LAN9118MT Standard Microsystems (SMSC), LAN9118MT Datasheet - Page 60

• Manufacturer Part Number: LAN9118MT
• Manufacturer: Standard Microsystems (SMSC)

Revision 1.0 (03-17-05)
4.12.5
Calculating Actual TX Data FIFO Usage
The following rules are used to calculate the actual TX data FIFO space consumed by a TX Packet:
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TX command 'A' is stored in the TX data FIFO for every TX buffer
TX command 'B' is written into the TX data FIFO when the First Segment (FS) bit is set in TX
command 'A'
Any DWORD-long data added as part of the “Data Start Offset” is removed from each buffer before
the data is written to the TX data FIFO. Any data that is less than 1 DWORD is passed to the TX
data FIFO.
Payload from each buffer within a Packet is written into the TX data FIFO.
Any DWORD-long data added as part of the End Padding is removed from each buffer before the
data is written to the TX data FIFO. Any end padding that is less than 1 DWORD is passed to the
TX data FIFO
DATASHEET
60
High-Performance Single-Chip 10/100 Non-PCI Ethernet Controller
SMSC LAN9118
Datasheet