CN8223 Datasheet, PDF (38/161 Pages) Conexant Systems, Inc – ATM Transmitter/Receiver with UTOPIA Interface

2.0 Functional Description
2.2 Line Framers
CN8223
ATM Transmitter/Receiver with UTOPIA Interface
2.2.1 Internally Framed Transmit Line Interface
In internal framer mode, the transmitter provides positive and negative pulse
indications and a transmit output clock to an external Line Interface Unit (LIU)
(or output clock and NRZ serial data if internal B3ZS/HDB3 encoding is
disabled) in response to a transmit input clock.
Table 2-2 gives the internal framing mode interface connections. The
functional timing for the transmit line interface is similar for all internal framer
modes. Figure 2-3 illustrates the interface timing when the internal B3ZS/HDB3
encoder is enabled. The TCLKO phase shown can be inverted with Invert TX
Clock Output [bit 7] of the CONFIG_3 register [0x02].
Table 2-2. Internal Framer Transmitter Interface Connections
Signal Name
Connect to CN8223 Pin
Transmit Clock Input (TXCKI)
Transmit Clock Output (TCLKO)
Transmit Positive Data (TXPOS)
Transmit Negative Data (TXNEG)
TXCKI
TCLKO
TXOUT[1]
TXOUT[2]
Figure 2-3. Internal Framer Transmitter Interface Timing with Line Encoding
TCLKO
TXPOS
TXNEG
2-4
Conexant
100046C