61CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETTxUnderrun This bit is set if CS8900A runs out of data before it reache

62 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETCFG, Bit C) is set, there is an interrupt when TxCOL increments from 1F

DS271F5 63CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET2-partDefDis Before a transmission can begin, the CS8900A follows a def

64 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.4.18 Register 15: Self Control(SelfCTL, Read/Write, Address: Packe

DS271F5 65CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.4.19 Register 16: Self Status(SelfST, Read-only, Address: PacketPa

66 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETResetRxDMA When set, the RxDMA offset pointer at PacketPage base + 0026

DS271F5 67CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETRegister. When reading this register, these bits will be 011000, where

68 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETDisable Backoff When set, the backoff algorithm is disabled. The CS8900

DS271F5 69CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.5 Initiate Transmit Registers4.5.1 Transmit Command Request - TxCMD

DS271F5 7CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETTable 1. Revision History Release Date ChangesPP1 NOV 1997 Preliminary R

70 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETCMD, the length of the transmitted frame is written into this register.

DS271F5 71CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.6 Address Filter Registers4.6.1 Logical Address Filter (hash table)

72 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET4.7 Receive and Transmit Frame LocationsThe Receive and Transmit Frame

DS271F5 73CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETbyte address must be followed by a byteaccess to an odd-byte address be

74 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET• The address on the ISA System Addressbus (SA0 - SA19) is within the M

DS271F5 75CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETcan be written. If clear, the host must waitfor CS8900A buffer memory t

76 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETeration. The Transmit Command tells theCS8900A that the host has a fram

DS271F5 77CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETbase + 000Ch). If Rdy4TxNOW is set, theframe can be written. If clear,

78 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.0 OPERATION5.1 Managing Interrupts and Servicing the Interrupt Stat

DS271F5 79CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETAn enabled interrupt occurs.The selected interruptrequest pin is driven

8 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET1.0 INTRODUCTION1.1 General DescriptionThe CS8900A is a true single-ch

80 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETmemory via host DMA. This section describesreceive frame pre-processing

DS271F5 81CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.2.2.1 Configuring the Physical InterfaceConfiguring the physical int

82 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETmine how frames will be transferred to hostmemory, as described in Tabl

DS271F5 83CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETtecting the incoming frame's End-of-Frame(EOF) sequence.Like all E

84 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETEOFReceived?128 bytesReceived?EOFReceived?64 bytesReceived?EOFReceived?

DS271F5 85CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETThis section describes buffering and transfer-ring held receive frames.

86 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.2.8 Example of Memory Mode Receive OperationA common length for shor

DS271F5 87CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETregister can be read to determine the finalframe status.The sequence is

88 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETThe IAHashA, MulticastA, IndividualA, andBroadcastA bits are used indep

DS271F5 89CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.2.13 Broadcast Frame Hashing Excep-tionTable 26 describes in detail

DS271F5 9CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEEThigh level of integration allow System Engi-neers to design a complete E

90 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.3 Receive DMA5.3.1 OverviewThe CS8900A supports a direct interface

DS271F5 91CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.3.3 DMA Receive Buffer SizeIn receive DMA mode, the CS8900A stores r

92 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETNote that when in DMA mode, reading the con-tents of the RxEvent regist

DS271F5 93CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETbe completely received. Usually, the DMA re-ceive frame interrupt (RxDM

94 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.4 Auto-Switch DMA5.4.1 OverviewThe CS8900A supports a unique featur

DS271F5 95CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETered as normal. If there isn't, the CS8900A'sMAC engine compa

96 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETcoming frame also large, the incoming framemay be missed, depending on

DS271F5 97CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEETFrame 1Frame 2Frame 3 starts to be received and passes the DA filter.Th

98 DS271F5CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET• updates the DMA Start-of-Frame register(PacketPage base + 0026h);• up

DS271F5 99CS8900ACrystal LAN™ Ethernet ControllerCIRRUS LOGIC PRODUCT DATASHEET5.5.6 Receive DMA SummaryTable 30 summarize the Receive DMA config-ura