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Fast Ethernet Controllers (FEC0 and FEC1)
Freescale Semiconductor
26-4
•
Retransmission from transmit FIFO following a collision (no processor bus utilization)
•
Automatic internal flushing of the receive FIFO for runts (collision fragments) and address
recognition rejects (no processor bus utilization)
•
Address recognition
— Frames with broadcast address may be always accepted or always rejected
— Exact match for single 48-bit individual (unicast) address
— Hash (64-bit hash) check of individual (unicast) addresses
— Hash (64-bit hash) check of group (multicast) addresses
— Promiscuous mode
26.2
Modes of Operation
The primary operational modes are described in this section.
26.2.1
Full and Half Duplex Operation
Full duplex mode is for use on point-to-point links between switches or end node to switch. Half duplex
mode works in connections between an end node and a repeater or between repeaters. TCR
n
[FDEN]
controls duplex mode selection.
When configured for full duplex mode, flow control may be enabled. Refer to the
TCR
n
[RFC_PAUSE,TFC_PAUSE] bits, the RCR
n
Section 26.5.11, “Full Duplex Flow
26.2.2
Interface Options
The following interface options are supported. A detailed discussion of the interface configurations is
provided in
Section 26.5.6, “Network Interface Options.”
26.2.2.1
10 Mbps and 100 Mbps MII Interface
The IEEE 802.3 standard defines the media independent interface (MII) for 10/100 Mbps operation. The
MAC-PHY interface may be configured to operate in MII mode by setting RCR
n
[MII_MODE].
FEC
n
_TXCLK and FEC
n
_RXCLK pins driven by the external transceiver determine the operation speed.
The transceiver auto-negotiates the speed or software controls it via the serial management interface
(FEC
n
_MDC/FEC
n
_MDIO pins) to the transceiver. Refer to the MMFR
n
and MSCR
n
register
descriptions, as well as the section on the MII, for a description of how to read and write registers in the
transceiver via this interface.
26.2.2.2
10 Mbps and 100 Mbps RMII Interface
The reduced media independent interface (RMII) is a low cost alternative to the IEEE 802.3 MII standard.
This interface provides the functionality of the MII interface on a total of 8 pins instead of 18. The RMII
interface for 10/100 Ethernet MAC-PHY interface was defined by an industry consortium and is not
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...