Elmo HARmonica, HARSFEN0602 174, Events, and response methods, Manual inquiry, Periodical Inquiry

HARSFEN0602ElmoHARmonicaSoftwareManual PRELIMINARYDRAFT

(AOK) indication, or brakes output.

The association output pins to functions is described in detail in the Command Reference Manual, the OL[] command.

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13.4 Events, and response methods

The Harmonica identifies the following events6:

Change 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)

13.4.1Manual 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.

13.4.2Periodical 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.

6The 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"