cx28250 Mindspeed Technologies, cx28250 Datasheet - Page 62

• Manufacturer Part Number: cx28250
• Description: Cx28250 Atm Physical Interface Phy Devices
• Manufacturer: Mindspeed Technologies

2.0 Functional Description
2.3 SONET/SDH Framer and Overhead Processor
2-26
2.3.4.4 G1
The Path Status byte, G1, is used to convey path terminating status and
performance monitoring information back to an originating STS PTE. This
feature permits the status and performance of the complete duplex path to be
monitored at either end, at any point along that path. Bits 1–4 contain the Remote
Error Indication (REI) count, which is the number of errors indicated by the B3
byte. The REI bits have nine valid values (0000–1000). A value greater than 8 is
counted as having no errors. Bits 5–7 are a path RDI (yellow alarm) indication.
transmitter automatically generates RDI-P indications in these three bits if the
AutoPthRDI control (bit 1 in TXPTH 0x0E) is set to a 1.
values that are transmitted for various receiver alarm conditions. The user can
override these values by setting AutoPthRDI to 0 and directly writing the desired
value to be transmitted into TXPTH bits 3–1.
Table 2-10. Transmitted RDI-P Values
When 10 consecutive frames of the same value are received, the value is latched
into RXG1 (0x19) so that it can be read. An interrupt is generated if the new value
represents an alarm condition change. Interrupts are generated when entering and
exiting alarm conditions. The EnhanceRDI control bit (ENPTH 0x37 bit 0)
determines whether only bit 5 is observed (set to 0 to interwork with old
equipment) or bits 5–7 are observed (set to 1 to conform to new equipment
standards).
Table 2-11. Receiver RDI-P Interpretation (For the CX28250-23)
AIS-P, LOP-P, LOS, LOF, AIS-L
Bits 5–7 in the G1 byte are used for Path RDI (RDI-P) indications. The
The receiver observes the incoming G1 byte to monitor for RDI-P alarms.
Incoming RDI-P
G1 bits 5-7
Receiver Defect
000
001
010
011
100
101
110
111
Mindspeed Technologies
UNEQ-P
PLM-P
Table 2-11
None
summarizes the receiver RDI-P interpretation.
No remote defect
No remote defect
No remote defect
No remote defect
EnhanceRDI=0
Interpretation
Remote defect
Remote defect
Remote defect
Remote defect
Transmitter G1 (bits 5-7)
™
ATM Physical Interface (PHY) Devices
000
010
101
110
Remote connectivity defect
Remote payload defect
Remote server defect
Table 2-10
No remote defect
No remote defect
No remote defect
No remote defect
No remote defect
EnhanceRDI=1
Interpretation
28250-DSH-002-C
lists the
CX28250