K60P100M100SF2RM Datasheet, PDF (1229/1809 Pages) Freescale Semiconductor, Inc – K60 Sub-Family Reference Manual

Chapter 44 10/100-Mbps Ethernet MAC (ENET)
The preamble appears (RXD[1:0]=01) and the MACs begin capturing data following
detection of SFD.
RMII_REF_CLK
RMII_CRS_DV
RMII_RXD1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 x x x x x x 0
RMII_RXD0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 x x x x x x 0
/J/
/K /
Pream bl e
SFD
D ata
Figure 44-69. RMII receive operation
If a false carrier is detected (bad SSD), then RXD[1:0] is 10b until the end of the receive
event. This is a unique pattern since a false carrier can only occur at the beginning of a
packet where the preamble is decoded (RXD[1:0] = 01b).
RMII_REF_CLK
RMII_CRS_DV
RMII_RXD1
RMII_RXD0
000001111111111111110
000000000000000000000
False carrier detected
Figure 44-70. RMII receive operation with false carrier
In RMII transmit mode, TXD[1:0] provides valid data for each REF_CLK period while
TXEN is asserted.
RMII_REF_CLK
RMII_TXEN
RMII_TXD1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 x x x x x x 0
RMII_TXD0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 x x x x x x 0
Pream bl e
SFD
D ata
Figure 44-71. RMII transmit operation
K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc.
1229