MTD800 データシートの表示（PDF） - Myson Century Inc

部品番号

コンポーネント説明

一致するリスト

MTD800

Integrated Fast Ethernet Controller

Myson Century Inc 

MYSON

TECHNOLOGY

MTD 800

(Preliminary)

Bit

Symbol

Descr iption

7

ES

Error Summary: This bit is set to 1 for receive error, the errors include the

following

- Runt packet Error (RUNT),

- Long packet Error (LONG) ,

- Frame Alignment Error (FAE),

- CRC Error (CRC), and

- Receive coding Error (RXER).

6

RUNT

Runt Packet Received : When set, indicates the MTD800 receives a

packet whose length is less than 64 bytes.

5

LONG

Long Packet Received : When set, indicates that the received frame

length exceeds the maximum Ethernet-specified size of 1518 bytes.

4

FAE

Frame Align Error : When set, indicates that the received frame has an

alignment Error.

3

CRC

CRC Error : When set, indicates a CRC error occurred on the received

frame.

2

RXER

Receive Error : When set, indicates a receive coding error occurred on

the received frame.

1-0

-

Reserved

Table 3.4 Receive Descriptor 1 (RDES1)

Bit

31 - 11

10 - 0

Symbol

-

RBS

Descr iption

Reserved

Receive buffer size : Receive buffer size for this descriptor, the size is

measured in bytes. The buffer size must be a multiple of 4.

3.4 Network Interface and MAC Protocol Handler

The network interface for transmit and receive function are both in a format of MII and ready for the intercon-

nection to PHY chip. The MTD800 defines a simple and efficient protocol for transforming the FIFO data back

and forth to a nibble-stream that is directly connected to MII. Meanwhile, the built-in Media Access Controller

(MAC), which is compliant to IEEE 802.3, performs the following functions ;

(i) transmit function : encapsulates the nibble-stream coming from transmit DMA with preambles, Start Frame

Delimiter (SFD), the frame check sequence and the padding zeroes if necessary;

(ii) receive function : delimits the incoming packet , extracts the destination address for recognition and

checks frame validation before transferring data onto the internal receive FIFO;

(iii) CSMA/CD function : executes the listening before transmission, makes sure 96-bit time for interframe

gap , detects collision and enforces the event by issuing jam pattern, enters into backoff state after

collision and waits for retransmission .

The MAC of the MTD800 also supports full-duplex function and IEEE 802.3x flow control protocol. If the

incoming packet with the predefined flow control destination address ( .i.e. 01-80-c2-00-00-01 ) and length/

10/42

MTD800 Revision 0.0 07/20/1999

Share Link: