dp83630sqx National Semiconductor Corporation, dp83630sqx Datasheet - Page 30
dp83630sqx
Manufacturer Part Number
dp83630sqx
Description
Precision Phyter - Ieee 1588 Precision Time Protocol Transceiver
Manufacturer
National Semiconductor Corporation
Datasheet
1.DP83630SQX.pdf
(126 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
dp83630sqx/NOPB
Manufacturer:
Texas Instruments
Quantity:
10 000
- Current page: 30 of 126
- Download datasheet (3Mb)
www.national.com
11.1.1 Code-Group Encoding and Injection
The code-group encoder converts 4-bit (4B) nibble data gen-
erated by the MAC into 5-bit (5B) code-groups for transmis-
sion. This conversion is required to allow control data to be
combined with packet data code-groups. Refer to
4B to 5B code-group mapping details.
The code-group encoder substitutes the first 8-bits of the
MAC preamble with a J/K code-group pair (11000 10001) up-
on transmission. The code-group encoder continues to re-
place subsequent 4B preamble and data nibbles with
corresponding 5B code-groups. At the end of the transmit
packet, upon the deassertion of Transmit Enable signal from
the MAC, the code-group encoder injects the T/R code-group
pair (01101 00111) indicating the end of the frame.
DATA CODES
IDLE AND CONTROL CODES
INVALID CODES
Note: Control code-groups I, J, K, T and R in data fields will be mapped as invalid codes, together with RX_ER asserted.
Name
C
D
H
R
A
B
E
F
K
T
V
V
V
V
V
V
V
V
V
V
0
1
2
3
4
5
6
7
8
9
J
I
TABLE 8. 4B5B Code-Group Encoding/Decoding
PCS 5B Code-Group
11110
01001
10100
10101
01010
01011
01110
01111
10010
10011
10110
10111
11010
11011
11100
11101
00100
11111
11000
10001
01101
00111
00000
00001
00010
00011
00101
00110
01000
01100
10000
11001
Table 8
for
30
HALT code-group - Error code
Inter-Packet IDLE - 0000 (See Note)
First Start of Packet - 0101 (See Note)
Second Start of Packet - 0101 (See Note)
First End of Packet - 0000 (See Note)
Second End of Packet - 0000 (See Note)
After the T/R code-group pair, the code-group encoder con-
tinuously injects IDLEs into the transmit data stream until the
next transmit packet is detected (reassertion of Transmit En-
able).
11.1.2 Scrambler
The scrambler is required to control the radiated emissions at
the media connector and on the twisted pair cable (for
100BASE-TX applications). By scrambling the data, the total
energy launched onto the cable is randomly distributed over
a wide frequency range. Without the scrambler, energy levels
at the PMD and on the cable could peak beyond FCC limita-
tions at frequencies related to repeating 5B sequences (i.e.,
continuous transmission of IDLEs).
MII 4B Nibble Code
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Related parts for dp83630sqx
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Freescale Semiconductor Technical Data
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Self-calibrating 12-bit Plus Sign Serial I/o A/d Converters With Mux And Sample/hold
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Pllatinum Tm Fractional N Rf / Integer N If Dual Low Power Frequency Synthesizer
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Pllatinum? 2.0 Ghz Frequency Synthesizer For Rf Personal Communications
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Pllatinumtm 160 Mhz Frequency Synthesizer For Rf Personal Communications
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Dual N-channel Enhancement Mode Field Effect Transistor
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Video Amplifier System (obsolete)
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Synchronous Step-up DC/DC Converter For White Led Applications
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
CLC420 - High Speed, Voltage Feedback op Amp, Package: Lcc, Pin Nb=20
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Monolithic Triple 4.5 CRT Driver
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Differential Video Amplifier
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
ADC10061 - 10-Bit 600 NS A/D Converter With Input Multiplexer And Sample/Hold, Package: Soic Wide, Pin Nb=20
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
DS36277 - Dominant Mode Multipoint Transceiver, Package: Soic Narrow, Pin Nb=8
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Printer Solenoid Driver
Manufacturer:
National Semiconductor Corporation
Datasheet:
Part Number:
Description:
Quad High Speed Trapezoidal Bus Transceiver
Manufacturer:
National Semiconductor Corporation
Datasheet: