User's Manual

HARSFEN0602
(AOK) indication, or brakes output.
The association of output pins to functions is described in detail in the Command Reference
Manual, the OL[] command.
13.4 Events, and response methods
The Harmonica identifies the following events
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:
Change of a GPI (General Purpose digital Input)
Change of a limit switch
Change of a "Home" switch
Change of an "Enable" switch
Change of a "Stop" switch
Change of a "Begin" switch
Encoder Index pulse.
In order to identify an event, the event needs to be defined. From the above list, only the Index is
defined permanently. All the other events are programmable. The Harmonica has 6 digital input
connector pins. The connector pins can be routed, with direct or inverted polarity, to functions
like general-purpose digital input or RLS. To learn how to route connector pins to functions,
refer the IL[] command in the Command Reference Manual.
Events can be handled in three speed levels.
Manual inquiry
Periodical inquiry
Automatic routines
Real time (Motion management, Homing, Capture, and Flag)
13.4.1 Manual inquiry
The manual inquiry is the simplest method. By using the IP/IB[] commands, one can inquire the
state of the input pins. The user program logics, or a host, can consider the inquiry results.
The table below summarizes some of the properties off manual inquiry.
Topic Comment
Capture probability: Low. Even if a digital input is continuously polled (with great
communication or user program loading), an input pulse may
slip away unnoticed between consecutive polls.
Deterministic delay: No. Depends in the non-deterministic delays of the interpreter
or the user program management.
Use: Non time-critical inquiries.
Simple operations.
13.4.2 Periodical Inquiry
The periodical inquiry is possible only in CAN networks. The user can map the digital input
word to a synchronous PDO. The host can collect the inputs state of many slaves as a response
to single Sync.
The table below summarizes some of the properties off periodical inquiry.
Topic Comment
Capture probability: Low. An input pulse may slip away unnoticed between
consecutive Syncs.
Deterministic delay: Yes, 0.5msec maximum + CAN network time.
Use: CAN networks only.
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The Harmonica also identifies emergency events such as over-voltage, short-circuit, or over-current. The emergency
events are treated in the chapter on "Limits, Protections, Faults, and Diagnosis"