Fast Ethernet Controller
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
35-22 Freescale Semiconductor

Figure 35-7. Ethernet Interrupt Events Example

NOTE

The FCC status register is not valid for the Ethernet protocol. The current

state of the MII signals can be read through the parallel ports.

35.19 Ethernet RxBDs

The Ethernet controller uses the RxBD to report information about the received data for each buffer.

Figure 35-8 shows the FCC Ethernet RxBD format.

RXB
Line Idle
Stored in Rx Buffer
RXD
RX_DV
Frame
Received in Ethernet
Time
Line Idle
TXD
TX_EN
Frame
Transmitted by Ethernet
COL
TXB, GRATXB
Line Idle Line Idle
Stored in Tx Buffer
Notes:
Ethernet FCCE
Events
1. RXB event assumes receive buffers are 64 bytes each.
2. The RXF interrupt may occur later than RX_DV due to receive FIFO latency.
Notes:
Ethernet FCCE
Events
1. TXB events assume the frame required two transmit buffers.
2. The GRA event assumes a graceful stop transmit command was issued during frame transmission.
PSFDDASA CR
RXF
T/L D
PSFDDASA CRT/L D
Legend:
P = Preamble, SFD = Start frame delimiter, DA and SA = Destination/Source address,
T/L = Type/Length, D = Data, CR = CRC bytes