Non-PCI Single-Chip Full Duplex Ethernet Controller with Magic Packet
FIGURE 9.1 - MMU PACKET NUMBER FLOW AND RELEVANT REGISTERS
9.8
CSMA Block
The CSMA/CD block is first interfaced via its control registers in order to define its operational
configuration. From then on, the DMA interface between the CSMA/CD block and memory is used to
transfer data to and from its data path interface.
For transmit, the CSMA/CD block will be asked to transmit frames as soon as they are ready in memory. It
will continue transmissions until any of the following transmit error occurs:
1. Collisions on same frame
2. Late collision
3. Lost Carrier sense and MON_CSN set
4. Transmit Underrun
5. SQET error and STP_SQET set
Rev. 09/10/2004
Page 84
SMSC LAN91C965v&3v
DATASHEET
SMSC [ SMSC CORPORATION ]
