CS8900A
Crystal LAN™ ISA Ethernet Controller
5.2.1.3 Transfer............................................................................................................................ 81
5.2.2 Receive Configuration ............................................................................................................... 81
5.2.2.1 Configuring the Physical Interface.................................................................................... 81
5.2.2.2 Choosing which Frame Types to Accept..........................................................................81
5.2.2.3 Selecting which Events Cause Interrupts......................................................................... 82
5.2.2.4 Choosing How to Transfer Frames .................................................................................. 82
5.2.3 Receive Frame Pre-Processing................................................................................................. 83
5.2.3.1 Destination Address Filtering ........................................................................................... 83
5.2.3.2 Early Interrupt Generation................................................................................................ 84
5.2.3.3 Acceptance Filtering......................................................................................................... 84
5.2.3.4 Normal Interrupt Generation............................................................................................. 84
5.2.4 Held vs. DMAed Receive Frames..............................................................................................84
5.2.5 Buffering Held Receive Frames................................................................................................. 84
5.2.6 Transferring Held Receive Frames............................................................................................ 86
5.2.7 Receive Frame Visibility............................................................................................................. 86
5.2.8 Example of Memory Mode Receive Operation ..........................................................................86
5.2.9 Receive Frame Byte Counter..................................................................................................... 87
5.3 Receive Frame Address Filtering........................................................................................................ 87
5.3.0.1 Individual Address Frames............................................................................................... 88
5.3.0.2 Multicast Frames.............................................................................................................. 88
5.3.0.3 Broadcast Frames............................................................................................................ 88
5.3.1 Configuring the Destination Address Filter ................................................................................ 88
5.3.2 Hash Filter ................................................................................................................................. 89
5.3.2.1 Hash Filter Operation ....................................................................................................... 89
5.3.3 Broadcast Frame Hashing Exception ........................................................................................ 89
5.4 Receive DMA ...................................................................................................................................... 90
5.4.1 Overview.................................................................................................................................... 90
5.4.2 Configuring the CS8900A for DMA Operation ........................................................................... 90
5.4.3 DMA Receive Buffer Size .......................................................................................................... 90
5.4.4 Receive-DMA-Only Operation ................................................................................................... 91
5.4.5 Committing Buffer Space to a DMAed Frame............................................................................ 92
5.4.6 DMA Buffer Organization...........................................................................................................92
5.4.7 RxDMAFrame Bit....................................................................................................................... 92
5.4.8 Receive DMA Example Without Wrap-Around ..........................................................................92
5.4.9 Receive DMA Operation for RxDMA-Only Mode....................................................................... 92
5.5 Auto-Switch DMA ................................................................................................................................ 93
5.5.1 Overview.................................................................................................................................... 93
5.5.2 Configuring the CS8900A for Auto-Switch DMA........................................................................ 94
5.5.3 Auto-Switch DMA Operation...................................................................................................... 94
5.5.4 DMA Channel Speed vs. Missed Frames.................................................................................. 95
5.5.5 Exit From DMA........................................................................................................................... 95
5.5.6 Auto-Switch DMA Example........................................................................................................ 96
5.6 StreamTransfer ...................................................................................................................................96
5.6.1 Overview.................................................................................................................................... 96
5.6.2 Configuring the CS8900A for StreamTransfer........................................................................... 96
5.6.3 StreamTransfer Operation ......................................................................................................... 96
5.6.4 Keeping StreamTransfer Mode Active.......................................................................................96
5.6.5 Example of StreamTransfer....................................................................................................... 98
5.6.6 Receive DMA Summary............................................................................................................. 98
5.7 Transmit Operation..............................................................................................................................99
5.7.1 Overview.................................................................................................................................... 99
5.7.2 Transmit Configuration............................................................................................................... 99
5.7.2.1 Configuring the Physical Interface.................................................................................... 99
CIRRUS LOGIC PRODUCT DATA SHEET
DS271PP3
6
CIRRUS [ CIRRUS LOGIC ]
