mt9072av2 Zarlink Semiconductor, mt9072av2 Datasheet - Page 53

• Manufacturer Part Number: mt9072av2
• Description: Octal T1/e1/j1 Framer
• Manufacturer: Zarlink Semiconductor

achieve CRC-4 multiframe alignment by the end of a predefined period, the distant end is considered to be a
non-CRC-4 interface. When the distant end is a non-CRC-4 interface, the near end automatically suspends receive
CRC-4 functions, continues to transmit CRC-4 data to the distant end with its E-bits set to zero, and provides a
status indication. Naturally, if the distant end initially achieves CRC-4 synchronization, CRC-4 processing will be
carried out by both ends. This feature is selected when control bit AUTC (control register address Y00) is set to
zero.
5.2.4.1
1. The basic frame alignment, signaling multiframe alignment, and CRC-4 multiframe alignment functions operate
2. The receive channel associated signaling bits and signaling multiframe alignment bit will be frozen when multi-
3. Manual re-framing of the receive basic frame alignment and signaling multiframe alignment functions can be
4. The transmit RAI bit will be one until basic frame alignment is established, then it will be zero.
5. E-bits can be optionally set to zero until the equipment interworking relationship is established. When this has
6. All manual re-frames and new basic frame alignment searches start after the current frame alignment signal
7. After basic frame alignment has been achieved, loss of frame alignment will occur any time three consecutive
8. When CRC-4 multiframe alignment has been achieved, the primary basic frame alignment and resulting multi-
in parallel and are independent.
frame alignment is lost.
performed at any time.
been determined one of the following will take place:
position.
incorrect basic frame alignment signals are received. Loss of basic frame alignment will reset the complete
framing algorithm.
frame alignment will be adjusted to the basic frame alignment determined during CRC-4 synchronization. There-
fore, the primary basic frame alignment will not be updated during the CRC-4 multiframe alignment search, but
will be updated when the CRC-4 multiframe alignment search is complete.
a) CRC-to-non-CRC operation - E-bits = 0,
b) CRC-to-CRC operation - E-bits as per G.704 and I.431.
Notes for Synchronization State Diagram (Figure 7)
Zarlink Semiconductor Inc.
MT9072
53
Data Sheet