6100 ADCCP Programming Manual

Station States and Transitions
ADCCP Link and Station Management
069225 Tandem Computers Incorporated 2–7
affect station information maintained by Level 2. (See Section 6, “Requests and
Response,” for a description of these requests.)
The state machine or machines maintained by Level 2 can be in one of four states:
Logically disconnected state (LDS)
Mode-setting state
Initialization state (IS)
Information-transfer state (ITS)
These states apply to the local station, not to the remote station with which it is
communicating. Figure 2-4 shows the basic station states and the events that cause
state transitions.
Figure 2-4. Station States and Transitions
Logically
Disconnected
State (LDS)
Mode-setting
State
Line Downloaded
and Started
DISC
Sequence
MODE SET
Request
Disconnect Request
or Modem Failure
Modem Failure
MODE SET
Request
Information
Transfer
State (ITS)
Initialization
State (IS)
Disconnect Request
or Modem Failure
MODE SET
Request
SIM
Sequence
SNRM(E),
SARM(E),
or
SABM(E)
Sequence
010