LAN9220_12 Datasheet, PDF (60/151 Pages) SMSC Corporation – 16-bit Non-PCI Small Form Factor 10/100 Ethernet Controller with Variable Voltage I/O & HP Auto-MDIX Support

16-bit Non-PCI Small Form Factor 10/100 Ethernet Controller with Variable Voltage I/O & HP Auto-MDIX Support
Datasheet
Data Written to the
Ethernet Controller
TX Command 'A'
Buffer End Alignment = 1
Data Start Offset = 4
First Segment = 1
Last Segment = 0
Buffer Size = 4
31
0
TX Command 'A'
TX Command 'B'
4-Byte Data Start Offset
TX Command 'B'
TX Checksum Preamble
Packet Length = 115
TX Checksum Enable = 1
8-Byte End Padding
Checksum Preamble
TX Checksum Location = 50
TX Checksum Start Pointer = 14
TX Command 'A'
Buffer End Alignment = 1
Data Start Offset = 7
First Segment = 0
Last Segment = 0
Buffer Size = 79
TX Command 'B'
Packet Length = 115
TX Checksum Enable = 1
31
0
TX Command 'A'
TX Command 'B'
7-Byte Data Start Offset
79-Byte Payload
Pad DWORD 1
10-Byte
End Padding
31
TX Command 'A'
Buffer End Alignment = 1
Data Start Offset = 0
First Segment = 0
Last Segment = 0
Buffer Size = 15
TX Command 'B'
Packet Length = 115
TX Checksum Enable = 1
0
TX Command 'A'
TX Command 'B'
15-Byte Payload
1B
31
0
TX Command 'A'
Buffer End Alignment = 1
10-Byte
EnTdX OCfofmsemt Panaddd'Ain'g
Data Start Offset = 10
TX Command 'B'
First Segment = 0
Last Segment = 1
Buffer Size = 17
10-Byte
Data Start Offset
TX Command 'B'
Packet Length = 115
TX Checksum Enable = 1
17-Byte Payload Data
NOTE: When enabled, the TX Checksum
Preamble is pre-pended to data to be
transmitted. The FS bit in TX Command 'A', the
CK bit in TX Command 'B' and the TXCOE_EN
bit in the COE_CR register must all be set for
the TX checksum to be generated. FS must
not be set for subsequent fragments of the
same packet.
Data Passed to the
TX Data FIFO
TX Command 'A'
TX Command 'B'
TX Checksum Preamble
TX Command 'A'
79-Byte Payload
TX Command 'A'
15-Byte Payload
TX Command 'A'
17-Byte Payload
NOTE: Extra bytes
between buffers are
not transmitted
Revision 2.9 (03-01-12)
5-Byte End Padding
Figure 3.23 TX Example 3
60
DATASHEET
SMSC LAN9220