Rainbow Electronics DS3170 - Manual (Page 110)

DS3170 DS3/E3 Single-Chip Transceiver
110 of 233
then checking the next 32 data stream bits. Synchronization is achieved if all 32 bits match the incoming pattern. If
at least six incoming bits in the current 64-bit window do not match the receive pattern generator, automatic pattern
resynchronization is initiated. Automatic pattern resynchronization can be disabled.
Refer to Figure 9-28 for the PRBS synchronization diagram.
Figure 9-28. PRBS Synchronization State Diagram
Sync
Load Verify
1 bit error
32 bits loaded
32
b
its
w
ith
ou
t e
rr
or
s
6 o
f 6
4 b
its
w
ith
er
ro
rs
9.11.4.2 Receive Repetitive Pattern Synchronization
Repetitive pattern synchronization synchronizes the receive pattern generator to the incoming repetitive pattern.
The receive pattern generator is synchronized by searching each incoming data stream bit position for the
repetitive pattern, and then checking the next 32 data stream bits. Synchronization is achieved if all 32 bits match
the incoming pattern. If at least six incoming bits in the current 64-bit window do not match the receive PRBS
pattern generator, automatic pattern resynchronization is initiated. Automatic pattern resynchronization can be
disabled.
Refer to Figure 9-29 for the repetitive pattern synchronization state diagram.