511 -14 1 in 8 -14, Application -14, Figure 1-9 – ADTRAN T1-FT1 User Manual
Page 30: Application

Chapter 1. Introduction
1-14
TSU User Manual
61200060L1-1
511
The 511 pattern is generated and checked by the Nx56k/64k
serial interface. It only appears in the DS0s assigned to the
Nx56k/64k port. When used in conjunction with the payload
loopback at the far end as previously described, an end to
end integrity check can be made on the DTE ports.
1 in 8
The 1:8 pattern is used similarly to the 3:24. Each channel of
the T1 has only one bit set.
Application
Using the V.35 DTE interface, a bridge or router can be
interfaced to the network. The bandwidth used is
programmable at Nx56 or Nx64 data rates for T1 or FT1
service. The bandwidth can be selected as contiguous or
alternate. See Figure 1-9.
Figure 1-9. Simple Bridge Application on a T1 or FT1 Circuit
TSU TSU
NX56/64
V.35
NX56/64
V.35
(Public T1)
Bridge Router
Bridge Router