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CHAPTER 5 ETHERNET CONTROLLER
346
Preliminary User’s Manual S14767EJ1V0UM00
5.2.4 Detail of MAC control registers
5.2.4.1 En_MACC1-MAC Configuration Register 1 (00H R/W)
Bit
Field
Functions
Default
31:15
-
Reserved for future use. Write as 0
-
14
MACLB
MAC loopback:
Setting this bit to 1 switches into loopback mode which routes from Transmit Function Block
to Receive Function Block.
0
13:12
-
Reserved for future use. Write as 0
-
11
TXFC
Transmit flow control enable:
Setting this bit to 1 enables to transmit the pause control frame.
0
10
RXFC
Receive flow control enable:
Setting this bit to 0 enables MAC to execute PAUSE operation for the pause time on the
setting of the pause timer. The setting of the pause timer must be updated every time a valid
PAUSE control frame is received regardless of the setting of this bit.
0
9
SRXEN
Receive enable:
Setting this bit to 1 enables the function of the MAC Address field filtering.
0
8
PARF
Control packet pass:
Setting this bit to 1 allows MAC to check for all received packets including control frames.
When this bit is set to 0, MAC does not check the reception of a control frame.
0
7
PUREP
Pure preamble:
Setting this bit to 1 allows the recognition of start of a new packet only when a pure
preamble ( “0101” only ) is seen.
0
6
FLCHT
Length field check:
When this bit is set to 1, MAC compares the length field value in the packet to the actual
packet length, and indicates the result in the status vector. When this bit is set 0, MAC does
not check the Frame length field.
0
5
NOBO
No Back Off:
When this bit is set to 1, MAC always transmits the packet with no backoff operation.
0
4
-
Reserved for future use. Write as 0
-
3
CRCEN
CRC append enable:
Setting this bit to 1 enables MAC to append calculated CRC code to the end of transmitted
packet automatically.
0
2
PADEN
PAD append enable:
Setting this bit to 1 enables MAC to append PAD when the transmitted packet length is less
than 64 octets because the input data (TPD) length is less than 60 bytes before appending
the CRC.
0
1
FULLD
Full duplex enable:
Setting this bit to 1 enables the full duplex operation.
0
0
HUGEN
Large packet enable:
Setting this bit to 1 enable MAC to transmit and receive a packet of which length is over the
value of En_LMAX register.
0