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N:\mkt\MANUALS\HP8924C\APPMOD\BOOK\chapters\amcproc.fb
Chapter 9, 264 Using the Analog Call Processing Subsystem
Using Remote (HP-IB) Control
Register
state and then determine when to read the mobile station’s registration
information in order to make a determination as to whether the mobile station
registered correctly.
In the manual user interface, the annunciators supply this state information to the
operator. In the remote user interface, the Call Processing Status Register Group
supplies the state information to the control program.
The control program can access this information in one of two ways; by
polling
the status registers or by using the
service request
feature of the HP-IB. If properly
implemented, either method can be used to obtain the information. Refer to Status
Reporting chapter of the HP 8924C User’s Guide.
When To Query Data Messages Received From The Mobile Station
The Analog Call Processing Subsystem makes available to the control program
many data messages received from the mobile station. For example - if the
simulated Base Station sends a registration message to the mobile station, the
registration information (MIN, ESN, SCM) received from the mobile station can
be read by the control program.
The data messages are displayed on the CRT after the successful completion of
the call processing function (registration, page, origination, etc.). When call
processing functions complete, state changes occur within the Analog Call
Processing Subsystem. For example - when a registration completes the Analog
Call Processing Subsystem exits the register state (the
Register
annunciator is
turned off) and returns to the active state (the
Active
annunciator is turned on).
The control program should only query the Test Set for the data messages after all
the state transitions are complete. For example - the control program should not
attempt to read the MIN, ESN or SCM until after the
Register
annunciator is
turned off and the
Active
annunciator is turned on.
This is because the Test Set has a multi-tasking architecture wherein multiple
processes execute on a priority driven and an event driven basis. Each process is
given a timeslice on the CPU depending upon its priority, the priority of other
processes and the nature of the events occurring within the Test Set.
Upon completion, processes within the Analog Call Processing Subsystem pass
data messages received from the mobile station to the Measurement Display
Process which displays the information on the CRT during its next CPU timeslice.
If the control program attempts to query the data fields before the Measurement
Display Process has posted the information to the CRT, it is possible that the
fields will be blank or contain data from a previous call processing function.