Datasheet

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O
Datasheet
SMSC LAN9221/LAN9221i 97 Revision 2.9 (03-01-12)
DATASHEET
5.3.16 GPT_CNT-General Purpose Timer Current Count Register
This register reflects the current value of the GP Timer.
5.3.17 WORD_SWAP—Word Swap Control
This register controls how words from the host data bus are mapped to the CSRs and Data FIFOs
inside the LAN9221/LAN9221i. The LAN9221/LAN9221i always sends data from the Transmit Data
FIFO to the network so that the low order word is sent first, and always receives data from the network
to the Receive Data FIFO so that the low order word is received first.
Offset: 90h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31-16 Reserved RO -
15-0 General Purpose Timer Current Count (GPT_CNT). This 16-bit field
reflects the current value of the GP Timer.
RO FFFFh
Offset: 98h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Word Swap. If this field is set to 00000000h, or anything except
0xFFFFFFFFh, the LAN9221/LAN9221i maps words with address bit A[1]=1
to the high order words of the CSRs and Data FIFOs, and words with
address bit A[1]=0 to the low order words of the CSRs and Data FIFOs. If
this field is set to 0xFFFFFFFFh, the LAN9221/LAN9221i maps words with
address bit A[1]=1 to the low order words of the CSRs and Data FIFOs, and
words with address bit A[1]=0 to the high order words of the CSRs and Data
FIFOs.
Note: Word swap is used in conjunction with the mixed endian
functionality to determine the final byte ordering. Refer to Section
3.7.3, "Mixed Endian Support" for more information.
R/W
NASR
00000000h