cx28365 Mindspeed Technologies, cx28365 Datasheet - Page 46

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

Functional Description
Figure 2-9. E3-G.832 System Transmit Timing (TxSYNC Indicates Frame Start)
Figure 2-10. E3-G.832 System Transmit Timing (TxSYNC Indicates Overhead Bits)
2.1.1.3
2-8
TxGCKO(inv)
TxGCKO(inv)
TxGCKO
TxSYNC
TxGCKO
TxSYNC
TxDATI
TxDATI
TxCKI
TxCKI
Low during 8
In
FA1, FA2, EM, TR, MA, NR, and GC bytes) and high during data bit positions
regardless of the Opportunity bit source.
Transmitter Overhead Bit Generation
The framer can use any of the following four techniques to insert framing and
Opportunity bits:
The allocation of the Opportunity bits to one method is done for groups of overheads.
The options vary for each one of the four main modes of operation. The Transmit
Overhead Insertion 1 Control register and Transmit Overhead Insertion 2 Control
register control the allocation. The register setting ability changes according to the
framer mode of operation.
Overhead bits in various modes.
GC (8 bits)
GC (8 bits)
1.
2.
3.
4.
GC bits
Figure
Preliminary Information/Mindspeed Proprietary and Confidential
Internal-Auto—Automatically generated by the internal circuitry, (e.g., automatic
FEBE/REI).
Internal-Reg—Overhead bits are microprocessor-controlled.
External-Data—Overhead bits are supplied with the data stream.
External-Pin—Overhead bits are is input from an external pin (TEXTI) with the
gapped clock (TEXTCKO).
2-10, TxSYNC is low during all Opportunity bit positions (i.e., low during
1888 Payload
Mindspeed Technologies™
1888 Payload
bits
bits
Low during 16 bits
Low during 16 bits
Table 2-1
FA1 + FA2
FA1 + FA2
Low during
16 bits
16 FA1 &
16 bits
FA2 bits
indicates the availability for the various
464 Payload
464 Payload
High during 2408 bits
bits
bits
Low during 8 bits
Low during 8 bits
EM (8 bits)
Low during 8
EM (8 bits)
EM bits
CX28365/6/4 Data Sheet
Payload
Payload
500028C
500028_022
500028_023