LAN9215I_07 Datasheet, PDF (53/138 Pages) SMSC Corporation – Highly Efficient Single-Chip 10/100 Ethernet Controller with HP Auto-MDIX and Industrial Temperature Support

Highly Efficient Single-Chip 10/100 Ethernet Controller with HP Auto-MDIX and Industrial Temperature Support
Datasheet
Figure 3.14, "TX Example 1" illustrates the TX command structure for this example, and also shows
how data is passed to the TX data FIFO.
Note 3.15 The LAN9215i host bus interface supports 16-bit bus transfers; internally, all data paths
are 32-bits wide. Figure 3.14 and Figure 3.15 describe the host write ordering for pairs of
atomic 16-bit transactions.
Data Written to the
Ethernet Controller
31
0
TX Com m and 'A'
Buffer End Alignment = 1
TXCommand'A'
Data Start Offset = 7
First Segment = 1
TXCommand'B'
Last Segment = 0
Buffer Size = 79
7-Byte Data Start Offset
TX Com m and 'B'
Packet Length = 111
Data Passed to the
TX Data FIFO
TXCommand'A'
TXCommand'B'
79-BytePayload
Pad DWORD 1
10-Byte
EndPadding
31
TX Com m and 'A'
Buffer End Alignment = 1
Data Start Offset = 0
First Segment = 0
Last Segment = 0
Buffer Size = 15
TX Com m and 'B'
Packet Length = 111
0
TXCommand'A'
TXCommand'B'
15-BytePayload
1B
31
0
TX Com m and 'A'
Buffer End Alignment = 1
10-Byte
ETnXdOCoffmsemtPaanddd'iAn'g
Data Start Offset = 10
TXCommand'B'
First Segment = 0
Last Segment = 1
10-Byte
Buffer Size = 17
Data Start Offset
TX Com m and 'B'
Packet Length = 111
17-BytePayloadData
79-BytePayload
TXCommand'A'
15-BytePayload
TXCommand'A'
17-BytePayload
NOTE: Extra bytes
betw een buffers are
not transmitted
SMSC LAN9215i
5-ByteEndPadding
Figure 3.14 TX Example 1
53
DATASHEET
Revision 1.93 (12-12-07)