CN8223
1.0 Product Description
ATM Transmitter/Receiver with UTOPIA Interface
1.3 Line Framing Functions
1.3 Line Framing Functions
The CN8223 provides framers for DS3, E3 (both G.751 and G.832), E4 (G.832),
STS-1, and STS-3c/STM-1 formatted serial streams. The line receive circuitry
recovers the frame location from the serial stream and provides cell octets to the
physical layer block for cell delineation. The transmit circuitry receives cell octets
from the cell generation or physical layer blocks and adds line framing overhead
information as required. The LIU receive interface detects both Loss-of-Signal
(LOS) and Line Code Violations (LCVs). The active edge of the transmit output
clock is selectable. Figure 1-2 illustrates the line framer functions of the CN8223.
Figure 1-2. Line Framer Diagram
TMRKR
TOVH_CLK TXOVH
8
Line
Interfaces
TCLKO_HS
TXOUT_HS
TXCKI_HS
RXCKI_HS
RXIN_HS
Tx
Overhead
Insert
Tx
HDLC
Tx
FEAC
High
Speed
DS3, E3, E4, STS-1
STS-3c, STM-1
Transmit Framer
TCLKO
TXOUT
TXCKI
RXCKI
RXIN
Medium
Speed
CN8223
Cell
Processing
RCV_HLD
LOCD
DS3, E3, E4, STS-1
STS-3c, STM-1
Receive Framer
9
9
Parallel
Interface
TXOUT[7:0]
RXIN[7:0]
Rx
Overhead
Extract
Rx
HDLC
Rx
FEAC
8
RMRKR
ROVH_CLK
RXOVH
CN8223 line framing functions include the following:
•
•
•
•
•
•
•
•
•
STS-1, STS-3c, STM-1, DS3, E3, E4, TAXI
External framer interface
Parallel interface
Unframed serial interface
HDB3/B3ZS encode/decode
Line overhead insertion/extraction
SONET scrambling
Error insertion
Alarm detection/generation
100046C
Conexant
1-5
CONEXANT [ CONEXANT SYSTEMS, INC ]
