cx28250 Mindspeed Technologies, cx28250 Datasheet - Page 53

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

CX28250
ATM Physical Interface (PHY) Devices
2.3.3 Line Overhead
28250-DSH-002-C
The Line Overhead handles the transport of path-level payloads across the
physical medium. This layer of the overhead provides synchronization and
multiplexing functions for the Line layer. These functions include maintenance
and line protection. The Section Overhead must be terminated before the Line
Overhead can be accessed. The transmit and receive functions of the Line
Overhead are described in
Table 2-5. Line Overhead Transmit and Receive Functions
H1/H2
H3
B2
K1/K2
D4-12
S1
Z2
M1
Byte
Mindspeed Technologies
620A/93FF hex pointer
00 hex
Calculated, error insertion
Insertable via register
00 hex or external serial access
Insertable via register
Generated from the contents of
TXZ2
Line REI inserted
Transmit
Table
2-5.
2.3 SONET/SDH Framer and Overhead Processor
™
Full GR.253 pointer processor
Used in pointer processor
Checked, errors counted
Checked, interrupt on change
External serial access
Checked, interrupt on change
Checked, interrupt on change after a 3
frame integration
Checked, errors counted
2.0 Functional Description
Receive
2-17