CN8223 Datasheet, PDF (120/161 Pages) Conexant Systems, Inc – ATM Transmitter/Receiver with UTOPIA Interface

3.0 Registers
3.7 Status Register Overview
CN8223
ATM Transmitter/Receiver with UTOPIA Interface
Table 3-16 lists definitions for External Framer, 57-Octet Mode, LINE_STATUS bits.
Table 3-16. External Framer, 57-Octet Mode, LINE_STATUS Bit Definitions
Bit
Ext. Framer
(57 octet)
Description
15
0
Not used
14 One Second Count Set if the one-second timer input is detected.
13 Invalid FEBE
Set if an invalid FEBE is detected (9–F).
12 FEBE All-1s
Set if an invalid FEBE = F is detected.
11 PLCP FEBE Error
Set if any valid non-0 FEBE value (values 0x1–0x8) is detected in the G1 octet in 57-octet PLCP
formats
10 PLCP BIP Error
Set if there is an error in the BIP-8 code (B1 octet) checking in 57-octet PLCP formats.
9 PLCP Frame Error Set if there is an error in either the A1 or A2 octets of the PLCP frame pattern for 57-octet PLCP
formats.
8 PLCP Yellow
PLCP yellow indicates that the yellow alarm bit in the G1 octet (57-octet modes) has been active
for 10 consecutive PLCP frames.
7 PLCP LOF 2–3
Set if PLCP LOF is high for three consecutive one-second latching signals (rising edge on
ONESECI).
6 PLCP LOF
Set when PLCP OOF is active for eight consecutive PLCP frames.
5 PLCP OOF
Set if the PLCP OOF state has been entered for 57-octet PLCP formats.
4–1
x
Not used
0 LOS (Input)
Set if there is a LOS detected by the internal B3ZS/HDB3 decoder or if the RXLOS~ input pin is
active low. Internal LOS detection is the occurrence of 175 ± 75 zeros prior to B3ZS/HDB3
decoding. The RXLOS~ input pin should be tied high unless an external line interface unit
provides an active low LOS indication.
NOTE(S): “x” = Bit position is undefined and should be ignored.
3-34
Conexant
100046C