LAN9211_0711 SMSC [SMSC Corporation], LAN9211_0711 Datasheet - Page 49

• Manufacturer Part Number: LAN9211_0711
• Description: High-Performance Small Form Factor Single-Chip Ethernet Controller with HP Auto-MDIX
• Manufacturer: SMSC [SMSC Corporation]

High-Performance Small Form Factor Single-Chip Ethernet Controller with HP Auto-MDIX
Datasheet
SMSC
3.12.1
LAN9211
TX Buffer Format
TX buffers exist in the host’s memory in a given format. The host writes a TX command word into the
TX data buffer before moving the Ethernet packet data. The TX command A and command B are 32-
bit values that are used by the LAN9211 in the handling and processing of the associated Ethernet
packet data buffer. Buffer alignment, segmentation and other packet processing parameters are
included in the command structure. The following diagram illustrates the buffer format.
Last Buffer in
Figure 3.13 Simplified Host TX Flow Diagram
Packet
DATASHEET
Command
(optional)
available
Padding
Check
space
Buffer
Write
Write
Write
FIFO
Start
Idle
init
TX
49
TX Status
Available
Not Last Buffer
(optional)
Read TX
Status
Revision 1.93 (11-27-07)