LAN9252SLASHML datasheet(122/329 Pages) MICROCHIP

122 / 329 page

LAN9252

DS00001909A-page 122

 2015 Microchip Technology Inc.

11.2.2.2

4B/5B Encoder

The transmit data passes from the MII block to the 4B/5B Encoder. This block encodes the data from 4-bit nibbles to 5-

bit symbols (known as “code-groups”) according to Table 11-1. Each 4-bit data-nibble is mapped to 16 of the 32 possible

code-groups. The remaining 16 code-groups are either used for control information or are not valid.

The first 16 code-groups are referred to by the hexadecimal values of their corresponding data nibbles, 0 through F. The

remaining code-groups are given letter designations with slashes on either side. For example, an IDLE code-group is /

I/, a transmit error code-group is /H/, etc.

TABLE 11-1:

4B/5B CODE TABLE

Code Group

Sym

Receiver Interpretation

Transmitter Interpretation

11110

0000

DATA

0000

DATA

01001

0001

10100

0010

10101

0011

01010

0100

01011

0101

01110

0110

01111

0111

10010

1000

10011

1001

10110

1010

10111

1011

11010

1100

11011

1101

11100

1110

11101

1111

11111

/I/

IDLE

Sent after /T/R/ until the MII Transmitter

Enable signal (TXEN) is received

11000

/J/

First nibble of SSD, translated to “0101”

following IDLE, else MII Receive Error

(RXER)

Sent for rising MII Transmitter Enable

signal (TXEN)

10001

/K/

Second nibble of SSD, translated to

“0101” following J, else MII Receive Error

(RXER)

Sent for rising MII Transmitter Enable

signal (TXEN)

01101

/T/

First nibble of ESD, causes de-assertion

of CRS if followed by /R/, else assertion

of MII Receive Error (RXER)

Sent for falling MII Transmitter Enable

signal (TXEN)

00111

/R/

Second nibble of ESD, causes de-asser-

tion of CRS if following /T/, else assertion

of MII Receive Error (RXER)

Sent for falling MII Transmitter Enable

signal (TXEN)

00100

/H/

Transmit Error Symbol

Sent for rising MII Transmit Error (TXER)

LAN9252/ML 数据表(PDF) 122 Page - Microchip Technology

LAN9252/ML 数据表(HTML) 122 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载

链接网址

LAN9252/ML 数据表(PDF) 122 Page - Microchip Technology

LAN9252/ML 数据表(HTML) 122 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表 下载

链接网址

数据表下载