2.0 Functional Description
CN8223
2.2 Line Framers
ATM Transmitter/Receiver with UTOPIA Interface
2.2.2 Internally Framed Receive Line Interface
In internal framer mode, the receiver inputs are positive and negative pulse
indications, and the receive clock (and NRZ serial data if internal B3ZS/HDB3
decoding is disabled) comes from an external LIU.
Table 2-4 lists the interface connections for all of the internal framing modes.
The functional timing for the receive line interface is similar for all internal
framer modes. Figure 2-5 illustrates the interface timing when the internal
B3ZS/HDB3 decoder is enabled. The RXPOS and RXNEG inputs are sampled on
the falling edge of the RXCKI clock input. Data inputs can be sampled on the
rising edge of the input clock by setting Invert RX Clock Sampling [bit 8] in
register CONFIG_3 [0x02].
Table 2-4. Internal Framer Receiver Interface Connections
Signal Name
Connect to CN8223 Pin
Receive Clock Input (RXCKI)
RXCKI
Receive Positive Data (RXPOS)
Receive Negative Data (RXNEG)
Receive Loss of Signal (RXLOS~~)
RXIN[1]
RXIN[2]
RXIN[4]
Figure 2-5. Internal Framer Receiver Interface Timing
RXCKI
RXPOS
RXNEG
2-6
Conexant
100046C
CONEXANT [ CONEXANT SYSTEMS, INC ]
