DP83256VF-AP NSC [National Semiconductor], DP83256VF-AP Datasheet - Page 5

• Manufacturer Part Number: DP83256VF-AP
• Manufacturer: NSC [National Semiconductor]

2 0 Architecture Description
2 1 BLOCK OVERVIEW
The PLAYER
Recovery Receiver Configuration Switch Transmitter Sta-
tion Management (SMT) Support and Clock Generation
Module as shown in Figure 2-1
Clock Recovery
The Clock Recovery Module accepts a 125 Mbps NRZI data
stream from the external PMD receiver It then provides the
extracted and synchronized data and clock to the Receiver
block
The Clock Recovery Module performs the following opera-
tions
Receiver
During normal operation the Receiver Block accepts serial
data as inputs at the rate of 125 Mbps from the Clock Re-
covery Module During the Internal Loopback mode of oper-
ation the Receiver Block accepts data directly from the
Transmitter Block
Locks to and tracks the incoming NRZI data stream
Extracts data stream and synchronized 125 MHz clock
a
device is comprised of six blocks Clock
FIGURE 2-1 PLAYER
a
5
Device Block Diagram
The Receiver Block performs the following operations
Configuration Switch
An FDDI station may be in one of three configurations Iso-
late Wrap or Thru The Configuration Switch supports these
configurations by switching the transmitted and received
data paths between PLAYER
MACSI devices
The configuration switch is integrated into the PLAYER
device therefore no external logic is required for this func-
tion
Setting the Configuration switch can be done explicitly via
the Control Bus Interface or it can be set automatically with
the CF React SMT Support feature
Optionally converts the incoming data stream from NRZI
to NRZ
Decodes the data from 5B to 4B coding
Converts the serial bit stream into 10-bit bytes composed
of 8 bits data 1 bit parity and 1 bit control information
Compensates for the differences between the upstream
station clock and the local clocks
Decodes Line States
Detects link errors
Presents data symbol pairs (bytes) to the Configuration
Switch Block
a
devices and one or more
TL F 11708– 2
a