Gestetner A193 Service Manual page 772

D-Channel Layer 1 Dump List
How to Read the Dump List
1.2.3. Layer 1 Status
The ITU-T I.430 recommendation (the basic user-network interface - Layer 1
specification) specifies layer 1 activation/deactivation procedures.
Before understanding the procedures, the status and INFO signals should be
noted.
TE (Terminal Equipment) Status
Status
TE is turned off.
F1
F2 TE is turned on, but no signal is exchanged.
F3 TE is stopped. No signal is exchanged between TE and NT.
F4 TE is waiting for the response to INFO1 signal from NT.
F5 TE is checking if the signal from the NT is INFO2 or INFO4.
TE is waiting for signals from NT after receiving INFO2 signal.
F6
F7 TE and NT are in synchronized condition.
TE has failed to synchronize to NT, and waiting for the stop request from
F8
NT
NT (Network Termination) Status
Status
NT is stopped.
G1
G2 NT is sending INFO2 signal.
G3 TE and NT are in synchronized condition.
G4 NT is terminating itself.
INFO Signals
NT to TE Direction
No signal
INFO0
(11111111...)
Activation signal in
INFO2 synchronized condition
(B=0, D=0, E=0, A=0)
Synchronized frame
INFO4
SM
Description
Description
TE to NT direction
No signal
INFO0
(11111111...)
Activation signal in
INFO1 non-synchronized condition
(+0-0111111+0-0)
Synchronized frame
INFO3
A-7 APPENDIX A