tfra08c13 ETC-unknow, tfra08c13 Datasheet - Page 42

• Manufacturer Part Number: tfra08c13
• Description: Tfra08c13 Octal T1/e1 Framer
• Manufacturer: ETC-unknow

TFRA08C13 OCTAL T1/E1 Framer
Frame Formats
T1 Frame Recovery Alignment Algorithms
When in a loss of frame alignment state, the receive framer searches for a new frame alignment and forces its inter-
nal circuitry to this new alignment. The receive framer’s synchronization circuit inhibits realignment in T1 framing
formats when repetitive data patterns emulate the T1 frame alignment patterns. T1 frame synchronization will not
occur until all frame sequence emulating patterns disappear and only one valid pattern exists. The loss of frame
alignment state will always force a loss of superframe alignment state. Superframe alignment is established only
after frame alignment has been determined in the D4 and SLC -96 frame format. Table 15 gives the requirements
for establishing T1 frame and superframe alignment.
Table 15. T1 Frame Alignment Procedures
42
D4: Frame
D4: Superframe
SLC -96: Frame
SLC -96:
Superframe
DDS: Frame
ESF
Frame Format
Using the F
secutive F
error-free. Once frame alignment is established, then superframe alignment is determined.
After frame alignment is determined, two valid superframe bit sequences using the
F
Using the F
secutive F
established, then superframe alignment is determined.
After frame alignment is determined, superframe alignment is established on the first valid
superframe bit sequence 000111000111.
Using the F
consecutive F
DDS format, there is no search for a superframe structure.
Frame and superframe alignment is established simultaneously using the F
Alignment is established when 24 consecutive F
superframe alignment is established, the CRC-6 receive monitor is enabled.
S
(continued)
bits must be received error-free to establish superframe alignment.
T
T
T
T
T
and F
frame bits (48 total frames) are received error-free. Once frame alignment is
frame position as the starting point, frame alignment is established when 24 con-
frame position as the starting point, frame alignment is established when 24 con-
frame position as the starting point, frame alignment is established when six
T
/F
S
S
frame bits and the DDS FAS in time slot 24 are received error-free. In the
frame bits, excluding the twelfth F
Alignment Procedure
E
bits are received error-free. Once frame/
S
bit, (48 total frames) are received
Preliminary Data Sheet
Lucent Technologies Inc.
Lucent Technologies Inc.
E
October 2000
framing bit.