cx28365 Mindspeed Technologies, cx28365 Datasheet - Page 56

• Manufacturer Part Number: cx28365
• Description: X12, X6, X4 T3/e3 Framer And Atm Cell Transmission Convergence Sublayer Processor
• Manufacturer: Mindspeed Technologies

Functional Description
2-18
E3-G.832 Mode
In E3-G.832 mode, three alarms are generated: Remote Defect Indicator (RDI),
Remote Error Indicator (REI), and Alarm Indication Signal (AIS).
RDI
Bit 1 of MA field at E3-G.832 34.368 Mbps frame structure is used to transmit RDI.
Transmission of RDI in E3-G.832 mode is similar to RAI in E3-G.751 mode. Each
framer has an option to insert the RDI bit:
If automatic RDI is enabled (by setting bit AutoRAI in Transmit Overhead Insertion 1
Control register to 1), as long as LOS or OOF conditions are detected at the receiver,
the transmitter automatically inserts 1 at the transmitted RDI bit. When LOS and OOF
conditions are no longer detected, the transmitter sets the transmitted RDI bit to 0 (no
RDI alarm). In the automatic RDI mode, the transmitter side sends automatic RDI as
long as OOFAlm or LOSAlm bits at the Maintenance Status register are set.
Forcing a RDI alarm can also be done by setting TxAlm[1] to 1. As long as TxAlm[1]
is set to 1, RDI bit contains 1, regardless of other RDI bit source settings.
REI
REI is transmitted in bit 2 of the MA octet at the E3-G.832 34.386 Kb frame structure.
For each framer this bit can be either externally supplied (with the data stream or from
an external pin) or internally generated automatically.
If the REI bit is selected to be generated internally, the transmitter sets this bit to 1
(generate REI signal) if one or more errors are detected by BIP-8 code received in the
EM field. The REI bit is otherwise transmitted as 0 (no BIP-8 errors). During receiver
LOS or AIS, automatic REI remains active. During receiver OOF condition, REI is
transmitted as 0 in this mode.
AIS
The ability to transmit an all-1s AIS code is also supplied for the E3-G.832 mode
(similar to the E3-G.751 mode).
In E3-G.832 mode, transmission of AIS (unframed all 1s) is enabled by setting
TxAlm0 high. When AIS is enabled, the framer ignores the inserted data and
Overhead bit settings and transmits an all 1s code, as long as TxAlm0 bit is set to 1.
Start of AIS transmission and termination in E3-G.832 is immediate with the setting
of TxAlm0.
NOTE:
Preliminary Information/Mindspeed Proprietary and Confidential
With payload (when the method of overhead insertion is all with data)
From TEXTI pin
Automatically generate it
Force RDI alarm sending by a control register
Mindspeed Technologies™
Automatic RDI transmission does not react to TR mismatch because the framer does
not check TR mismatches. When the method of overhead insertion is all with data,
setting AutoRAI or ExtRAI has no influence on the transmitted RDI-bit.
CX28365/6/4 Data Sheet
500028C