What Is An Event - HP 81200 User Manual

Introduction to the System Event Handling Principles

What is an Event?

A pure data generating system equipped with the HP E4831A clock module
has only limited capabilities. The only event it can recognize is a status
change at its EXT INPUT connector.
An HP 81200 system equipped with the HP E4805A clock module has a
whole bunch of options. It can react on
• any bit combination of the 8-bit trigger pod (see "Trigger Pod" on
page 22),
• any bitstream error detected by one of the analyzer modules,
• the VXI ECL trigger lines T0 and T1,
• an event trigger command issued locally or remotely.
All combinations are allowed. Events can be generated within the
HP 81200 system or by external sources. Theoretically, the system can
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differentiate between 2 events.
In practice, 10 events can be defined—five for immediate actions and five
for deferred actions.
Events Causing Deferred Action
Actions on such events occur at the end of the current data block. If the
events come unsynchronized, this feature ensures that the current block is
properly executed and terminated.
These events are associated with priorities. Event number 5 has the
highest priority, event number 1 the lowest.
N O T E Events for immediate action override events for deferred action.
Events Causing Immediate Action
Actions on such events occur immediately (although there is an internal
delay). They can be used to set a trigger or to abort the test, for example.
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HP 81200 Data Generator/Analyzer Platform User Guide, Revision 2.1